Workers' compensation - Competing expert evidence - Causation - Burdens - Disentangling competing causes - Credibility - Discretion to refuse compensation

Workers' Compensation and Injury Management Act 1981 (WA) (repealed)

Workers Compensation and Injury Management Act 2023 (WA)

Anderson v Mineral By-Products Pty Ltd (1987) 8 WCR (WA) 37

BHP Billiton Iron Ore Pty Ltd v Treby [2017] WADC 6

Cole v P & O Ports Ltd [2002] WASCA 157

D'Orsogna Ltd v Zhang [2019] WADC 73

Education Department of Western Australia v Morgan [2000] WASCA 291

Kooragang Cement Pty Ltd v Bates (1994) 35 NSWLR 452

Leggett v Argyle Diamond Mines Pty Ltd [2000] WASCA 182

Lockwood-Hall v BHP Billiton Nickel West Pty Ltd (Unreported, WACC, C5-2012, 18 May 2012)

Massih v Electricity Networks Corporation t/as Western Power [2016] WADC 146

Minister for Education v Shire of Northam [2016] WADC 42

Minister for Immigration and Citizenship v Li [2013] HCA 18; (2013) 249 CLR 332

Minister for Immigration and Citizenship v SZMDS [2010] HCA 16; (2010) 240 CLR 611

Napier v BHP Billiton (Worsley Alumina) Pty Ltd [2015] WASCA 230; (2015) 49 WAR 243

Purkess v Crittenden [1965] HCA 34; (1965) 114 CLR 164

R v Hill [2012] ACTSC 121

Re Iliadis v Comcare (1996) 41 ALD 576

Re Schofield v Comcare [1995] AATA 42; (1995) 38 ALD 124

Smart v Power [2019] WASCA 106

Treasure v WA Country Health Service (Unreported, WACC, C17-2010, 26 November 2010)

Ward v Corrimal-Balgownie Collieries Ltd [1938] HCA 70; (1938) 61 CLR 120

Watts v Rake [1960] HCA 58; (1960) 108 CLR 158

Wilson v Bentley Health Service (Unreported, WACC, C31-2007, 6 July 2007)

1. Mr Smith is a field technician. He worked on offshore oil rigs. In 2020 his employer Frank Oilfield Services deployed Mr Smith's labour for onshore work in one of their workshops. On 22 May 2020 Mr Smith lifted a pallet (the pallet incident) and as he did so, he injured his lower back and sustained a left-sided inguinal hernia.
2. A workers' compensation claim was accepted by Frank Oilfield Services.
3. While on weekly payments of compensation, Mr Smith injured his right knee in a swimming pool. Mr Smith says the right knee injury occurred because of the lower back injury. Frank Oilfield says it did not.
4. Mr Smith's prescribed sum was exhausted in June 2022. Mr Smith claims that the injuries he sustained when lifting the pallet include the consequential right knee injury, and that those injuries have left him totally incapacitated for work, his social and financial circumstances and needs justifying an extension of the prescribed amount.
5. On 23 February 2024 Arbitrator Yates dismissed Mr Smith's application for that extension of the prescribed amount. In summary, the arbitrator found that Mr Smith's compensable injury has resolved.
6. Mr Smith says he erred in so finding.

1. A consideration of the merits of the appeal requires, self-evidently, addressing the grounds themselves. Before I do that, however, I have set out in summary the arbitrator's reasons for decision, including his findings on the credibility of the appellant, and some findings he made which are common to all the grounds of appeal.
2. However, a practical matter arose at the hearing of the appeal which can be addressed briefly. The arbitrator's reasons are dated 23 February 2024. At that time, the Workers' Compensation and Injury Management Act 1981 (WA) (repealed) (the former Act) was in place. That Act was repealed and replaced by the Workers Compensation and Injury Management Act 2023 (WA) (the 2023 Act), coming into operation on 1 July 2024. While the arbitrator's decision came before the commencement of the 2023 Act, this appeal was heard on 5 September 2024.
3. Both parties agreed, rightly in my view, that the consequence of provisions in the 2023 Act is that the appeal must proceed under the 2023 Act. Further, both parties agreed, as do I, that at this stage, the questions raised as to leave, and any tests as to causation or other questions of law relevant to this appeal, are not altered by the 2023 Act.
4. Both parties also agreed that as the arbitrator applied the relevant sections from the former Act in determining the matter, consideration of the law as he applied it should be referenced to the sections of the former Act.
5. There is a more difficult question about what occurs if I uphold the appeal, particularly in relation to the application of s 79 of the former Act, which does not have a replacement in the 2023 Act. Given the outcome of this appeal, I do not have to determine that issue.

1. The arbitrator structured his decision into the resolution of issues. He identified those issues as:[1]

(a) What injury did Mr Smith sustain in the pallet incident, the compensable occurrence of 22 May 2020?

(b) Did Mr Smith sustain a compensable condition to his right knee in a swimming pool in December 2020?

(c) Does Mr Smith have a current injury that is compensable under the Act?

(d) Has any current compensable injury resulted in the permanent total incapacity for work?

(e) Should an order as to the total liability of the respondent be made having regard to the social and financial circumstances and the reasonable financial needs of Mr Smith?

(f) If an order as to the total liability of the respondent is made, in what amount, at what rate, and commencing when?

(g) Should the respondent pay Mr Smith's outstanding medical expenses for the lower back?

(h) Should the respondent pay Mr Smith's outstanding medical expenses for the right knee?

(i) Should compensation be refused on the basis that at the time of seeking employment Mr Smith wilfully and falsely represented himself as not having previously suffered the injury?

1. Before he considered the issues, the arbitrator addressed the appellant's credibility.[2]
2. He found that the medical history given by the appellant to some of the medical professionals was inconsistent and unreliable. Accordingly, he found that the weight that could be attached to those expert medical opinions in relation to the cause of the symptoms leading to the incapacity was affected, and in the case of one professional, Dr Jenkins, leading him to reject Dr Jenkins' opinions and conclusions as to the cause of the current incapacity.
3. As much of the arbitrator's findings rely on his findings on the appellant's credibility, the rejection of Dr Jenkins' opinion and the acceptance of other medical opinions, I will set out his findings on credibility, his general findings of fact and the medical evidence and the arbitrator's findings.

1. The arbitrator found that the appellant did not give truthful, accurate and reliable evidence at the arbitration hearing. He determined that Mr Smith's diminished credibility diminished the reliance that could be placed on his evidence, relying on it only where it was corroborated by other evidence.
2. However, he did find that the appellant was not a malingerer, and had current ongoing genuine symptoms affecting his capacity to work 'to some degree' requiring ongoing medical treatment.[3]
3. The arbitrator's findings on credibility and reliability were based on the manner in which the appellant gave his oral evidence, on the histories given to the medical practitioners as recorded by the medical practitioners and answers he provided on forms. I will address his findings in those respects in more detail when I set out the arbitrator's findings.

1. In considering the appellant's credibility, the medical evidence and the issues, the arbitrator made findings of fact:
   1. The appellant had previously suffered two medical conditions in connection with his previous employment, being at least an injury to his right knee on 17 July 2017 when dragging a bag of oysters, requiring surgery,[4] and an injury to the lower back on 12 January 2018 when lifting bags of oysters.[5] Thus, those injuries were caused in two separate incidents.[6]
   2. Even if both injuries were caused in the same incident, the appellant was obtaining medical advice and treatment in New Zealand in 2018 for a lower back complaint connected with his employment.[7]
   3. The appellant received compensation in New Zealand for each of those injuries.[8]
   4. The appellant had had significant or recurrent problems with right knee pain arising from a rugby injury in 1999[9] and right knee pain reported to doctors in 2017 and 2018 from the July 2017 injury.[10]
   5. The appellant had had significant or recurrent problems, and investigation, with lower back pain.[11] This pain was reported to doctors in 2018 and 2019, including the reporting of long-standing low back pain to his general practitioner Dr Selvendra (Park Medical Group) on 24 April 2019 and 13 May 2019,[12] and from at least 21 February 2018 (Dr Sanderson) and as late as 3 December 2019 (Dr Yong) (Park Medical Group).[13]
   6. The appellant was referred to a neurosurgeon by Dr Selvendra for his ongoing lower back condition in May 2019,[14] and by Dr Yong for his lower back condition in December 2019.[15]
   7. The appellant completed a pre-employment medical form on 19 June 2019,[16] and at that time:

(a) the appellant had a current illness being a back injury when he applied for employment with the respondent, as consistently reported to doctors;[17]

(b) that history involved more than 'little niggles';[18] and

(c) the appellant's lower back was not healthy before the compensable injury.[19]

1. Post the compensable pallet incident, the appellant either did not tell of, or downplayed to, medical practitioners, his pre-dating lower back medical history:

(a) he did not tell occupational physician Dr Tan, who provided certificates as to incapacity from 2 July 2020 to 11 January 2021;[20]

(b) he did not tell reporting occupational physician Dr Dayoub when reviewed in February and October 2021;[21]

(c) he told Dr Dayoub that he had had 'little niggles' in his back in the past in December 2022;[22] and

(d) he did not tell approved medical specialist Dr Jenkins[23] nor orthopaedic surgeon Dr Phillips[24] when reviewed.

1. Dr Dayoub is an occupational physician who provided reports to the respondent. He provided four reports and was not required for cross-examination at the arbitration hearing.
2. The appellant underwent an MRI lumbosacral spine in February 2021, the report of the results of which became Exhibit 14 at the arbitration hearing. On 4 March 2021 Dr Dayoub reported on those results and provided a general report of the appellant's medical conditions, that report becoming Exhibit 15 at the arbitration hearing.
3. The report included a history as reported to him by the appellant, however Dr Dayoub said that history in relation to the injury was 'vague and sketchy'. Despite being vague and sketchy, Dr Dayoub appears to have believed that he had sufficient information to summarise the mechanism of the appellant's lifting of the pallet, the weight of the pallet and the immediate onset of symptoms in particular areas. Dr Dayoub noted that the appellant used a below elbow crutch on his right side for a right knee injury when he saw him and noted a mild antalgic gait, and other consequences of the knee injury. He reported his findings in relation to the physical nature of the appellant's presentation and summarised the findings of an ultrasound performed on 3 July 2020 and the MRI lumbosacral spine.
4. He considered that the present lower back symptoms were contributed to by a symptomatic degenerative disease of the lumbosacral spine.
5. Dr Dayoub said he had insufficient information to accurately relate the then symptoms and condition to the workplace injury. General practitioner records were called for.
6. Dr Dayoub furnished a second report on 25 October 2021, which became Exhibit 17 at the arbitration hearing. The called for records had not been received. Again, however, an antalgic gait was noted and Dr Dayoub outlined his clinical findings on examination. He maintained his inability to accurately determine the liability for the lower back pain based on insufficient information.
7. A third report issued on 14 December 2022 became Exhibit 20 at the arbitration hearing. By this time, reports had been received and considered by Dr Dayoub, according to the schedule of documents at pages 11 and 12 of his report. Specifically, Dr Dayoub had considered:
   • Radiology reports regarding the left groin and the MRI of the lumbosacral spine
   • Pain medicine specialist reports
   • General surgeon report in relation to the hernia
   • GPs: Dr Kumar '25 May 2020, Clinical Notes, 4 Sep 2020', Sonic Health Plus 2021
   • Physiotherapy reports from August 2020 to September 2021
   • Rehabilitation reports from July 2021 and April 2022
   • Work certificates from 2020 to October 2022.
8. While not specifically mentioned in that list, but referenced in the body of his report, Dr Dayoub considered a 'health summary from Park Medical Group. This was printed on 20 October 2022'. In his report, he has specifically referred to:
   1. A surgery consultation recorded by Dr Selvendra, general practitioner dated 4 April 2019, saying '[i]t was suggested that he had lower back pain for one year. He was diagnosed with pinched nerve in New Zealand. He was taking sleeping tablets and non-steroidal anti-inflammatory medications. Dr Selvendra discussed scans and ongoing medications'.
   2. A surgery consultation completed by Dr Selvendra dated 16 April 2019, saying 'It appears that he had a CT scan of the lumbosacral spine' and noting the outcome as he had previously reported.
   3. A surgical consultation dated 13 May 2019, saying 'It was suggested that he has lower back pain. He has had facet joint injections and he was advised to have surgery, lumbar spine fusion, in New Zealand; however, he moved to Perth to be with his daughter. He was recommended to see a neurosurgeon'.
   4. A surgical consultation recorded by Dr Yong, general practitioner dated 3 December 2019, saying 'It was recommended that he had long-standing back pain and awaiting neurosurgeon public review. It was suggested that he was using tramadol and codeine which did not help'.
9. Having referred to those consultations, Dr Dayoub's findings were:

Mr Smith has a pre-existing history of chronic lower back pain. I find the history that was provided by Mr Smith to be inconsistent with the clinical records that was provided to me.

Mr Smith said that he had little niggles of his lower back in the past, but he never required medical or allied health treatment; however, the clinical records suggest that he had chronic lower back pain for many years prior to the workplace incident of 2[2] May 2020, for which he required cortisone injections, and he was recommended to see a neurosurgeon.

The workplace incident that occurred on 2[2] May 2020 may have caused a temporary aggravation of the pre-existing lower back pain; however, I consider such aggravation to have ceased by now. I believe that his ongoing back symptoms are secondary to the non-work-related injury of his right knee which occurred on 12 December 2020. I believe that his altered gait as a result of the right knee injury has caused an aggravation of his chronic lower back pain.

1. The arbitrator replicated these findings at [95] and [96].
2. In relation to Dr Dayoub's reports, the arbitrator also found, in summary:

(a) as of 4 March 2021 Dr Dayoub had not been provided with any medical records that pre-dated the pallet incident;[25]

(b) given the history revealed by the medical records pre-dating the pallet incident, the history given by the appellant to Dr Dayoub prior to the 4 March 2021 report, being a denial of 'any past history of similar symptoms in the past', was not true;[26]

(c) in that first report Dr Dayoub acknowledged the lack of information and therefore inability to accurately determine whether the degenerative disease had been rendered symptomatic as a result of the workplace incident of May 2020 and recommended gaining access to clinical general practitioner records to accurately do so;[27]

(d) by the time of the third review appointment on 7 December 2022 Dr Dayoub received at least some of the past medical records that were in evidence before the arbitrator, and as a result made the findings I have set out above; and

(e) a fourth report dated 21 December 2022 which became Exhibit 22 at the arbitration hearing commissioned to comment on a labour market research report contains Dr Dayoub's opinion that the ongoing incapacity for work is not related to the compensable injury occurring on 22 May 2020, but rather non-work related long-standing history of lower back pain and osteoarthritis of the right knee.[28]

1. In conclusion, the arbitrator found that Dr Dayoub's opinions as to diagnosis of the 'lower back' and causation were compelling. This was because, he said, the reports all set out clearly what information he was relying on to form his opinions, whether that be the appellant's history provided to the doctor or other documentation. He concurred with Dr Dayoub that in the case where the appellant's account of his medical history conflicted with the contemporaneous medical records, the contemporaneous medical records were to be preferred.[29]

1. Dr Phillips is a consultant orthopaedic surgeon who provided a report to the respondent. His report dated 30 June 2023 became Exhibit 31 at the arbitration hearing. He was not required for cross-examination.
2. He was also provided with medical records which pre-dated and post-dated the pallet incident, specifically as noted by the arbitrator, being the Park Medical Group medical records,[30] 'which is the clinic Dr Selvendra and Dr [Yong practice] from'.
3. As the arbitrator noted,[31] Dr Phillips reported to the respondent that he specifically asked the appellant about any prior low back complaint and that the appellant stated that there was 'nil of significance and that he had not ha[d] his lower back investigated prior to this injury'. Dr Phillips continued, 'I note a very comprehensive and complex history which you have documented of complaints in New Zealand in relation to his low back. ... This is inconsistent with his statement which I asked him to confirm that there was no significant prior low-back problem and it had never been investigated'.
4. While not referred to by the arbitrator, it is also notable that Dr Phillips, at pages 5 - 6 of his report, listed: a diagnosis in January 2018 of low back injury and recognised degenerative disc disease; further imaging on 21 February 2019 confirming osteoarthritic changes in the lumbar spine and reports in 2018 of ongoing low back pain; an MRI scan on 13 April 2018 of the lumbar spine identifying an L5 spondylitis but no spondylolisthesis; and also in May 2018 an X-ray of the cervical spine. These led to his conclusion that there was an inconsistency with the appellant's confirmation that there was no significant prior low back problem and that it had never been investigated.
5. The arbitrator found Dr Phillips' report comprehensively detailed the history of the appellant's presentation to doctors after the pallet incident and the investigations undertaken in that period.[32] He accepted Dr Phillips' diagnosis of pre-existing degenerative change in the lower back as Dr Phillips had adequately explained the reasons for his opinion and, given that he found that the appellant's subjective complaint to Dr Phillips of current low back pain was genuine, he accepted Dr Phillips' explanation that the pre-existing (that is, the pre-pallet incident) pathology objectively explained the current subjective complaints.[33]
6. In making that finding, the arbitrator had access to Dr Phillips' report. It can be inferred that the arbitrator's reference to the comprehensive detail of the history and investigations undertaken and adequate explanation of the reasons for his opinion come in part from the answers Dr Phillips gave to the set of questions provided to him by the respondent.
7. In those responses, Dr Phillips, in summary, found:
   1. From the MRI lumbosacral spine his view was that there were long-standing degenerative changes to the spine with no evidence of an acute injury or injury pathology.
   2. The imaging would be consistent with prior reports of imaging undertaken for what appears to have been a significant complaint in 2018/2019.
   3. Consequently, his total agreement with Dr Dayoub's opinion that the pre-existing pathology would explain complaints of pain although he suspected a degree of exaggeration.
   4. There was therefore no ongoing injury, and therefore there could only be current symptoms which relate to multilevel degenerative change.
8. At question 2.10(c) Dr Phillips is asked whether the current lower back symptoms or injuries are caused by a work incident in May 2020. While not specifically directed to the possibility of an ongoing exacerbation of the pre-existing symptoms or condition, or a hastening of the disease, by the pallet incident, in my view the question is broad enough that Dr Phillips, with the background he had been given, would have identified if, while it was not the cause of the current condition, an exacerbation of the current condition was. He has not done so.

1. Dr Jenkins is a medicolegal consultant. He provided one report to the appellant which became Exhibit 1 at the arbitration hearing. He was not required to attend the arbitration hearing to speak to his report or for cross-examination.
2. The oral background provided to Dr Jenkins, as reported by him, was, relevantly:

Mr Smith was reportedly entirely fit and well before an injury at work on 22/05/2022.

Mr Smith denied any lower back or abdominal symptoms immediately prior to 22/05/2020.

Approximately 2018-Low back pain with cortisone injection, recovered.

1. The arbitrator found this to be 'wrong', the appellant having failed to disclose to Dr Jenkins the 'significant history of lower back pain', and that the reference to the 2018 '[l]ow back pain with cortisone injection, recovered' did not represent the true picture, considering all the scans and treatment and reporting of lower back pain to doctors in New Zealand and Australia'.[34] He found that Dr Jenkins proceeded on the wrong basis that Mr Smith was entirely fit and well before 22 May 2020.[35]
2. In relation to the mechanism of the right knee injury, Dr Jenkins reported:[36]

In the week before Christmas 2020 Mr Smith injured his right knee in a swimming pool. He was reclining on the pool steps with his left fist balled up under his lower back pressing into it for comfort. He recalled shuffling down on the steps to get comfortable. He was unsure what happened to his right knee, however based on the history he may have loaded and/or twisted it somewhat as he did this. He experienced sudden severe pain in the right knee, saying it 'just went'.

Given that this injury occurred because of his lower back condition, I consider that it is related to the lower back condition, i.e., it would not have occurred were it not for his chronic lower back condition which arose directly as a result of the incident at work offshore [sic] on 22/05/2020.

1. Dr Jenkins reported the documents provided to him, in summary, as:
   • Investigations and reports regarding the left groin dated July and August and December 2020 and January 2022
   • Investigations and reports regarding the right knee dated December 2020 and May 2021
   • MRI lumbosacral spine dated 22 February 2021
   • Ultrasound right hip dated 30 April 2021
   • Reports from Professor Krishna Boddu, pain specialist, dated September and October 2020
   • Report of Dr Dayoub dated 4 March 2021 and October 2021
   • Report from Peter Gangemi, physiotherapist, dated August, September, October, November and December 2020
   • Report from Mark Maddison, exercise physiologist, September 2021 and June 2022
   • Report from Rosa McCartney, rehabilitation provider, April 2022
   • WorkCover WA first and progress certificates from various authors and on 'various dates'.
2. It is immediately obvious that none of the reports pre-date the pallet incident, as the arbitrator identified.[38] In his conclusions, Dr Jenkins linked the need for the appellant to relieve his back pain leading to the injury to the knee directly to the pallet incident. It may be understandable that he has made that link given his lack of appreciation of any significant prior low back pain, investigations or its underlying cause.
3. Accordingly, the arbitrator found two foundational failures in relation to Dr Jenkins' report:

(a) no real reference by the appellant to prior existing conditions such that Dr Jenkins would be notified that further medical information or previous history needed to be considered, and

(b) consequently the lack of relevant medical evidence from which Dr Jenkins could make an assessment as to the likelihood of any pre-existing condition affecting the current incapacity, either from that condition itself or any sequelae such as its connection with the incident involving the appellant's right knee.

1. The arbitrator found that the failure to disclose the chronic pre-existing long-standing lower back pain meant that he could not accept Dr Jenkins' resulting opinion regarding the nature, extent and consequences of the lower back injury sustained in the occurrence of 22 May 2020.[39]

1. The arbitrator also summarised the contents of the workers' compensation medical certificates issued by occupational therapist Dr Tan[40] and Dr Wilson and Dr Spurge from February 2021.[41]
2. Of note:
   1. Dr Tan indicated on 12 November 2020 that the appellant should be able to return to his pre-injury duties by January 2021.[42]
   2. Dr Tan's medical certificates indicated that the appellant's lower back pain was improving prior to him injuring his right knee in the swimming pool.[43]
   3. Dr Tan's certificates on 15 December 2020 and 11 January 2021 certified the appellant fit for pre-injury hours performing seated office-based duties, noting that the right knee injury occurred in the swimming pool on 13 December 2020, and that the appellant should not drive, lift, bend, squat, do prolonged walking or standing 'due to his right knee condition' (arbitrator's emphasis).[44]
   4. The certificates of Dr Wilson and Dr Spurge certify a total incapacity for work, however this includes the right knee condition.[45]
   5. Dr Spurge is of the opinion that the lower back pain was and is being exacerbated by the right knee condition which is itself getting worse.[46]
3. I will now summarise the arbitrator's findings in relation to the Issues relevant to this appeal.

Issue A: what was the injury the appellant sustained in the compensable occurrence on 22 May 2020?

1. It was not in issue that on 22 May 2020 the appellant sustained a lower back injury and hernia.[47] It was also not in issue that Mr Smith continues to have low back pain.[48] However, the real issue, the arbitrator identified, was the nature and extent of the compensable lower back injury.[49]
2. The arbitrator identified that the appellant's claim was that his chronic lower back pain that came from the pallet incident has endured and he has a total incapacity for work and a need for medical treatment as a consequence.[50] In contrast, the respondent's position was that the pallet incident caused a now resolved temporary aggravation of pre-existing chronic lower back pain.[51]
3. The arbitrator then considered, in the context of Issue A, the nature and extent of the compensable lower back injury, being relevant to whether that injury, including any sequelae conditions, had resulted in a permanent total incapacity for work. He set out:

(a) Mr Smith's relevant medical history;[52]

(b) the circumstances of the pallet incident on 22 May 2020 and the original claim and acceptance by the insurer GIO;[53] and

(c) after reminding himself of the proper consideration of expert evidence,[54] the reports of:

1. The arbitrator set out his findings in relation to Issue A, including:
   1. The appellant has pre-existing chronic low back pain from which he has never recovered.[58]
   2. Mr Smith sustained an aggravation of the chronic low back pain on 22 May 2020, the aggravation causing at least a partial incapacity for work and a need for treatment for some time.[59]
   3. That the workers' compensation medical certificate issued by Dr Tan on 15 December 2020 certified Mr Smith fit for pre-injury hours however noted the consequences of the right knee injury.
   4. Medical certificates since February 2021 certified a total incapacity for work however this included the right knee condition.
   5. However, finding under Issue B that the right knee injury is not compensable, the arbitrator did not accept the certificates were an accurate reflection of the appellant's incapacity for work resulting from the compensable injuries sustained in the pallet incident on 22 May 2020.[60]
2. The medical evidence led the arbitrator to conclude that the current low back pain was caused by the non-compensable pre-existing chronic low back condition which had been aggravated by the right knee condition.[61]
3. Specifically, the arbitrator:[62]

(a) acknowledged that there was current 'total incapacity';

(b) found that the medical certificates indicate that the total incapacity is partially, at least, due to the right knee condition;

(c) therefore, it was not correct to say that the incapacity results from a compensable injury;

(d) the current and continuing lower back pain is being exacerbated by the knee injury, which is getting worse;

(i) the compensable lower back pain has resolved, and therefore

(ii) any current back pain is as a result of a pre-existing condition causing mechanical lower back pain,

the incapacity is entirely from the knee injury exacerbating the pre-existing lower back pain.

1. Accordingly, in answer to Issue A, the arbitrator found that in the pallet incident Mr Smith sustained a left inguinal hernia requiring surgical repair and an aggravation of chronic lower back pain which has since ceased. He could not find exactly when the aggravation had ceased but found that it was at the latest, 14 December 2022. Therefore, after that time the appellant had returned to pre-existing non-compensable chronic mechanical lower back pain, being aggravated by his non-compensable right knee condition.[63]
2. He considered whether the injury to the right knee was compensable next.

Issue B: did the appellant sustain a compensable condition to his right knee in a swimming pool in December 2020?

1. The arbitrator acknowledged that it was not in issue that:[64]
   1. The appellant injured his right knee in his friend's swimming pool in December 2020.
   2. The right knee condition caused an incapacity for work.
   3. The appellant was in receipt of weekly payments of compensation for the accepted lower back injury throughout the time he was also incapacitated by the right knee condition.
   4. The right knee condition resulted in a need for medical treatment, being some of the expenses sought in the application.
2. The arbitrator set out the relevant question in this issue as whether the right knee injury was 'a consequence of [the compensable] back injury'.[65] That is, if the evidence established that the condition the appellant sustained to his right knee in December 2020 resulted from the accepted lower back injury occurring on 22 May 2020, then the December 2020 right knee condition is compensable,[66] as would then be any consequence of the right knee condition or injury.
3. He set out the law on causation,[67] saying that an incapacity and/or need for medical treatment is compensable if it results from an injury as defined by the Act, citing Leggett v Argyle Diamond Mines Pty Ltd[68] and Napier v BHP Billiton (Worsley Alumina) Pty Ltd.[69] He identified that what is required for compensability is 'a rational relationship between the compensable injury and the claimed incapacity/need for treatment, applying a commonsense evaluation of the causal chain: Kooragang Cement v Bates'.[70]
4. The arbitrator then summarised and analysed the evidence of the incident in the swimming pool. He summarised the appellant's contention as that on the day in question the appellant's back was sore, he made a fist with one of his hands and put it behind his back to apply pressure to his back, sat on a pool step, leaned back, and as he did so his right knee condition suddenly occurred. He could not make a more precise summary of the appellant's contention because of the inconsistencies in the appellant's evidence about the event.[71]
5. However, the arbitrator was not satisfied that the appellant's right knee condition was caused by something he did to alleviate pain in his lower back. This was due to his concerns about the appellant's credibility as a witness generally and the inconsistent accounts he gave to medical professionals about how the incident occurred in the pool; he therefore did not accept the appellant's version of what occurred.
6. It was more likely, he decided, from the description of the pool incident given to the medical practitioners by the appellant, that the appellant was either treading water or standing in the pool and the right knee suddenly became painful. This did not occur, then, from the accepted lower back injury.[72]
7. While not specifically saying so, the arbitrator's findings infer that the arbitrator was not satisfied that the appellant was alleviating pain to his lower back when he was in the swimming pool. This inference can be drawn from his concession in his next paragraphs[73] and his finding that it may have been as late as December 2022 (two years after the swimming pool incident) that the lower back aggravation effect of the pallet incident had ceased, that is, while he accepts that there may still have been lower back pain when the appellant was in the swimming pool, his finding infers that he was not satisfied that the appellant was alleviating that pain, however it came about, on that day.
8. Even had he accepted that the appellant was alleviating back pain, either compensable or otherwise, in the pool, the arbitrator was of the view that the right knee condition was non-compensable in any event, there being no evidence that any pressure was being put on the right leg such that any injury could have occurred; that is, even if the appellant was alleviating his compensable back pain in the pool, there was no connection between the back pain, the measures being taken to alleviate it and the occurrence to the knee, other than 'a tenuous temporal connection'.[74]

Issue C: does Mr Smith have a current injury that is compensable under the Act?

1. Given the arbitrator's finding in relation to Issue B, he concluded that while there is existing chronic mechanical lower back pain and right knee osteoarthritis, with incapacity for work 'to some degree'[75] neither condition is compensable given:

(a) the compensable temporary aggravation occurring on 22 May 2020 of the pre-existing chronic mechanical lower back pain ceased at some point on or before 14 December 2022; and

(b) the right knee condition occurring in December 2020 did not result from a compensable injury,[76] either because the right knee injury did not occur because he was alleviating his back pain, or, even if he was, the mechanism of the knee injury was not connected to the mechanism of alleviating the pain of the back injury.

Issue D: has any current compensable injury resulted in the permanent total incapacity for work of the appellant?

1. Given the arbitrator's findings in relation to the first three issues, the only compensable injury left at the time of writing his decision was the inguinal hernia that was surgically repaired and did not at that point incapacitate the appellant. Accordingly, the appellant was found not to have a permanent total incapacity for work resulting from any current compensable injuries.[77]

Issue E: should an order as to the total liability of the respondent be made having regard to the social and financial circumstances and the reasonable financial needs of the appellant?

Issue F: if an order as to the total liability should be made, in what amount, at what rate and commencing when?

1. Given the arbitrator's findings, he did not need to resolve these issues, however, having considered the appellant's financial need, the arbitrator found that had there been a compensable injury that had resulted in the appellant's permanent total incapacity for work, he would have had no hesitation in finding that an order should be made.[78] Given, however, his finding, he did not need to proceed to determine any amount.[79]

Issue G: should the respondent pay the appellant's outstanding medical expenses for the lower back?

1. Some receipts shown to the arbitrator as part of the appellant's claim were declined for reasons not relevant to these reasons and the arbitrator declined others because they appeared to be in relation to the right knee, which, as he found, was not compensable. Because, as from 14 December 2022 the appellant's compensable lower back injury had ceased, and the arbitrator had found that the respondent was not liable to pay for the medical expenses in relation to the non-compensable condition of chronic low back pain, claims for medical expenses for the lower back pain after 14 December 2022 were dismissed.

Issue I: should any award of compensation be refused on the basis that at the time of seeking employment, the appellant wilfully and falsely represented himself as not having previously suffered the injury?

1. While the arbitrator recognised that given the appellant had not succeeded in any of the claims, it was not strictly necessary to decide this issue, he determined that had it been necessary to so determine, he would have found that the discretion in s 79 of the former Act was enlivened and refused to award compensation which would otherwise have been payable.[80]
2. On 19 June 2019 the appellant completed a pre-employment medical form as part of his recruitment to the respondent. It involved completing the form himself and then consulting with a doctor to finalise the form.
3. At the hearing the respondent tendered the pre-employment medical form, which became Exhibit 2 at the arbitration hearing. The appellant had ticked 'no' to questions about previous compensation or pending industrial claims, as to ever having had any significant or recurrent problems with backache/joint or muscle pain, surgical operations, hospitalisation or having any current illnesses. The arbitrator found that the negative responses to each of those questions was wrong or arguably wrong. Other handwritten answers on the form were wrong or incomplete.[81]
4. The arbitrator was unimpressed by the explanations given in evidence by the appellant about those discrepancies and found that his lower back pain should have been declared, and that that requirement would have been clear to the appellant at the time. The arbitrator was satisfied that, on that form, when the appellant had sought or entered employment with the respondent he wilfully and falsely represented himself as not having previously suffered the lower back injury for which he claimed compensation.[82]
5. The arbitrator found that Mr Smith deliberately concealed this condition from the respondent in the pre-employment medical assessment.[83]
6. The discretion under s 79 being enlivened, he would have determined not to allow the claim in any event.

1. I have set out the grounds of appeal in full. I will summarise them when I come to individually address them.

1. The learned Arbitrator failed to apply the correct legal test in Wilson v Bentley Health Service (WACCC31-2007, McCann P, 6 July 2007, unreported) in determining whether the appellants incapacity resulted from his compensable injury.

1.1 The appellant referred to the above test in his submissions, but the learned Arbitrator did not refer to or apply that test in his decision.

1.2 The learned arbitrator erred at paragraph [120] of his decision where he found, the current low back pain is caused by the non-compensable pre-existing chronic low back condition which has been aggravated by the right knee condition.

1.3 The correct issue for determination was whether the applicants incapacity resulted from his compensable injuries, not the cause of his current low back pain. The correct comparison was between pre-injury and post-injury capacity, not between pre-injury and post-injury symptoms.

1. The learned Arbitrator failed to apply the correct legal test in Massih v Electricity Networks Corporation t/as Western Power [2016] WADC 146 (employer to disentangle competing causes of incapacity with reasonable precision).

2.1 The applicant referred to the test in Massih in his submissions, but the learned Arbitrator did not refer to or apply that test in his decision.

2.2 The learned Arbitrator erred at paragraph [122] of his decision where he found, An aggravation of chronic lower back pain. This aggravation has since ceased. I do not make a finding when that exactly occurred although I accept Dr Dayoubs opinion expressed in his report dated 14 December 2022 that the aggravation had ceased by then.

2.3 Dr Dayoubs opinion is not satisfactory evidence to discharge the respondents burden of disentangling competing causes of incapacity with reasonable precision because Dr Dayoub did not explain with reasonable precision how the appellants incapacity no longer resulted from his compensable injuries.

1. The learned Arbitrator failed to apply the correct legal tests in Ward v Corrimal-Balgownie Colleries Ltd [1938] HCA 70; (1938) 61 CLR 120), Wilson v Bentley Health Service (WACC C31-2007, McCann P, 6 July 2007, unreported), Treasure v WA Country Health Service (WACC C17-2010, McCann P, 26 November 2010, unreported) and Lockwood-Hall v BHP Billiton Nickel West Pty Ltd (WACC C5-2012, McCann P, 18 May 2012, unreported) when considering pre-existing conditions under section 217.

3.1 The appellant referred to the above tests in his submissions, but the learned Arbitrator did not refer to or apply those tests in his decision.

3.2 The learned arbitrator erred at paragraph [120] of his decision where he found, the current low back pain is caused by the non-compensable pre-existing chronic low back condition which has been aggravated by the right knee condition.

3.3 The respondent was required to take the appellant as it found him with his pre-existing back condition and pre-existing right knee condition and be liable for compensation if the appellants compensable injuries aggravated or accelerated those conditions or if those conditions aggravated or accelerated the compensable injuries. The learned arbitrator failed to apply that legal test and so erred at paragraph [132] of his decision in finding that the appellants right knee condition was not aggravated by a compensable injury.

3.4 The learned Arbitrator erred by requiring a quality of evidence unreasonably precise (contrary to the correct legal test in Massih) from the appellant of how exactly he injured his right knee in a swimming pool, when the only conclusion open on the evidence was that the appellants right knee was injured by some kind of mechanism while he was alleviating back pain in a swimming pool.

3.5 The learned Arbitrator erred by requiring a quality of evidence unreasonably precise when he considered Dr Jenkins evidence at paragraphs [86] to [89] of his decision.

3.6 A compensable injury need not be the actual physiological cause of the current incapacity for the incapacity to be compensable - the current incapacity can be caused by a pre-existing disease that was aggravated or accelerated by a compensable injury. The learned Arbitrator erred at paragraph [120] of his decision because he failed to apply that legal test.

3.7 Even if the compensable injuries did not aggravate or accelerate those conditions, those conditions in and of themselves do not prevent an extension to the prescribed amount under the test in Lockwood-Hall. The learned Arbitrator failed to consider that test.

1. The learned Arbitrator failed to consider the appellants evidence to find suitable employment.

4.1 The learned Arbitrator erred at paragraph [122] of his decision where he found, An aggravation of chronic lower back pain. This aggravation has since ceased. I do not make a finding when that exactly occurred although I accept Dr Dayoubs opinion expressed in his report dated 14 December 2022 that the aggravation had ceased by then.

4.2 The learned Arbitrator erred at paragraph [143] of his decision where he found, The compensable injury to the lower back was in the nature of an aggravation of chronic lower back pain that had ceased on or before 14 December 2022.

4.3 As the result of the above errors, the learned Arbitrator failed to consider the appellants evidence to find suitable employment, especially from around 26 July 2022 when the prescribed amount was exhausted to 14 December 2022, and that the appellant failed to obtain suitable employment either because of his compensable injuries or he was not qualified.

4.4 Despite those errors, the learned Arbitrator failed to apply the correct legal test in R v Hill [2012] ACTSC 121 (presumption of continuity), from 26 July 2022 to 14 December 2022. This test was referred to in the appellants submissions, but was not referred to or applied in the learned Arbitrators decision.

4.5 As the result of the above errors, the learned arbitrator erred again at paragraph [147] of his decision where he found, From 14 December 2022, Mr Smiths compensable lower back injury had ceased. From that date, FOS are not liable to pay for the medical expenses in relation to the non-compensable condition of chronic low back pain. Mr Smiths claims for medical expenses for the lower back pain after 14 December 2022 is dismissed.

1. The learned Arbitrator incorrectly applied section 79 in refusing to award compensation for an extension to the prescribed amount.

5.1 The appellant proved that he sustained compensable injuries at paragraphs [28], [77] and [122] of the arbitrators decision that were the result of lifting heavy pallets that were outside the scope of his duties.

5.2 The learned Arbitrator found at paragraph [136] of his decision that the compensable temporary aggravation occurring on 22 May 2020 of the pre-existing chronic mechanical lower back pain ceased at some point on or before 14 December 2022.

5.3 The learned Arbitrator made no finding that the award of compensation would be refused under section 79 from the date of the compensable injuries on 22 May 2020 until the prescribed amount was exhausted around 26 July 2022.

5.4 It follows that if compensation was properly paid from 22 May 2020 until the prescribed amount was exhausted around 26 July 2022, section 79 could not then be applied to refuse the award of compensation for an extension to the prescribed amount after 26 July 2022.

5.5 The learned Arbitrator erred at paragraphs [150] and [157] of his decision by finding that section 79 was enlivened.

5.6 If section 79 was enlivened, the learned Arbitrator failed to apply the correct legal tests in Re Iliadis v Comcare (1996) 41 ALD 576, Re Schofield v Comcare [1995] AATA 42; (1995) 38 ALD 124, Anderson v Mineral By-Products Pty Ltd (1987) 8 WCR(WA) 37 when exercising his discretion under section 79.

5.7 The appellant referred to the above tests in his submissions, but the learned Arbitrator did not refer to or apply those tests in his decision.

5.8 There was no evidence that had the respondent known about the appellants previous back and right knee history that it would not have employed the appellant.

5.9 The learned Arbitrator failed to consider that the appellant was certified by a medical practitioner of the respondents choice to be fit for work as an offshore field technician based on a thorough physical medical examination.

5.10 The learned Arbitrator failed to consider that the respondent failed to put the appellants past medical records to the above medical practitioner to see if he still would have certified the appellant fit for work as an offshore field technician, and so failed to draw a Jones v Dunkel inference against the respondent.

5.11 The learned Arbitrator failed to consider that the appellant had full capacity to work as an offshore field technician until the respondent instructed him to lift heavy pallets outside of his usual duties because the respondent was moving premises and did not want to hire professional movers.

5.12 The learned Arbitrator failed to consider that other co-workers refused to lift the heavy pallets because that was well outside the scope of their usual duties.

5.13 The learned arbitrator failed to consider Dr Selvendras report of 20 October 2022 (which was not mentioned in his decision) which provided that the appellants back injury of 22 May 2020 was to the left side of his lower back (which he had not had pain before), not to the right side of his lower back (which she had previously treated the appellant for) In other words, the appellant had a different back injury.

1. The appellant sought orders that:
   1. The respondent pay the appellant weekly payments fixed at $182,993.25.
   2. The respondent pay the appellant's expenses related to his right knee surgery.
   3. The respondent pay medication expenses.
   4. In the alternative, the application be remitted to another arbitration for determination according to the correct legal tests.
   5. The respondent pay the costs of the appellant's arbitration application and appeal.

The requirement for the appeal to involve a question of law

1. Mr Smith requires leave to appeal against the arbitrator's decision. In order to justify a grant of leave, the appeal must concern an issue of law. An appeal involves a question of law when either an error of law, or error of mixed law and fact, is involved.
2. In each of the Grounds 1 - 4 the appellant has alleged an error in applying a legal test. However, underlying those alleged errors are alleged errors of fact.
3. A decision of a tribunal will be infected with jurisdictional error when it is irritational, illogical and not based on findings or inferences of fact supported by logical grounds.[84] It is intended that a statutory power will be exercised reasonably and that an abuse of power, or an unreasonable exercise of that power, will be an error of law.[85]
4. While many of the particulars of the appellant's grounds contain complaints which are alleged errors of fact, I have taken it that the appellant says that the findings of fact are so illogical that they have led the arbitrator into making errors of law, or into jurisdictional error. The appellant appears to be arguing that the decisions of fact were made because the arbitrator misconstrued the relevant tests, or did not apply them, to the issue to which the facts were relevant, or, as a result of the errors of fact, the arbitrator applied the incorrect tests, or the correct tests incorrectly. While the respondent in oral submissions argued that some of the submissions made by the appellant at the hearing of the appeal were against factual findings of the arbitrator, its submissions did not go so far as to say that leave could not be granted.

1. None of the grounds of appeal succeed, for the following reasons.

1. The appellant agreed at the hearing of the appeal that there is no separate test of causation in Wilson v Bentley Health Service[86] as it relates to current incapacity. Therefore, the appellant's primary contention in this ground[87] is that:
   1. While the arbitrator stated the correct test, in applying that test he asked himself the wrong question.[88]
   2. The arbitrator relied on the opinion of a medical expert when he should have formed his own view.[89]
   3. The arbitrator in Wilson made the same error.[90]
   4. Had the arbitrator in the present case had regard to Wilson, the arbitrator would have appreciated that the question for determination, that is, the correct application of the test, is a more precise test,[91] which is whether the incapacity results from his compensable injury, not whether the cause of the lower back pain was a non-compensable, pre-existing chronic lower back injury as aggravated by a right knee condition.[92]
2. That is, it is a question of capacity, not symptoms.
3. The failure to apply the test properly, said the appellant, is illustrated by the fact that the arbitrator, despite being referred to it, did not mention Wilson in his reasons for decision, in the question the arbitrator posed for the resolution of Issue C, or in the arbitrator's determination set out at [120] of his reasons.
4. To determine this ground I have considered whether Wilson provides a more 'precise' test, or at least guidance as to how the relevant question on causation should be asked and whether the arbitrator did not ask the correct question.

1. Under s 21 of the former Act, an employer is liable to pay compensation from the date of incapacity resulting from the injury. There is a clear requirement for a link between the relevant injury and the incapacity.
2. The object of the enquiry is to determine whether compensation is payable by the employer because the worker's incapacity was causally related to an injury suffered in the course of employment.[93] As the appellant has identified, it is the incapacity that is the focus of the enquiry, not the injury itself.[94]
3. In Wilson, McCann P referred to Leggett and Kooragang Cement Pty Ltd[95] as having been referred to by the arbitrator in that matter and as containing the relevant principles and test. He noted that from those authorities, and others which confirm them:
   1. The question of whether incapacity results from the impugned work injury is a question of fact, however a point will be reached in the facts where the link in the chain of causation becomes so attenuated that, for legal purposes, it will be held that the causative connection has been snapped. When determining whether this has occurred, the decision maker must return to the question: does the disputed incapacity result from the work injury which is impugned.[96]
   2. If an incapacity exists, it is not necessary that the injury should be the sole cause of it. It is sufficient if it is a material contributing cause, which is a question of fact in each case to be decided on broad commonsense lines.[97]
4. Accordingly, for the appellant to have succeeded at first instance, in the present case he would need to have demonstrated that at the relevant time, being the time of the claim for ongoing compensation, he had sustained a compensable injury and an ongoing incapacity that results from that injury. Therefore, while the original injury may have resolved, there may still be injury caused by the original injury which in turn causes an ongoing incapacity.
5. Relying on these authorities, McCann P in Wilson has not created a new or refined or more precise test, but rather an explanation of the application of the test in the context of the facts of that case.

Irrespective of whether the arbitrator specifically referred to Wilson, has the arbitrator applied the test of causation in a manner consistent with Wilson?

1. In Wilson the compensable injury was trauma to the right knee, inflicted after the worker had had medical advice that he required knee replacements. He remained incapacitated post trauma, even though, the arbitrator found, the damage to the knee from the trauma had resolved. The arbitrator found that there was no evidence that the compensable injury had caused ongoing injury or disease.
2. The complaint on appeal in Wilson was that the arbitrator erred in the application of the relevant tests by losing focus on the ultimate issue, being whether the worker's current condition resulted from the work injury.[98]
3. Similarly in the present case, the appellant complains that the arbitrator did not ask the correct question, being whether the appellant has an incapacity resulting from his injury, rather than does Mr Smith have a current injury (the appellant's emphasis) that is compensable under the Act.
4. As McCann P identified in his reasons, the arbitrator in Wilson did at some point direct herself that the question is whether the compensable injury is contributing to the incapacity, and that that question was consistent with the principles enunciated in Leggett.[99]
5. The error identified in Wilson, however, was that the arbitrator based her application of that test on the erroneous finding that there was no evidence to support a finding that the work injury caused an aggravation or acceleration of the pre-existing disease present in that worker. McCann P was of the view that there was some evidence to support such a finding, being that the worker was still incapacitated for work. While that may not have been conclusive proof that the compensable injury, or its consequences, was the cause of the current incapacity, it was, nevertheless, capable of being evidence of the causal connection, rebuttable by evidence from the respondent.[100]
6. It appears that the arbitrator in Wilson had made the error by determining that as surgery was inevitable, and the effect of the trauma had resolved itself, there was no connection between the compensable injury and the ongoing incapacity resulting from the prior disease. McCann P found that there was the possibility, overlooked by the arbitrator, that the trauma had accelerated the need for surgery and therefore the incapacity. If that was the case, then there was a causal connection between the compensable injury and the current incapacity.
7. By asking about the current injury, the arbitrator had failed to consider the possibility that although the damage to the knee caused by the trauma had resolved, the trauma had nevertheless contributed to the exacerbation or acceleration of the underlying disease, such that surgery was required much sooner than would otherwise have been, and the hastened need for that surgery was the cause of the incapacity.

Does the use of the word 'injury' as opposed to 'incapacity' reveal error?

1. In his written submissions the appellant in the present case complains under Ground 1 that the arbitrator misapplied the test of causation in resolving Issue C. However, the question complained of is 'Does Mr Smith have a current injury that is compensable'? Viewed in isolation, that question may focus on the wrong factors; 'current' and 'injury' suggest that the focus is on whether there is a specific injury, currently existing, which is causing the post injury symptoms, and the incapacity. If that is the focus, then the question may have led the decision-maker into error by thinking that it is any current injury itself which must be specifically compensable, as opposed to incapacity currently existing which can be related to a previous compensable incident.
2. However, that is only the case if the question posed by the arbitrator is viewed in isolation. The consideration of Issue C follows the consideration of Issue B: whether the appellant suffered an injury to his right knee that is compensable. The consideration of Issue D: 'has any current compensable injury resulted in permanent total incapacity for work?' follows the consideration of Issue C.
3. Unlike the arbitrator in Wilson, the arbitrator in the present case has had regard to the capacity of the worker post possible resolution of the pallet incident back injury, and recognised that the incapacity of the worker post resolution of the original injury is a relevant factor in determining whether the current incapacity is compensable. In his exploration of Issue B, the arbitrator said, in the context of the finding that the back injury from the pallet incident had resolved:[101]

The relevant test is whether it can be said that the right knee condition and accompanying incapacity and need for medical treatment results from the accepted lower back injury.

1. As I have set out at [67] of these reasons, the arbitrator acknowledged in his findings on Issue C that there is existing incapacity for work. He also set out the test for causation.[102] I have set out at [20] of this decision, the arbitrator's findings regarding the links between the injuries.
2. Incapacity from continuing back pain would only be compensable if it is a continuation of the back pain caused by the pallet incident, or the injury caused by the pallet injury exacerbated a pre-existing back injury, and that exacerbation continued, or the back pain from the incident has sequelae which are contributing to the incapacity. The arbitrator determined that the appellant had ongoing mechanical lower back pain, however, based on Dr Dayoub's opinion that while the pallet incident did exacerbate the appellant's pre-existing chronic mechanical lower back pain, that exacerbation ceased at some point on or before 14 December 2022.[103]
3. Having considered the medical evidence in relation to his medical history and the evidence of Dr Jenkins, Dr Dayoub and Dr Phillips, discounting Dr Jenkins' evidence, the arbitrator found that the right knee condition and accompanying incapacity and need for medical treatment do not result from, and therefore are not sequelae to, the accepted lower back injury.[104]
4. Any incapacity due to the condition to the right knee is only compensable if the condition results from the pallet incident, being the original compensable incident, either because the appellant was doing something in the pool that related to the injury or symptoms from the compensable incident, whether or not it still existed at the time, resulting in injury to the right knee, or the pallet incident exacerbated or accelerated a pre-existing disease to the right knee resulting in more serious treatment sooner (as was the possible case in Wilson), or perhaps the pallet incident exacerbated the pre-existing back injury, and the exacerbation caused the injury to the knee.
5. The arbitrator found that it is the pre-existing chronic lower back pain that is being aggravated by the knee injury.[105] As he found that the knee injury occurred independently of the pallet incident,[106] he concluded that the current back pain is not caused by a compensable incident; the arbitrator finding the injury itself to the right knee not compensable, any incapacity from either possibility in relation to the knee was not possible in the case of the appellant.
6. Further, the pallet incident back injury having resolved, neither was that the cause of the incapacity.
7. In asking the question in Issue C, and acknowledging incapacity in Issues B and D, the arbitrator recognised that while there must be an injury leading to the incapacity, the injury may have resulted from an injury that is compensable. An injury cannot be compensable if it does not result from the original compensable incident, in this case, the pallet incident. In other words, the arbitrator did ask: is what is causing his current incapacity linked to a compensable incident?
8. It is in that nature that the arbitrator has focused on pre- and post injury incapacity, rather than symptoms, in coming to his findings, and not fallen into the same error as the arbitrator in Wilson, or any error in that regard. Even if there was pre-injury capacity, as the appellant says he had, that does not mean that any new incapacity must be caused by the pallet incident injury. The arbitrator, relying on the medical evidence, as he was entitled to do, was satisfied that the respondent rebutted any such contention.

Does it matter that the arbitrator did not refer to Wilson?

1. In finding that the arbitrator applied the correct test, and focused on the correct question, in relation to the question of incapacity resulting from a compensable injury, in my view there is no consequence to him not referring to Wilson.
2. While leave is granted because the ground involves a question of law, Ground 1 fails.

1. The appellant's primary contention in this ground is that the arbitrator failed to apply the correct test in relation to the employer disentangling competing causes of incapacity with reasonable precision, leading him to rely on the evidence of Dr Dayoub in error.
2. The correct test, says the appellant, is that in Massih v Electricity Networks Corporation t/as Western Power,[107] and the failure to apply the correct test is illustrated by the fact that the arbitrator, despite being referred to it, did not mention Massih, particularly in the arbitrator's determination set out at [122] of his reasons.
3. The respondent concedes that the appellant referred the arbitrator to Massih in his submissions, and that the arbitrator did not refer to Massih in his reasons for decision. However, the respondent says that does not matter - the arbitrator has correctly applied the burdens applicable to each party.[108]
4. The appellant in effect made two complaints about the arbitrator's application of the burden:

(a) the arbitrator did not identify the correct legal test for the employer to disentangle the causes; that is, it is not enough that the employer simply lead evidence - it must be of a certain quality;[109] and

(b) the arbitrator erred by relying on the opinion of Dr Dayoub, as Dr Dayoub was not sufficiently precise - he provided no robust analysis of the cessation of the pallet incident injury symptoms, he provided no evidence of a supervening act, and he did not explain how the compensable injury ceased and the non-work condition took over.[110]

1. To answer these complaints I will consider whether, despite no reference to Massih, the arbitrator applied the correct burdens to each party, and whether the arbitrator erred in relying on the opinion of Dr Dayoub to find that the respondent had discharged its burden.

1. In Massih, her Honour Judge Schoombee summarised the burdens of each party as follows:
   1. In tort law the plaintiff, or worker with respect to workers' compensation proceedings, carries the burden of proving that their incapacity was caused, in the sense of being materially contributed to, by the work injury. The defendant, or employer, has an evidentiary burden where it is claimed that pre-existing conditions would in any event have resulted in the incapacity manifesting itself at the time, such that the compensable injury is not the cause of the current incapacity.[111]
   2. Practically, the employer must present evidence to show that the pre-existing degenerative condition was the sole cause of the worker's 'symptomology/incapacity' arising at the relevant time and that symptoms would have manifested themselves in any event by a particular date without the work accident having occurred.[112]
   3. Where there are competing causes to the incapacity, it is the employer who should be required to do the disentangling and to exclude the operation of the accident as a contributory cause, although this is an evidentiary burden, not a legal burden.[113]
2. Despite those references, her Honour did not refer to, as the appellant in this case has, the evidentiary burden of the employer as requiring the production of evidence which gives 'reasonable precision'. That phrase comes from Purkess in discussion of Watts, the plurality noting that the employer's evidentiary burden is not discharged simply by the respondent suggesting that there was another cause of the worker's incapacity; the capacity must be the subject of evidence 'which, if accepted, would establish with some reasonable measure of precision, what the pre-existing condition was and what its future effects ... were likely to be'.[114]
3. Therefore, it does not appear that Massih contains an actual test; her Honour has merely stated where the legal and evidentiary burdens lie.
4. Nevertheless, what seems clear is that where there may be competing causes to a worker's injuries, the employer bears an evidentiary burden to disentangle them, the standard being 'with a reasonable measure of precision'. However, the legal onus remains with the worker to prove that the accident made a material contribution to the worker's disability.[115]

1. While the arbitrator does not specifically refer to the relevant burdens or any standards for those burdens, in my view the structure of his reasons for decision imply that he was both aware of and applied those burdens appropriately.
2. In his consideration of Issue A[116] the arbitrator notes that it is not in dispute that the appellant sustained compensable injuries in the pallet incident being a lower back injury and a hernia injury. He identified that the appellant says he has chronic lower back pain that results from the occurrence, and the employer's 'position' is that the occurrence caused a now resolved temporary aggravation of pre-existing chronic lower back pain.
3. Identifying that the respondent has a 'position' implies that the arbitrator understands that the respondent has in effect a position to defend. In that sense, therefore, the arbitrator appears to accept that the appellant has discharged one aspect of his legal burden.
4. The arbitrator signified that it is necessary to determine the nature and extent of the compensable lower back injury 'because it is relevant to whether that injury (including any sequelae conditions) has resulted in a permanent total incapacity for work'.[117] By his identification of the law of causation[118] it appears that the arbitrator was aware that there was only a need for a material contribution by the compensable injury to the current incapacity.
5. The arbitrator then set out the appellant's relevant medical history, including cross-examination at the hearing. He found that the appellant:

(a) reported a history of long-standing low back pain to Dr Yong in December 2019;[119]

(b) requested Dr Yong prescribe morphine patches because he had lower back pain;[120]

(c) consulted with general practitioners in April, May and December 2019 because he had lower back pain;[121] and

(d) was referred to a neurosurgeon in April 2019 and another in December 2019 because of his ongoing lower back pain.[122]

1. In his reasons the arbitrator identified that:[123]

(a) the appellant's contention is that the lower back injury he sustained in the pallet incident has endured and he has a total incapacity for work and a need for medical treatment that results from the injury; and

(b) the respondent's contention is that the appellant has not proved that he has a current total incapacity caused by the pallet incident and has not proved that the medical treatment he seeks payment for results from the accepted lower back injury.

This latter statement is consistent with the appellant maintaining the legal burden. It is put in absolute terms because the position of the respondent was that the compensable injury and any consequential effect, or sequelae, were no longer present, not that there may be some, but perhaps insufficient, contribution.

1. The arbitrator then set out and discussed at length the expert evidence, being the evidence of Dr Jenkins, Dr Dayoub and Dr Phillips.
2. He then found that the appellant had suffered low back pain and continues to do so.[124] He says that '[t]he medical evidence leads me to conclude the current low back pain is caused by the non-compensable pre-existing chronic low back condition which has been aggravated by the right knee condition'. He rejected the appellant's submission that because he has suffered low back pain since the compensable occurrence the low back pain is compensable.
3. Having relied on the medical evidence of Dr Dayoub and Dr Phillips and the medical certificates of Dr Tan in coming to that conclusion, the arbitrator has used that evidence to counter the contention of the appellant that the pallet injury is enduring. Whether that evidence was to the requisite standard is another question, however, by that structure and the resolution of that question per se, the arbitrator has proceeded to determination on the basis that the respondent had called or relied on evidence of the pre-existing back pain, the pallet injury, the subsequent knee injury and the enduring incapacity, thereby, without specifically saying so, recognising and applying the appropriate burdens.

1. As I have identified, the appellant is correct in saying that it is not sufficient for the employer to simply lead evidence - it must be of a certain quality. The question, really, in this ground, is, was the evidence relied on by the arbitrator of that quality? To determine that it is necessary to review the arbitrator's findings on the medical evidence.

The arbitrator's findings on the medical evidence

1. I have already referred to the arbitrator's general findings on the appellant's health pre-May 2020.
2. Dr Dayoub reviewed the appellant on 7 December 2022 and reported on 14 December 2022. The arbitrator records that Dr Dayoub reports that:[125]
   1. Clinical records suggest that the appellant had chronic lower back pain for many years prior to the pallet incident.
   2. He had required cortisone injections and was recommended to see a surgeon for that pre-existing back pain.
   3. 'The workplace incident that occurred on [22] May 2020 may have caused a temporary aggravation of the pre-existing lower back pain'.
   4. However, such aggravation had ceased 'by now'.
3. From Dr Dayoub's opinion, the arbitrator drew the following conclusions:

(a) the aggravation of chronic lower back pain had ceased although he could not make a finding when that exactly occurred other than to say that it had ceased by or on or before 14 December 2022;[126] and

(b) any claims for lower back pain after 14 December 2022 are dismissed.[127]

Was Dr Dayoub's evidence of sufficient quality for the arbitrator to rely on it?

1. The appellant says that the inability to determine a precise date that the lower back pain symptoms returned to pre-existing non-compensable chronic mechanical lower back pain, and the lack of any specific medical discussion of how he knows that the pallet incident injury had resolved acknowledges the imprecision, and lack of robust analysis, of Dr Dayoub. The lack of precision means that the arbitrator should not have relied on Dr Dayoub's opinion, as his evidence did not satisfy the requirement that the evidence led by the respondent must identify the pre-existing condition and its future effects, both as to their nature and their future development and progress, with some reasonable measure of precision.[128]
2. Further, the appellant says that the finding in relation to the post pallet incident incapacity is contrary to the fact that the appellant had full capacity to work as an offshore field technician prior to the pallet incident but at the date of the arbitrator's decision, the appellant was unemployable and couch surfing, such evidence being capable of supporting a finding that the appellant has not returned to his pre-existing non-compensable chronic lower back pain.[129]
3. Neither, the appellant says, has there been any supervening act breaking the chain of causation and therefore the causal chain remains intact.[130]
4. There are two parts to the arbitrator's acceptance of Dr Dayoub's opinion which are complained of by the appellant:

(a) why the arbitrator accepted it as being credible; and

(b) whether it was of sufficient precision to satisfy the evidentiary burden.

1. The acceptance of Dr Dayoub's opinion relies not only on the report itself of that doctor, but on the opinion of Dr Phillips and the other medical evidence before the arbitrator, and a rejection of the opinion of Dr Jenkins.
2. Dr Jenkins reported that the appellant denied any lower back pain or abdominal symptoms immediately prior to the pallet incident, however noted that in approximately 2018 there was 'Low back pain with cortisone injection, recovered'.[131] As I have identified, the arbitrator found Dr Jenkins proceeded on the wrong basis that the appellant was entirely fit and well before the pallet incident.[132]
3. That meant, he found that he could not accept Dr Jenkins' opinion regarding the nature and extent of the lower back injury sustained in the pallet incident.[133]
4. In contrast, the arbitrator accepted the opinions of Dr Dayoub and Dr Phillips as being based on more (particularly regarding prior to the pallet incident), and more credible (and not just the appellant's self-reported history), information.
5. In his report of 25 October 2021 Dr Dayoub concluded that the MRI scan revealed the presence of a multilevel degenerative disease and a potential impingement of the left L4 nerve. As I have identified, given the lack of pre-incident medical records, at that stage Dr Dayoub was unable to reach a conclusion about whether those symptoms were connected to the pallet incident.
6. Dr Phillips concluded that if the appellant's complaints in 2023 were genuine, then the pre-existing pathology explained those complaints, rather than the work incident of 22 May 2020;[134] there was no evidence of an acute injury.
7. The arbitrator found that, in fact, the appellant was not entirely fit and well prior to the pallet incident, specifically, that he had been suffering long-standing lower back pain, last reported in December 2019.
8. The arbitrator based this finding not only on the opinions of Dr Dayoub and Dr Phillips, but on the other medical evidence he extensively reviewed and summarised in his decision.
9. On the basis of the medical history provided to each of the doctors, the arbitrator was entitled to reject the opinion of Dr Jenkins as being unreliable, and accept the opinion of Dr Dayoub and Dr Phillips as being based on reliable information.
10. Each of them established what the pre-existing condition was by examining the medical records pre- and post incident, and relying on their own examinations.

1. The arbitrator set out the law in relation to the acceptance of expert evidence.[135] Neither party sought to impugn his recitation of the law in the appeal. Specifically, the arbitrator referred to Minister for Education v Shire of Northam[136] in which his Honour Judge McCann said that opinion evidence is admissible for the purpose of assisting the court to make findings of fact and the assistance to be derived from expert evidence may also depend to some extent on the degree of specialisation involved in the relevant expert field.[137] It is not for the decision-maker to form and rely on its own view of the subject of the expert evidence after being educated by the expert; particularly in very technical or esoteric areas, the court is entitled to place significant weight on the expert evidence.[138]
2. In the present case, the arbitrator was entitled to find, having regard to the medical evidence set out in his reasons for decision[139] that there was a pre-existing mechanical lower back injury. That being found as a fact, the next question was what the effect was of the pallet incident on that condition. Dr Dayoub identified the relevant question as 'whether the degenerative disease has been rendered symptomatic as a result of the workplace incident of 22 May 2020'.[140] Dr Phillips identified that some individuals with similar changes can be symptom-free. The arbitrator found, again based on the medical evidence, that the pre-existing condition was exacerbated by the pallet incident. That finding indicates not only a finding of fact in relation to the pre-existing condition, but an acknowledgement that the apparent capacity of the appellant pre-22 May 2020 was a relevant factor in determining whether the post pallet incapacity was linked to the pallet incident.
3. Any such link, being, as the arbitrator found, an exacerbation, however, does not necessarily continue indefinitely. Having access to the pre-pallet incident clinical records and the mechanism of the December 2020 knee injury, Dr Dayoub found:[141]

(a) the exacerbation was temporary, and will have ceased 'by now';

(b) the subsequent knee injury altered the appellant's gait;

(c) the altered gait caused an aggravation of the chronic lower back pain; and

(d) any exacerbation of the pre-existing lower back pain is due to the altered gait, that is, secondary to the non-work related injury of the right knee which occurred on 12 December 2020.

1. Further, once he had accepted the opinion of Dr Dayoub and Dr Phillips, and made findings of fact as to whether it was the pallet incident which was the cause of the current incapacity, the arbitrator was entitled to accept the medical evidence that, in the opinion of Dr Dayoub, by the time the appellant had visited Dr Dayoub in December 2022, the pallet injury had resolved, and make a finding of fact accordingly.
2. The appellant's contention at first instance was that:

(a) there was limited if any pre-existing back pain - that was rejected by the arbitrator;

(b) the pallet incident caused mechanical lower back pain - that was accepted by the arbitrator;

(c) the right knee pool incident was a sequela to the pallet incident, in that it occurred when the appellant was in a pool relieving the pain from his back - that was rejected by the arbitrator because:

(i) given the inconsistencies in his evidence, the best he could find was that the appellant's evidence at the arbitration hearing was that he sat on a step in the pool to alleviate his back pain and suddenly his leg 'just blew';[142]

(ii) even if that were the case, the description given by the appellant is such that the pain in his back has nothing to do with the position of his right leg, nor the 'blowing';[143] however, in any event,

(iii) reports the appellant gave to medical professionals were that he was standing or treading water in the pool and he felt pain in the right knee,[144] such that even on the appellant's version to medical professionals there is no connection between the back injury and the injury to the knee, as he was not relieving the pain;[145] and

(d) the current incapacity and medical expenses were caused by or due to the connection between the pallet incident and the right knee injury - as a result of the arbitrator's findings he rejected this contention.

(a) the connection between the right knee injury and the pallet injury; and

(b) by the medical evidence, the continuing effect of the pallet injury,

there was nothing for the respondent to 'unravel'; there were no competing causes. Seen in that light, it did not matter when precisely the aggravation ceased exactly - it was sufficient that the effects of the pallet injury had ceased when the claim for the continuing payment was made.

1. Combined, Dr Dayoub and Dr Phillips have given detailed consideration to the symptoms suffered by the appellant at the time at which they reported on him. While it is the case that neither has identified a precise time at or mechanism by which the effects of the pallet incident on the pre-existing lower back condition abated, nor identified in their reports the consequences of the medical diagnosis on the health of the appellant, such position is not required.
2. Dr Dayoub's opinion was that the altered gait was the current cause of the appellant's lower back symptoms, exacerbating the pre-existing lower back condition. Dr Phillips, it appears has been unable to identify exactly what the cause of the current pain is, other than ruling out any injury in May 2020, but preferred the view that it is in fact the underlying pre-existing degenerative changes themselves which are the cause.
3. The arbitrator accepted that the appellant had not returned to his pre-pallet incident capacity. None of the doctors said that he had. Dr Dayoub and Dr Phillips, however, found that the right knee pool incident had resulted in an exacerbation of the pre-existing back pain, such that any current incapacity was a result of the combination of those two factors, where the pallet incident pain and pallet incident aggravation of the pre-existing back pain had ceased.
4. To invoke the 'disentanglement' metaphor, where there were threads to disentangle, the respondent did so with the medical reports from Dr Dayoub and Dr Philips and the workers' compensation certificates. Having disentangled them, there were no threads connected from the pallet incident to the current incapacity. The arbitrator considered at length the medical evidence, some of which was put on by the respondent and the consistencies and inconsistencies therein. In that sense, the respondent discharged its evidentiary burden, and the arbitrator was able to make sufficiently precise findings of fact as to the cause of the current incapacity.
5. Given the arbitrator found no connection between the pool incident and the low back pain, there was no need for any more precise timing or description or diagnosis. While it is the case that neither the arbitrator nor doctors have specifically identified future effects of the pre-existing low back pain, there was no need to once a finding was made that the knee injury was not connected to the compensable pallet incident, and that the pallet incident effects had resolved. The arbitrator was entitled to rely on the medical opinions drawn on the analysis of all of the pre- and post incident medical material.
6. Accordingly, the evidence did identify with reasonable precision what the pre-existing condition was, and rejected the possibility that its future effects either no longer existed, or that the pallet incident effects were in any way entangled still with the pre-existing condition.
7. The arbitrator recognised and applied the respondent's evidentiary burden. Having done that, it was for the appellant to satisfy the arbitrator that the pallet incident made a material contribution to the appellant's incapacity. The arbitrator was not satisfied that he had. Referring to Massih would not have changed that outcome.
8. The arbitrator's findings on the facts were logical and supported by the evidence - he did not rely on Dr Dayoub's opinion in error, and he applied the correct test, in the correct manner. Therefore, while leave is granted because the ground involves a question of law, Ground 2 fails.

1. The appellant's primary contention in Ground 3 is that the arbitrator failed to apply the correct tests when considering pre-existing conditions under s 217 of the former Act. The appellant says that the correct test is contained in:
   • Corrimal-Balgownie
   • Wilson
   • Treasure v WA Country Health Service[146]
   • Lockwood-Hall v BHP Billiton Nickel West Pty Ltd.[147]
2. The appellant also refers to the test in Massih as being relevant to this ground.
3. The failure to apply the correct test, the appellant says, is illustrated by:

(a) despite being referred to them, the arbitrator failing to mention any of these cases in his reasons for decision;

(b) requiring a quality of evidence unreasonably precise when considering the evidence of Dr Jenkins;

(c) requiring a quality of evidence unreasonably precise when considering the evidence as to how the appellant injured his knee;

(d) failing to recognise that a compensable injury need not be the actual physiological cause of the current incapacity for the incapacity to be compensable; and

(e) that even if the conditions were not accelerated or aggravated by the compensable injury, an extension to the prescribed amount is not precluded.

1. In written submissions the appellant complains that:

(a) none of the experts for the respondent took an accurate history of how the right knee injury occurred;[148]

(b) that is because none of the experts for the respondent asked for details;[149]

(c) the experts for the respondent assumed that the knee injury was not work related because it did not occur at work;[150]

(d) the arbitrator required an unreasonable quality of evidence and unreasonably precise (and contrary to the correct test in Massih) details from the appellant of how exactly his right knee was injured;[151]

(e) the arbitrator's finding that the appellant did not disclose his previous back pain to Dr Jenkins is contrary to the facts, and the arbitrator's own finding that he did. Therefore, the inference is that the finding of the arbitrator is that the appellant did not provide sufficient information about his previous back pain. Such a finding is in error, when the appellant was not required to provide every detail and every medical record in relation to his back to Dr Jenkins. The appellant provided, he says, sufficient medical records, being those that he had at the time, and authority to Dr Jenkins to request any further medical records required;[152]

(f) the evidence showed that the appellant recovered from the pre-pallet incident back pain:[153]

(i) Dr Monks certified the appellant with full capacity for work offshore on 19 June 2019 and after a comprehensive physical examination; and

(ii) Dr Selvendra noted on 19 August 2019 that there were no impediments to full time work.

1. The appellant also asserts that the only conclusion open on the evidence was that the appellant's right knee was injured by some kind of mechanism while he was alleviating back pain in a swimming pool.[154]
2. I will deal with each of these complaints.

1. Although the appellant's particulars of Ground 3 refer to a test in four cases, his submissions do not refer to any of those cases, nor set out the 'test' the appellant contends is contained in those cases. I have therefore attempted to discern what the appellant says the correct test is, and briefly discuss it.
2. In Treasure and Lockwood-Hall McCann P referred to the authorities Leggett, Education Department of Western Australia v Morgan,[155] Cole v P & O Ports Ltd[156] and Kooragang Cement in relation to the construction of the term 'results from' and its application.
3. McCann P stated that provided the work-related injury was a material contributing cause of a period of incapacity, it could be concluded that the incapacity resulted from the compensable injury.[157]
4. In his view, it is relevant but not decisive to enquire whether the worker had fully recovered from the compensable injury, because that fact can support a finding that a later period of incapacity did not result from the injury. On the other hand, he continued, continuity of symptoms can support a finding that there was a causal connection between the injury and a period of incapacity, but that too is not an essential requirement. A period of incapacity is causally connected to a compensable injury, notwithstanding there is an interval between them, and the symptoms of the injury had settled during that interval, provided that the injury materially contributed to the incapacity. The question, therefore, is not whether the disability which caused the period of incapacity was a continuation of the work-related disability.[158]
5. It appears, in effect, that the appellant complains that the arbitrator did not apply the test as identified by McCann P when he did not accept that the respondent was required to take the appellant as it found him with his pre-existing back condition and pre-existing right knee condition and find the respondent liable for compensation where the appellant's compensable injuries aggravated or accelerated those conditions or where those conditions aggravated or accelerated the compensable injuries. This is illustrated by the arbitrator finding that the appellant's right knee condition was not aggravated by a compensable injury.
6. In oral submissions at the hearing of the appeal the appellant's counsel clarified that this ground partly concerned the rejection of Dr Jenkins' report and the acceptance by the arbitrator of the reports of Dr Dayoub and Dr Phillips.[159] That is, the arbitrator was in error when he rejected the opinion of Dr Jenkins by finding that:

(a) there was a pre-existing condition, when Dr Jenkins found that there was not; or

(b) even if there was a pre-existing condition, the pallet incident injury had resolved, such that the current incapacity was not caused by the pallet incident nor was the pallet incident injury exacerbated by the pre-existing injuries such that the current incapacity was causally connected to the pallet incident.

1. Further, the appellant said that the arbitrator made errors which lead to the wrong rejection of Dr Jenkins' opinions.[160] In summary:
   1. The arbitrator was wrong when he concluded that the appellant did not tell Dr Jenkins anything about his previous back pain history - he did.
   2. Further, the arbitrator was wrong to find the appellant minimised his history; anything more from the appellant would have been the appellant descending into making and providing to Dr Jenkins his own medical diagnosis.
   3. What the appellant told Dr Jenkins was sufficient for Dr Jenkins to have made a reliable diagnosis in any event; a medical practitioner's opinion should be based on an examination of the patient and what the practitioner sees at that point of time as the symptoms and capacity, and not other practitioners' previous assessments as to symptoms, capacity and causation.
   4. In any event, what the appellant told Dr Jenkins was correct - he had been given a clean bill of health by Dr Selvendra after consulting her in early 2019 and then he had been certified as having full capacity for work by Dr Monk shortly before his employment with the respondent. Accordingly, any finding by the arbitrator that the appellant's pre-employment position was something other than being fully fit for work was in error, and any rejection of Dr Jenkins' opinion based on such a finding is therefore also in error.
   5. In contrast, the opinions of Dr Dayoub and Dr Phillips as to the intervening act or time period within which the asserted progressive and degenerative disease has become the cause of the current incapacity are so lacking in foundational facts or precise diagnosis that they can be classed as no more as a guess. Consequently, faced with apparently competing opinions, the arbitrator was in error to prefer their opinions over the properly founded opinion of Dr Jenkins.
2. The acceptance by the arbitrator of Dr Dayoub and Dr Phillips' opinions, and the rejection of Dr Jenkins' opinion lies in the underlying information provided to each of the doctors, including past medical reports.
3. The arbitrator made a clear finding that the appellant had not fully recovered from the pre-existing condition at the time of the pallet incident, and when he applied for the position. The arbitrator was not providing his own medical opinion when making such a finding. As both the arbitrator and I have identified, the arbitrator was entitled to rely on the findings of specialist experts, particularly in technical areas.
4. The mechanism by which the arbitrator made that finding was to determine what weight was to be given to each report, as he was required to do. Faced with opinions which provided the opportunity for competing findings of fact, the arbitrator was bound to determine what weight was to be given to each competing opinion to make the required finding of fact. Findings of fact based on opinions of experts can be drawn from evidence and opinions of more than one expert and irrespective of who adduced the evidence.[161]

Did Dr Jenkins have sufficient information for the arbitrator to rely on his report and opinion?

1. In determining what weight each opinion attracted, the arbitrator was faced with doctors who had been provided with varying amounts of information. I have set out the varying information at [26], [27], [33], [34], [41], [44] of these reasons.
2. In summary, while all three doctors received some of the same information, Dr Jenkins did not receive or therefore review any medical records regarding prior complaints, injuries and investigations in relation to the appellant's back.
3. Neither was the documentation to Dr Dayoub and Dr Phillips as they have reported, challenged by the appellant.
4. Having set out his examination of the appellant and the documents and information he took into account, Dr Phillips' diagnosis was that there was long-standing degenerative changes at the lumbar spine and secondary osteoarthritis of the right knee with no objective evidence of any injury pathology to the lumbar spine. That is, there was nothing to define what could have been an injury in May 2020. Further, the imaging would be consistent with prior reports of imaging undertaken for what appears to have been a significant complaint in 2018/2019. The significance of that finding is critical in my view to the arbitrator's acceptance of Dr Phillips' report and rejection of Dr Jenkins' report. Dr Phillips has clearly made a link between what has occurred previously in relation to the appellant's back and the appellant's incapacity which he saw at the time of examination.
5. Similarly, Dr Dayoub considered both pre- and post pallet incident medical reports and information. He was not required for cross-examination and his reporting of what the appellant told him was not challenged at the arbitration hearing. His opinion was that the appellant had a pre-existing history of chronic back pain, having reported on the MRI and setting out in his first report of 4 March 2021 what, in his opinion, it revealed. That diagnosis did not change, and was confirmed once he received the called for medical reports dated prior to the pallet incident.
6. Based on that Dr Dayoub gave his opinion that the pre-existing condition continued and was no longer exacerbated or aggravated by any compensable injury.
7. Dr Jenkins did not make any finding nor comment on that possibility, and neither could he, given it appears that from neither the information given to him orally by the appellant nor any documents he received, he had any indication that there may have been anything more than, as the arbitrator recorded, a prior lower back issue resolved after one cortizone injection.
8. The arbitrator was entitled to put what weight he thought fit on each medical report. Medical reports that rely on incomplete facts cannot attract significant weight if the absence of those facts may affect the ultimate opinion.
9. Dr Jenkins' opinion being based on information which did not address any medical history prior to the pallet incident, the arbitrator was entitled to give that opinion less weight.
10. Doctor Dayoub and Dr Phillips' opinions being based on histories from both pre- and post pallet incident, the arbitrator was entitled to attribute significant weight to them, and more weight than given to Dr Jenkins' opinion.
11. The arbitrator was provided with an opinion that did not incorporate certain information and being based, he found, at least, on a minimisation of the appellant's situation, and, therefore, an unreliable factual basis. For those reasons combined, he was entitled to give no weight to Dr Jenkins' report.

Did the arbitrator expect the appellant to give the doctor his own medical diagnosis?

1. It may well have been that had Dr Jenkins been provided with all of the information available to Dr Phillips and Dr Dayoub, he may have maintained his opinion, however, the arbitrator was not given the opportunity to test that proposition. Neither can it be claimed that it was open to Dr Jenkins to call for further documents he may have required. Where he was not told by the appellant of the investigations on his back prior to the pallet incident, he would not have known to ask for them.
2. On the contrary, as the arbitrator found, the appellant, by telling Dr Jenkins that he had had a clean bill of health prior to his employment, so in mid to late 2019, actively understated the true position, being at that time on a list to see a neurosurgeon under the guidance of both Dr Selvendra and Dr Yong, having complained to those doctors prior to the pallet incident, about recurring back pain. That information would not have been descending to a diagnosis.
3. Each of the investigations performed on the appellant were facts. Even if the appellant could not be expected to specifically recall the types of investigations performed, it is clear from the list set out by Dr Dayoub and Dr Phillips and that reportedly recorded by Dr Selvendra, that prior investigations had occurred. Further, while it may not be that Dr Jenkins asked the appellant whether he had had prior investigations on his back, nevertheless, an opinion based on what is objectively known as absent historical information must weigh less than an opinion based on information including prior investigations and claims.
4. The amount of investigations, complaints of back pain, possible previous injuries to his back and suggested further investigations are not medical diagnoses - they are questions of fact, in the knowledge of the appellant.

1. It is unclear how the appellant says the arbitrator must have known, or should have known, that the appellant was not asked for details in relation to the swimming pool incident; neither is it clear how I should know that that is the case. The appellant did not refer to any indication in the arbitrator's written reasons, the transcript of the arbitration hearing or any evidence tendered, that none of the experts for the respondent asked for details.
2. In relation to the accuracy of the reporting, it could be said that in fact the appellant is correct - none of the experts for the respondent did take an accurate history, as, as the arbitrator identified, the histories summarised and reported by the respondent's medical practitioners show vague and inconsistent reporting by the appellant both to the doctors and to the arbitrator. He specifically found that he could not be satisfied that any of the histories recorded by the medical practitioners were accurate.[162]
3. In any event, the accuracy of their histories, and the consequences of inaccuracies, was not tested by the appellant at the arbitration hearing - as I have identified, none of the medical practitioners was required for cross-examination. It is therefore not possible to make a finding that the arbitrator erred in relying on the histories relied on by the medical practitioners, or misdirected himself as to how to deal with such evidence, either in using them to make findings about the appellant's credibility, or by either accepting or rejecting a medical practitioner's opinion in relation to the knee injury mechanism.

The assumption by the medical practitioners that the knee injury was not work related

1. In Exhibit 17 Dr Dayoub identified that the knee injury occurred in a friend's swimming pool. In his later report which became Exhibit 20, he called it a non-work-related injury, however, he also reported that the appellant was attempting to relieve the pressure in the lower back, knowing that the appellant had complained of low back pain after the pallet incident.
2. On its face, the knee injury is a 'non-work related injury'. There is an inference that the words 'non-work related injury' are used because the injury occurred in a friend's swimming pool, and not at work. That does not mean, reviewing Dr Dayoub's reports as a whole, that Dr Dayoub assumed that simply because the knee injury did not occur at work it was, in the context of the workers' compensation claim, not causally connected to the compensable incident.
3. Dr Dayoub was clearly aware that the claim included the right knee injury and its affect on the lower back, recording the appellant's reasons for being in the pool some six months after the pallet incident, and having been referred to the certificates of Dr Tan showing the symptoms after the pallet incident to December 2020. Therefore, while the term 'non-related work injury' may cause some confusion, it cannot be assumed that that means the doctor has automatically assumed the pool incident was non-work related, in the sense of the test of causation.
4. In any event, even if Dr Dayoub is saying that he has formed the opinion that the knee injury is not a compensable incident because it did not occur at work, Dr Dayoub's opinion in that regard is not relevant. Dr Dayoub's task was to give his opinion on whether there was a link between the ongoing incapacity and the pallet incident injury, not to label the knee injury as a work or non-work-related injury. The medical experts' task was to provide sufficient medical evidence for the arbitrator to make a finding of fact about whether the knee injury contributed in a material way to the current incapacity, and, if it did, whether the knee injury occurred in connection with the low back pain experienced by the appellant as a result of the pallet incident injury.
5. The arbitrator came to his own conclusions regarding how the appellant injured his knee, and whether that was connected to the pallet incident injury based on the medical reports, the appellant's own evidence and the arbitrator's application of the law.

Did the arbitrator expect too much precision from the appellant or Dr Jenkins?

1. The test in Massih relates to the standard of evidence required of the respondent's evidence when disentangling competing causes of incapacity. It is therefore not strictly relevant to this ground, however, I have taken it that the appellant means that he has been held to a higher standard than the respondent in providing details underlying the determinations of fact by the arbitrator.
2. That is not what has occurred. The arbitrator's findings do not reveal such a requirement of the appellant. The appellant had a legal and evidential burden to satisfy the arbitrator that his claim had merit. That included that the knee injury occurred in a particular way, and was in some way, at least, causally connected to the low back pain suffered from the pallet incident injury.
3. In assessing whether he was so satisfied, the arbitrator took into account the inconsistencies in the details provided by the appellant as to the factual mechanism within which the injury occurred. The arbitrator did not require medical explanations from the appellant himself about how his knee 'blew' or why. He rejected the appellant's contention that he was doing something because of the pain in his low back - that is, he made a factual finding. He then considered the alternate and made further findings, that is, even if the appellant was relieving his low back pain, the mechanism described by the appellant was, the arbitrator found, so far removed from the mechanism of what he was doing to relieve the pain that he could not find a causal connection between the actual mechanism of relieving the back pain and the knee injury.
4. It was not expecting too precise evidence to suggest to the appellant that if he wished to prove the required connection, his evidence should have been more particular. Dr Jenkins reported that:
   • The appellant had a clean bill of health prior to the pallet incident
   • The appellant had had low back pain since the pallet incident
   • The appellant had been in the pool to relieve that pain
   • Therefore, any injury suffered while trying to relieve that back pain resulted from the back pain
   • Given the only back pain suffered was from the pallet incident, the knee injury and any effect of that injury, was compensable.
5. As I have identified, the arbitrator rejected the 'clean bill of health' diagnosis, and therefore rejected any subsequent conclusions based on that erroneous premise. Therefore, he did not reject the contention that the right knee injury was connected to the pallet incident due to a lack of precise evidence as to how exactly his right knee was injured; he rejected it because he was not satisfied that the appellant was telling a factual truth when he said he was in the pool due to the back pain, or, in any event, if he was telling the truth, that the way in which he was alleviating the back pain could have had, as a matter of common sense, any physical impact on the knee, irrespective of how the knee injury actually occurred - either physically or medically.

Was the arbitrator wrong in finding that the appellant did not tell Dr Jenkins of his previous back pain history?

1. The appellant says that the information about the cortisone injection was information, and sufficient information, for Dr Jenkins' opinion to be reliable. However, the arbitrator found given the amount of investigation and treatment the appellant had on his back, the information about the one cortisone injection was minimising the previous back pain.
2. It is the case that the appellant told Dr Jenkins something about his back, however, that must be seen in the context of:

(a) the pallet incident injury was also to the lower back;

(b) the extensive and, as the arbitrator found it to be, relevant historical medical information obtained by Dr Dayoub and Dr Phillips; and

(c) a 'clean bill of health' being proclaimed by the appellant to Dr Jenkins in the face of outstanding scans and the apparent need for medication irrespective that there was no seen impediment for full time work.

1. Viewed in that context, a minimal mention of the low back being resolved by a cortisone injection does not reflect the factual context as the arbitrator found it to be in which the pallet injury occurred. Neither can it be said that the arbitrator erred in finding that there had been no disclosure by the appellant to Dr Jenkins, when such little information was given in that context.

Could Dr Jenkins have relied on his own examinations rather than any history given by the appellant?

1. The difficulty with this proposition is that while it is the case that Dr Jenkins could report on the symptoms as he saw them, that is not the question for determination by the arbitrator. The question for determination was whether those symptoms, or the incapacity from them, was compensable, that is, resulting from the pallet incident. That question requires more detail than simply the current symptoms, and knowledge of the pallet incident and the swimming pool incident.
2. In my view he could not have relied simply on a physical medical examination.
3. Neither should the expectation have been that Dr Jenkins could be relied on to find further information in the medical notes he may or may not have received because the appellant signed a consent. Dr Jenkins could not have known what he did not know. This is illustrated by Dr Dayoub, twice, calling for previous medical records on the suggestion that there might have been previous back pain, and not coming to a conclusion as to any link until he received them. Dr Dayoub did not expect the appellant to diagnose his own condition or capacity - he declined to provide an ultimate opinion until he was satisfied he had all relevant information, and neither should Dr Jenkins have been expected to do so.

Did the evidence show that the appellant had recovered from the pre-existing back pain by the time of the pallet incident?

1. Despite Dr Monks' certification and Dr Selvendra's declaration, the arbitrator found, and was entitled to find, that the appellant had not recovered from the pre-existing condition at the time of commencing employment and at the time of the pallet incident.
2. Dr Monks' pre-employment examination was informed by the pre-employment form the appellant completed. The arbitrator found, for the same reasons he rejected Dr Jenkins' opinions, that the appellant had given 'objectively wrong', 'wrong' or 'arguably wrong' information on the form,[163] and the answers in the form were 'neither correct nor complete'.[164] The arbitrator rejected the explanations given by the appellant in cross-examination and re-examination as to why there may be incorrect information in the form.[165]
3. Therefore, the arbitrator had grounds to reject the opinion of Dr Monks as lacking foundation. In any event, similar to the comparison of Dr Jenkins' opinion with Dr Dayoub and Dr Phillips' opinions, Dr Monks' opinion must be seen in the context of the opinions of Dr Dayoub and Dr Phillips, who determined that the appellant had not recovered from the pre-existing back pain by the time of the incident.
4. The arbitrator found that in relation to the appellant's declaration in the claim form after the pallet incident that he was 'healthy' before the incident, that his lower back was not in fact 'pain-free before the occurrence, considering [the appellant] had long standing recurrent back pain consistently reported to treating doctors from at least 21 February 2018 (Dr Sanderson) and as late as 3 December 2019 (Dr Yong)'.[166] It appears that the finding of the long-standing and repeated nature of the reports of pain lead the arbitrator to find that it would be unlikely that the appellant was 'healthy' at the time of the pre-employment check, or the pallet incident.
5. Therefore, the arbitrator was entitled to find that in the circumstances Dr Monks' certification attracted no weight.
6. While it is not suggested that information given to Dr Selvendra was incomplete, nevertheless, in the context of the claim, the arbitrator was entitled to reject a submission that the appellant had received a clean bill of health by her. Dr Selvendra suggested the appellant consult a neurosurgeon, as had, subsequently, but still before the pallet incident, Dr Yong, based on the information provided to each by the appellant.
7. In addition, and again, in the context of the medical reports of Dr Dayoub and Dr Phillips, and the weight the arbitrator was entitled to give them, those reports inform the inferences that could be drawn from Dr Selvendra's notes. One inference the arbitrator was entitled to draw is that Dr Selvendra was of the view that despite the pain, there was nothing stopping the appellant working. That does not mean Dr Selvendra found no pre-existing condition - just that if there was one, it did not stop the appellant working.
8. Therefore the arbitrator was entitled to reject a proposition that the medical evidence showed no pre-existing condition.
9. Neither was the arbitrator in error in finding that no weight could be attributed to Dr Jenkins' opinion. That led to his giving weight to the opinions of Dr Dayoub and Dr Phillips that there was a pre-existing condition. As I have identified in Ground 2, while it is the case that a pre-existing condition does not preclude compensation for a subsequent event, the arbitrator made a specific finding, based on the opinions of Dr Dayoub and Dr Phillips that while the compensable incident had aggravated the pre-existing condition, that affect no longer existed and it was the non-compensable swimming pool incident injury which was now exacerbating the pre-existing condition. As I have also identified in Ground 2, the arbitrator did not err when finding that the knee injury did not arise from a compensable incident. Neither did the arbitrator find that the presence of a pre-existing condition, even if not aggravating or accelerating that condition, automatically precluded a claim or an extension of claim. The arbitrator found that in the appellant's case, the compensable incident no longer had any connection to or bearing on the pre-existing conditions. I repeat my discussion of that test in Ground 2.
10. There being no errors of fact, the arbitrator has correctly applied the required test and considered properly the pre-existing condition of the appellant. While leave can be granted because there is a question of law, there is no error of law, or jurisdictional error, and the complaints about the expectations of the arbitrator on the appellant's information and evidence have no basis, and Ground 3 fails.

1. The appellant's primary contention in this ground is that the arbitrator failed to apply the correct test in relation to the presumption of incapacity. The correct test, says the appellant, comes from R v Hill.[167] The failure to apply that test was brought about by the arbitrator's failure to consider the appellant's evidence to find suitable employment, leading to a failure to consider that the failure to obtain suitable employment was because of the compensable injury or that he was not qualified.
2. Accordingly, the arbitrator erred when he found, as he did in [147] of his reasons, that the compensable lower back injury had ceased by 14 December 2022, and that the respondent was not liable to pay for the medical expenses in relation to the non-compensable condition of chronic low back pain.
3. The failure to apply the correct test is illustrated by the fact that the arbitrator, despite being referred to it, did not mention Hill in his reasons for decision, despite the appellant referring to them in submissions.
4. A contention that the arbitrator failed to consider evidence in relation to finding suitable employment is predicated on the basis that the arbitrator was required to move to a determination of the employee's financial liability. The arbitrator was only required to move to that determination if the arbitrator found that the current incapacity resulted from a compensable incident.
5. Under s 217 of the former Act, where the arbitrator has found that an injury to a worker is compensable and has resulted in total incapacity for work, under s 217(2) the arbitrator may make an order as to total liability of the employer for the incapacity. In doing so, under s 217(3), the arbitrator must consider the social and financial circumstances and the reasonable financial needs of the worker.
6. It is when determining the need for that payment under s 217(3) that the worker's attempts to find suitable employment becomes relevant. In the present case the arbitrator did not reach that point, having determined that there was no incapacity from a compensable incident.
7. In effect, this is another attack against the arbitrator's findings that the current incapacity is not caused by the pallet incident.
8. While the appellant neither made reference to the paragraph number nor expanded on his description of the 'presumption of continuity' referred to in this ground either in the ground itself or his written or oral submissions, I have assumed that the appellant is referring to the words of Nield AJ in delivering his verdict in the matter of Hill, a criminal prosecution. In Hill his Honour said that the presumption of continuance,[168]

... is that if a fact is proved to exist at a particular time then, in certain circumstances, it will be presumed to have existed at an earlier time or at a later time. It is nothing more than a convenient way of describing a process of logic or reasoning involving the drawing of inferences from proved facts.

1. The appellant by his ground appears to be complaining that the arbitrator erred by not finding that there was a continuous incapacity from the compensable incident.
2. In his written submissions the appellant's complaint is that the arbitrator having made a 'fundamental error that the causal chain had been snapped',[169] he did not consider any of the appellant's evidence of finding suitable employment. I have found that Grounds 1 - 3 have no merit, that is, the arbitrator did not err either in fact or law in coming to the conclusions he did in relation to the connection between the current incapacity and the compensable incident.
3. Even considering Nield JA's suggestion of the way in which a continuation of circumstances may be dealt with in coming to a determination in relation to a fact, I remain of the view that the arbitrator's reasoning in relation to his acceptance and rejection of particular parts of the evidence does not disclose error. While it may be that a presumption can be made that facts and factual circumstances continue, it is also the case that that presumption can be displaced by accepted evidence of a break in that continuum. That is precisely what the arbitrator found in the present case, that is, that in the time since the compensable pallet incident the appellant had recovered at least by 14 December 2022.
4. Having found he recovered, there was no need for the arbitrator to consider the appellant's efforts to find employment. In any event, the appellant's claim failed because he failed to satisfy the arbitrator that the pallet incident caused his current incapacity, not because he had not sought suitable employment.

1. In his written submissions in relation to Ground 4, the appellant also addressed the findings of the arbitrator on the appellant's credibility. Specifically, the appellant says that:

(a) the appellant's credibility in relation to his pre-employment medical examination is irrelevant to answering the ultimate question of whether there is a permanent and total incapacity resulting from a compensable injury and whether his social and financial circumstances justify an extension to the prescribed amount;

(b) the appellant answered the questions in his pre-employment medical examination and his claim form and questions asked by medical practitioners according to definitions of words as he believed them to be. He responded to questions guiding him on the level of detail required and the appellant is a simple man who continues to be confused by the workers' compensation system;

(c) the appellant disclosed his various symptoms at various points in time to various medical practitioners and those practitioners certified the appellant with the appropriate level of incapacity; and

(d) the learned arbitrator correctly finding that the applicant's certification as to his incapacity was accurate at various points in time, that is the evidence that is relevant to the ultimate question, not whether the appellant ticked yes or no to questions on a pre-employment medical questionnaire.

1. While not a specific ground, it appears that contention is discussed in this ground as it is the underlying reason why, the appellant says, the arbitrator has erred - by failing to make findings such that he could move to the determination of liability, that failure being occasioned by a wrong determination of the appellant's credibility, leading to a wrong determination of a continuing incapacity. Accordingly, I will discuss this contention here.
2. The arbitrator identified that the appellant's credibility was central to the determination of many of the issues.[170] That was because his case heavily relied on the evidence he gave on many topics at the arbitration hearing and the history he gave to the expert witnesses.[171] While the arbitrator identified the need for the information provided by the appellant to the medical witnesses to be truthful, accurate and reliable, it is the case that for the arbitrator to accept the appellant's evidence at all, it must also be truthful, accurate and reliable.
3. In the case of a finding that is based, at least to a substantial degree, on an assessment of the credibility of one or more witnesses, an appellate court will not interfere with the finding unless it is demonstrated to be wrong by reference to incontrovertible facts or uncontested testimony, or because the finding is glaringly improbable or contrary to compelling inferences, because the primary finder of fact failed to use, or has palpably misused, their advantage as the primary finder of fact.[172]
4. It is generally accepted that when the finder of fact needs to make findings of credibility, it is necessary to assess the credibility and reliability of the evidence of the witness and thereby determine the weight to be given to the witness' evidence. Determining credibility is an assessment of the honesty of the witness. Determining reliability, is an assessment of whether the witness has given an accurate account of what happened. A witness may be honest but not reliable due to factors such as circumstances affecting memory.
5. The fact finder may take into account the consistency of a witness' utterances on different occasions and whether the witness' testimony is consistent and, if there are inconsistencies, whether the inconsistencies are in respect of significant matters and determine if there is any reasonable explanation for the inconsistencies. The fact finder may consider whether the evidence of a witness is consistent with the evidence of other witnesses whose evidence they have accepted. If a witness' evidence is inconsistent, that is a factor that can be taken into account in assessing the evidence of that witness. If the evidence given by a witness has been consistent on significant matters, that may be a factor that supports determination that the witness is telling the truth.
6. The fact finder may have regard to the demeanour of each of the witnesses in assessing their evidence, mindful that some witnesses, understandably, may feel apprehensive when giving evidence in a courtroom, that cross-examination is stressful and that a witness might use language that is imprecise and that these factors may affect the witness' demeanour and therefore, should not necessarily reflect on their credibility.
7. In assessing the appellant's credibility, the arbitrator also took into account that clinical records are written in the course of a busy practice where the clinician is primarily there to observe and administer treatment, and they should not be construed with the minute attention one might give a formal legal document.[173]
8. In assessing the appellant's credibility in relation to crucial parts of his claim, the arbitrator compared the clinical notes, in that context just set out, with the explanations for inconsistencies given by the appellant in cross-examination,[174] the lack of candour to doctors about past medical history, his findings that the appellant's account of some things was just 'plainly wrong'[175] and the appellant's demeanour, being affable to commence with, however that affability receding on occasions when he was challenged about inconsistencies and lack of candour in cross-examination, becoming combative and refusing to accept basic propositions.[176]
9. In making those assessments, the arbitrator therefore listened to the cross-examination and the explanations given, particularly in relation to the histories given to the medical professionals, and the information provided on the pre-employment form, and rejected the appellant's evidence almost in its entirety. He gave detailed reasons as to why he did so.
10. In assessing the appellant's credibility, the arbitrator was entitled to take into account all the evidence before him, irrespective of its factual relevance to any particular point of claim. That is, although the pre-employment medical examination may not factually be relevant to the ultimate question of whether the appellant is permanently and totally incapacitated resulting from a compensable injury, the arbitrator was entitled to view the manner in which the appellant completed that form, and the reasons he gave for inconsistencies within it, as relevant to the overall finding of the appellant's credibility on questions required for his determination. The arbitrator heard the appellant's reasons as to why that document may appear inconsistent with other information, as well as explanations as to other inconsistencies in medical history as is reported by the medical professionals, and rejected those explanations, as, being the finder of fact, he was entitled to do. Whether the appellant gave more or less detail depending on how much detail was asked of him, was also rejected by the arbitrator.
11. Therefore, whether the appellant correctly disclosed information to medical professionals or not, the arbitrator was entitled to make findings of credibility in relation to the appellant which led to the basis for findings as to his claim in general. Having weighed up all the evidence, he made the findings that I have set out.
12. As the respondent pointed out at the hearing of this appeal, the arbitrator made findings of fact in relation to the credibility of the appellant which cannot be challenged in this appeal. In any event, in so far as any findings of credibility which have led to the application of the facts to the law, and thus revealing error, may have occurred, I am not of the view that the appellant has demonstrated that the arbitrator made a wrong reference to incontrovertible facts or uncontested testimony or made a finding that is glaringly improbable or contrary to compelling inferences or a failure to use, or to palpably misuse, his advantage as the adjudicator at first instance. The arbitrator, as I have set out, referred at length to the various documentary evidence he preferred over the appellant's testimony and set out in detail the inconsistencies he found in the evidence. A review of those findings does not reveal any such error.
13. Accordingly, while leave can be granted because this ground involves a question of law, as far as the complaint is in relation to the application of a 'presumption of continuity' there is no error. As far as this ground alleges an error in relation to the findings on credibility, or the application of those findings, the ground fails, and therefore Ground 4 fails.

1. The appellant's primary contention in this ground is that:

(a) s 79 of the former Act was not enlivened, or, if it was,

(b) the arbitrator failed to apply the correct tests in Re Iliadis v Comcare,[177] Re Schofield v Comcare[178] and Anderson v Mineral By-Products Pty Ltd.[179]

1. Section 79 of the former Act was as follows:
   1. Wilful and false representation by worker

Where it is proved that the worker has, at the time of seeking or entering employment in respect of which he claims compensation for an injury, wilfully and falsely represented himself as not having previously suffered from the injury an arbitrator may in the arbitrator's discretion refuse to award compensation which otherwise would be payable.

1. Having found that the appellant's incapacity did not arise from a compensable incident, s 79 was not applicable as there was consequently no compensation 'otherwise payable'. However, the arbitrator addressed the application of s 79 in case he was in error in relation to his findings of fact about whether there was an incapacity resulting from a compensable incident.
2. I have already determined that the arbitrator did not make errors of fact, nor apply the incorrect tests in concluding that the incapacity was not the result of the compensable incident. Therefore, he did not err in finding that there was no compensation payable irrespective of the application of s 79.
3. However, having moved to consider in perhaps a precautionary manner the application of s 79, should he be wrong about the causal connection between the pallet incident and the ongoing incapacity, he relied on his findings of fact as to the appellant's truthfulness in the pre-employment form to determine whether s 79 was enlivened.
4. From the ground as drafted and its particulars, the appellant appears to complain that the arbitrator erred in:

(a) finding that the appellant at the time of entering into or seeking employment in respect of which he claims compensation wilfully and falsely represented himself as not having previously suffered from the injury;

(b) applying his discretion, if the discretion was enlivened, by ignoring the relevant 'tests'; and

(c) payments having already been made to the appellant showing an acceptance of the compensable injury, finding that he was not precluded from exercising his discretion.

1. The first complaint is an alleged error in the finding that the appellant wilfully and falsely represented himself. The complaint is that even if there was a pre-existing injury, the arbitrator erred in finding that the injury causing the incapacity was the pre-existing injury - that is, the injury claimed for is not the injury previously suffered from, and s 79 was not enlivened.

Was the representation in relation to 'the' injury?

1. The appellant says that the arbitrator cannot have been satisfied that the appellant had previously suffered from the injury, because the pallet injury is a different injury to any previous injury the appellant may have suffered. For example,

(a) the arbitrator failed to consider a finding in a report of Dr Selvendra that the injury was to the opposite side of the appellant's back to the pre-existing pain, the doctor finding that in 2019 the pain in the lower back was on the right side, however, when presenting after the pallet incident the appellant was tender over his left lower back, meaning, according to the appellant, that the inference is that the appellant sustained a new left lower back injury on 22 May 2022; and

(b) Dr Kumar, three days after the pallet incident, had noted no neural compromise on the right side identified to explain the symptoms, which he had noted came from 'moving pallets at work on Friday, hurt his back woke up Saturday and was in pain still' and there is potential for compromise of left L4 at the far lateral location.

1. I have set out at [19] - [50] of these reasons the arbitrator's findings on the medical evidence. While he may not have referred to the reports or notes of Dr Selvendra or Dr Kumar in his findings, it is clear from his reasons that he placed significant weight on the opinions of Dr Dayoub and Dr Phillips, who both had Dr Selvendra and Dr Kumar's notes. Doctor Dayoub and Dr Phillips found that the pallet incident exacerbated an existing condition, and did not create a new and separate injury.
2. The arbitrator was entitled to rely on the opinions of doctors who had considered the medical evidence as to the nature and mechanism of the pre-existing condition. Failure to refer to these, and attribute them separate weight, was not an error in those circumstances.
3. I have set out at [19], [74] - [75] of these reasons the arbitrator's findings on the pre-employment form. I have also set out at [238] of these reasons the circumstances on which findings of credibility may be set aside. For the reasons I have expressed in [245] and [247] in relation to Ground 4 I am satisfied that there is no reason to set aside the findings of the arbitrator in relation to the filling in of the pre-employment form, that is, there was, on the face of the answer, a wilful and false representation about previous back injury.
4. The arbitrator did not err in his application of the facts, as he found them to be, in determining whether the prior injury was the injury claimed for in determining whether the discretion in s 79 was enlivened.

If enlivened, did the arbitrator apply the correct tests?

1. The appellant's second complaint is that the representation was a representation in the context of the words 'seeking or entering employment in respect of which he claims compensation'. The appellant says that he was not seeking or entering employment as a person who lifts pallets, and the arbitrator could and should have found that the representation that there was no previous back condition was not a wilful and false representation in the context of the employment he was seeking, and therefore the representation should have been given no weight in the exercise of the discretion.
2. In particular:

(a) there was no evidence that had the respondent known of the appellant's previous back and right knee injury that it would not have employed the appellant;

(b) the arbitrator failed to consider medical certification, by Dr Monk, a practitioner chosen by the respondent, that the appellant was fit for work as an offshore field technician, where the respondent failed to put to that practitioner past medical records, drawing an available 'Jones v Dunkel' inference;

(c) the arbitrator failed to consider the appellant's full capacity to work as an offshore field technician until he was instructed to lift the pallets, an operation other workers had refused to undertake, being outside their usual duties;

(d) Dr Selvendra found in August 2019 that there were no symptoms to affect full time work; and

(e) the arbitrator overlooked the applicant's evidence that moving pallets was not in his usual duties and that he had been instructed to do so as the respondent was moving premises and did not want to hire professional movers, in other words, moving heavy pallets was neither an inherent requirement for what the respondent employed the appellant for and nor did Dr Monks certify the appellant for moving pallets after the pre-employment medical examination.

1. That the arbitrator so erred is illustrated by his neither referring to the relevant cases, despite the appellant referring to them in submissions, nor the report of Dr Selvendra. The appellant names three cases, and suggests there is a test to be discerned from each in the application of the discretion, without describing in submissions what the test is.
2. If s 79 of the former Act was enlivened, then it involves a discretion. Before the arbitrator's decision in relation to the application of his discretion can be reviewed in relation to the application of s 79 of the former Act, it must appear that some error has been made in exercising the discretion, such as acting on a wrong principle, allowing extraneous or irrelevant matters to guide or affect him, mistaking the facts or failing to take into account some material consideration. Alternatively, if it appears upon the facts that it is unreasonable or plainly unjust, the appellate court may infer that in some way there has been a failure to properly exercise the discretion even though the error may not be discoverable.[180]
3. I am unable to find such error.

1. Schofield and Iliadis relate to Commonwealth legislation - s 7(7) of the Safety, Rehabilitation and Compensation Act 1988 (Cth). It is drafted differently to s 79, in that it does not appear to provide a discretion - once a representation about a prior disease or injury is found to be wilful and false, that disease 'shall not' be taken to be a disease or injury for the purposes of the Act. Any review of those cases must be done in that context.
2. In Schofield, the worker had been exposed to chemicals in his first employment, causing headaches, skin rashes and change in mood and behaviour, among other effects, requiring ongoing medical intervention, with days absent from work, resulting in workers' compensation payments. He issued a writ against the first employer outlining significant and ongoing injuries. He then took on, briefly, further employment where he later reported sunstroke.
3. However, in applying for a subsequent position similar to the first, he answered no to questions in relation to sunstroke, dermatitis or skin eruption, recent medical treatment and the only 'accident or surgical treatment' received as being tonsils and appendix removal. He later answered 'no' to a further questionnaire regarding headaches, anxiety, fatigue, dermatitis, eczema 'or any other skin rash', that he was not aware of any health issues that would interfere with his work, and that he was not and had never received workers' or employees' compensation.
4. The Administrative Appeals Tribunal member found that the answers were deliberately false to avoid giving any information which might have prejudiced the worker's chances of obtaining the subsequent employment. Section 7(7) of the Act applied and compensation was denied.
5. The member found that 'the applicant deliberately avoided giving any information which might have prejudiced his chances of obtaining employment'[181] in my view to set out the motive with which the Member has been able to make a finding as the wilfulness of the representations.
6. In Iliades the worker had had back pain prior to her employment, however had no idea that she was suffering a degenerative condition. She maintained her work, and her evidence, which the tribunal member accepted as being credible, was that while her back had been sore from time to time it was nothing a person who worked hard as a cleaner would not experience.
7. In determining whether the worker's representation in pre-employment forms that she did not suffer from any back ailment or disease was wilful and false, the member reviewed some Commonwealth cases and determined that 'wilful' was considered as incorporating a degree of blameworthiness, 'particularly in the light of any motivation for the making of a false statement'.[182] Accordingly, the member found the symptoms the worker failed to disclose cannot be regarded as a false representation under s 7(7) unless 'the false representation related to a disease or an ailment, which if the word "wilful" is to have any meaning, she knew she had, and as to which she intentionally failed to disclose'.[183]
8. In contrast, in Anderson the worker twice hurt the same elbow, at different employment. When being assessed for the second employment, the worker:

(a) did not mention in any pre-employment intake that he was still employed by the first employer, albeit on leave for the injury;

(b) did not mention being in receipt at that time of compensation payments;

(c) said 'no' to questions on forms about ever having had trouble with elbows or wrists, or having ever been in an industrial accident, and

(d) despite telling the pre-employment medical check doctor that he did have a sore arm, he said it was alright at that time, due to a recent cortisone injection.

1. The Workers' Compensation Board found it 'irresistible', despite the admission to the doctor, that the worker had wilfully and falsely represented himself as not having previously suffered from the disability. Despite that finding, the Board also concluded that the worker had not intended to prejudice the second employer by the misrepresentation; that is, in making the misrepresentation, the Board were able to make a finding that the worker believed that he would be able to undertake his employment. Given the finding of wilfulness and falsity, the Board considered the discretion in s 79 enlivened.
2. The Board then assessed whether the worker should be barred from compensation it had found was otherwise due. Finding that the worker had not intended to prejudice the subsequent employer, evinced a desire to remain in the workforce and was hopeful he would be able to discharge his duties, which he might have realised had the second incident not occurred, the Board declined to exercise its discretion to refuse to award the compensation otherwise due.
3. From those three cases, it is accepted that the motive of the worker, and any intended potential prejudice to the employer are relevant factors in the exercise of the discretion. However, these cases could not be said to evince a 'test'. That is because:

(a) the Commonwealth cases can only give guidance, as I have explained, given their different regime and the West Australian case is but one case at the level of the Board; and

(b) there are many factors relevant to the exercise of a discretion, and therefore the finality of a 'test' is not applicable in such a determination.

1. At best, therefore, these cases may be of assistance in a determination of the weight to be given to this factor. The appellant argues that in this case, because the pallet incident did not involve the work for which the appellant was employed, it was not open to find that there was no deliberate concealment of the injury such that it would, or was intended to, prejudice the employer.
2. However, given it is only one relevant factor, and the weight to be given that factor is at the discretion of the tribunal, even a genuine belief by the worker that they may still have capacity to complete the new employment, with no prejudice to the employer, may not necessarily lead the tribunal to a finding that compensation should nevertheless be awarded.

1. While relevant to the question of whether the discretion is enlivened, in my view s 79 does not preclude an assessment of the method and frequency of the representations, and the reasons given by the worker for them in determining whether the discretion should be exercised, once enlivened.
2. The arbitrator considered the questions on the pre-employment form, and the appellant's answers.[184] The questions were not limited to backache, they involved hospitalisation, surgery, other injuries and work-related injuries, to all of which the arbitrator found the answers given by the appellant were wrong or arguably wrong. Neither did he tell the truth, he found, in evidence when the appellant said he did not have help in completing the form.
3. The arbitrator:

(a) determined that the incorrect answers were deliberate;[185] and

(b) rejected the appellant's evidence that while not on the form, he did tell Dr Monks of the previous surgeries to his knees.[186]

1. The arbitrator also considered the appellant's answers in relation to other aspects of his claim:

(a) in relation to the claim form for the current compensation, he found that his answer 'yes' to the question about whether the area injured was previously healthy was incorrect,[187] even if the appellant thought that it simply meant 'was it pain free?';[188]

(b) in relation to his answers in cross-examination regarding the previous claims for his lower back, finding that his denials of the claim were wrong, eroding his reliability (and therefore credibility) as a witness;[189] and

(c) the varying and limited information he gave to the doctors in relation to the hearing, as I have set out in relation to the other grounds.

1. The arbitrator found that the falsification on the pre-employment form weighed against the appellant as it was a condition suffered at the very time of his pre-employment check, and for which he was continuing to receive treatment. He said, 'In other words, this was not some ancient recovered condition that was not disclosed'[190] and that was a deliberate concealment in the pre-employment medical assessment.
2. While the arbitrator did not report that he had weighed that factor with the fact that the lifting of pallets was not what would be encompassed in the employment as a field technician, it can be inferred that he was cognisant of the purpose of the medical form and the answers the appellant gave.
3. The arbitrator was entitled to give significant weight to the deliberate falsity, given not only was it on the pre-employment form, but encompassed what the arbitrator found he did not tell Dr Monks, and his continued minimisation of his pre-existing and ongoing condition in his compensation claim form, to the medical experts engaged to report for the purposes of his claim and at the hearing.
4. His conclusion was that the appellant 'deliberately concealed this condition from [the respondent] in the pre-employment medical assessment'.[191] Given that deliberate concealment, this was not, he must have found, a misunderstanding of the significance of the prior condition, or a misunderstanding of its impact on his employment, as it was to be, or made in the genuine belief that he could maintain his employment without incident, even though medical assessment at that time suggested that he may be able to.
5. An inference may have been drawn from the evidence that the appellant was hopeful, given the opinions of Dr Selvendra and Dr Monks, and the different employment to lifting pallets, that he would be able to discharge his duties with the respondent, and that might have occurred but for the pallet incident. There also was no evidence that the respondent would not have employed the appellant had they known of the condition.
6. However, in relation to Dr Monks, as with Dr Jenkins, the arbitrator found that the underlying information given to Dr Monks was incorrect[192] and therefore his opinion was unreliable.[193]
7. Dr Selvendra's opinion did not suffer from the same underlying inadequacies. However, despite that, and even without any evidence from the respondent about whether they would have nevertheless employed the appellant, given his findings about the continuing deliberate nature of the appellant's minimisation of his pre-existing condition and claims, the arbitrator was entitled to give Dr Selvendra's opinion, and any question of whether he still would have been employed, less weight.
8. The arbitrator has made a finding that the falsity was deliberately targeted at concealing his condition from his employer in general. That is, it appears from the arbitrator's reasoning that the wilfulness and falsity was so wide ranging and prejudicial that it reflected on any task the appellant was asked to perform. On an overall reading of the arbitrator's reasons it was at all times accepted by him that the lifting of the pallets was part of the appellant's employment, it having occurred in the course of his employment.
9. In assessing the breadth and detail of the appellant's wilfulness and falsity, and continued minimisation, the arbitrator was entitled to have come to the view that the intention of the appellant was to hide the current condition from his employer for all and any purposes.
10. I am therefore satisfied that it was open to the arbitrator to attribute weight to the breadth of the appellant's wilful and false representations on the pre-employment form, and his continuing minimisation and incorrect answers in other forum in determining whether he should refuse to award compensation, had it have been found payable, irrespective of whether the lifting of the pallets may have been outside the expected duties of the appellant.
11. There was therefore no error in the application of s 79.

Was the arbitrator precluded from making a finding under s 79, given the payments already made?

1. The appellant has set out 13 particulars of this ground. The first set of particulars[194] relates to the apparent complaint that the arbitrator was effectively precluded from determining that compensation cannot be payable because compensation had already been paid until the prescribed amount was exhausted in July 2022, the arbitrator making no specific finding that compensation was not payable during that time.
2. I am not satisfied that in the context of the arbitrator having found there were no compensation or expenses payable for the knee injury or any caused incapacity from the back condition, his determination under s 79 was required to consider, effectively, whether he was precluded from determining that those expenses and compensation, and the total liability claimed, were otherwise not payable.
3. The arbitrator addressed s 79 unnecessarily, other than to address the issue because it had been raised in argument. It appears his primary consideration was the affect of the appellant's declarations in the pre-employment form being wilful and false, and their consequences. Were the discretion under s 79 a live issue, a determination of the consideration of the issue of payments having already being made may be important, however, as I have found that the arbitrator did not err in finding that there was no compensation payable, whether the previous payments made preclude a decision under s 79 of the former Act is not a necessary finding I must make for the success or otherwise of this appeal.
4. The appellant has not shown error, and Ground 5 fails.

1. For all these reasons the appeal should be dismissed. I will hear from the parties as to costs.

I certify that the preceding paragraph(s) comprise the reasons for decision of the District Court of Western Australia.

[1] Arbitrator's reasons for decision (ARD) [4].

[2] ARD [5] - [33] with his conclusions at [34] - [37].

[13] ARD [15], [60] - [62], [70].

[68] Leggett v Argyle Diamond Mines Pty Ltd [2000] WASCA 182.

[69] Napier v BHP Billiton (Worsley Alumina) Pty Ltd [2015] WASCA 230; (2015) 49 WAR 243 (Napier).

[84] BHP Billiton Iron Ore Pty Ltd v Treby [2017] WADC 6 [34] citing Minister for Immigration and Citizenship v SZMDS [2010] HCA 16; (2010) 240 CLR 611 [123] - [127], [130].

[85] BHP Billiton Iron Ore Pty Ltd v Treby [2017] WADC 6 [36] - [40] citing Minister for Immigration and Citizenship v Li [2013] HCA 18; (2013) 249 CLR 332 [22] - [30].

[86] Wilson v Bentley Health Service (Unreported, WACC, C31-2007, 6 July 2007) (McCann P).

[87] As clarified at the Appeal hearing ts 7.

[93] Napier v BHP Billiton (Worsley Alumina) Pty Ltd [2015] WASCA 230; (2015) 49 WAR 243.

[94] See also Ward v Corrimal-Balgownie Collieries Ltd [1938] HCA 70; (1938) 61 CLR 120, 129.

[95] Kooragang Cement Pty Ltd v Bates (1994) 35 NSWLR 452.

[96] Wilson v Bentley Health Service (Unreported, WACC, C31-2007, 6 July 2007) [9(iii)], [17] (McCann P), citing Kooragang Cement Pty Ltd v Bates (1994) 35 NSWLR 452, 464.

[97] Wilson v Bentley Health Service (Unreported, WACC, C31-2007, 6 July 2007) [9(iv)], [17] (McCann P), citing Leggett v Argyle Diamond Mines Pty Ltd [2000] WASCA 182 [24].

[98] Wilson v Bentley Health Service (Unreported, WACC, C31-2007, 6 July 2007) [17], [18] (McCann P).

[99] Wilson v Bentley Health Service (Unreported, WACC, C31-2007, 6 July 2007) [23] (McCann P).

[100] Wilson v Bentley Health Service (Unreported, WACC, C31-2007, 6 July 2007) [23] (McCann P).

[107] Massih v Electricity Networks Corporation t/as Western Power [2016] WADC 146.

[108] Respondent's written submissions 26 August 2024, par 27.

[110] Appellant's written submissions 8 August 2024, par 26.

[111] Massih v Electricity Networks Corporation t/as Western Power [2016] WADC 146 [71].

[112] Massih v Electricity Networks Corporation t/as Western Power [2016] WADC 146 [72].

[113] Massih v Electricity Networks Corporation t/as Western Power [2016] WADC 146 [69], [70] citing Watts v Rake [1960] HCA 58; (1960) 108 CLR 158, 159 - 160 and Purkess v Crittenden [1965] HCA 34; (1965) 114 CLR 164, 168.

[114] Purkess v Crittenden [1965] HCA 34; (1965) 114 CLR 164 (168).

[115] Massih v Electricity Networks Corporation t/as Western Power [2016] WADC 146 [70] citing Purkess v Crittenden [1965] HCA 34; (1965) 114 CLR 164, 168 and 170.

[128] See Purkess v Crittenden [1965] HCA 34; (1965) 114 CLR 164, 168.

[129] Appellant's written submissions, 8 August 2024, par 28.

[130] Appellant's written submissions, 8 August 2024, par 30.

[136] Minister for Education v Shire of Northam [2016] WADC 42.

[137] ARD [84] citing Minister for Education v Shire of Northam [2016] WADC 42 [28], [31].

[138] Minister for Education v Shire of Northam [2016] WADC 42 [31], [32].

[139] ARD [8] - [80], [86] - [102].

[146] Treasure v WA Country Health Service (Unreported, WACC, C17-2010, 26 November 2010) (McCann P).

[147] Lockwood-Hall v BHP Billiton Nickel West Pty Ltd (Unreported, WACC, C5-2012, 18 May 2012) (McCann P).

[155] Education Department of Western Australia v Morgan [2000] WASCA 291.

[156] Cole v P & O Ports Ltd [2002] WASCA 157.

[157] Treasure v WA Country Health Service (Unreported, WACC, C17-2010, 26 November 2010) [5] (McCann P).

[158] Treasure v WA Country Health Service (Unreported, WACC, C17-2010, 26 November 2010) [7] (McCann P).

[161] Minister for Education v Shire of Northam [2016] WADC 42 [30].

[167] R v Hill [2012] ACTSC 121.

[168] R v Hill [2012] ACTSC 121 [27].

[169] Appellant's written submissions, 8 August 2024, par 49.

[172] Smart v Power [2019] WASCA 106 [103].

[177] Re Iliadis v Comcare (1996) 41 ALD 576.

[178] Re Schofield v Comcare [1995] AATA 42; (1995) 38 ALD 124.

[179] Anderson v Mineral By-Products Pty Ltd (1987) 8 WCR (WA) 37.

[180] D'Orsogna Ltd v Zhang [2019] WADC 73 [68].

[181] Re Schofield v Comcare [1995] AATA 42; (1995) 38 ALD 124 [30].

[182] Re Iliadis v Comcare (1996) 41 ALD 576 [31].

[183] Re Iliadis v Comcare (1996) 41 ALD 576 [32].

[184] ARD [9(a)] - [9(c)], [10].