Jurisdiction : WORKERS' COMPENSATION ARBITRATION SERVICE (WA)

Workers' compensation - Appeal - Section 61(1) notice by employer to discontinue weekly payments - Section 61(3) application by worker disputing right of employer to discontinue weekly payments - Whether arbitrator limited to deciding whether payments should be discontinued as worker's incapacity no longer a result of the work injury - Whether arbitrator erred in not deciding extent of worker's current incapacity and whether he had a partial capacity to work - Whether arbitrator erred in decision which party carried the onus to prove that the worker's incapacity was still caused by the work injury - Whether the arbitrator failed to provide adequate reasons for her decision

Workers' Compensation and Injury Management Act 1981(WA) s 61(1), s 61(3), s 213(4)

Australian Broadcasting Tribunal v Bond [1990] HCA 33; (1990) 170 CLR 321

Beale v Government Insurance Office (NSW) (1997) 48 NSWLR 430

BHP Billiton Iron Ore Pty Ltd v Brady [2008] WASCA 250

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

Collector of Customs v Agfa-Gevaert Ltd [1996] HCA 36; (1996) 186 CLR 389

Compass Group (Australia) Pty Ltd v Delides [2009] WACC C1-2009

Cord Nominees Pty Ltd T/as Hardchrome Sales v Gomes (Unreported, WASCA, Library No 8520, 28 September 1990)

Denken Pty Ltd v Judith Footer (Unreported, CM-236/01 (Hogan PM) 29 August 2002)

Glenn-Craig Villages Pty Ltd v Donaghy (1992) 7 WAR 122

Hayes v Federal Commissioner of Taxation [1956] HCA 21; (1956) 96 CLR 47

Heat Containment Industries v Kimberley (1990) 2 WAR 47

Jupero Pty Ltd v Karl Finnis (Unreported CM-6/00 (Packington J) 20 June 2000)

Kanowna Belle Goldmines v Feierabend [2003] WASCA 246

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

Lodkowski v Comcare (1998) 53 ALD 371

Manonai v Burns [2011] WASCA 165

Margaret Roney v Accommodation West Pty Ltd [2009] WACC C10-2009

Mayne Nickless Ltd t/as Wards Express v Mayne (Unreported, WASCA, Library No 960736, 19 December 1996)

Minister for Immigration and Ethnic Affairs v Wu Shan Liang [1996] HCA 6; (1996) 185 CLR 259

Mitchell v Canal Rocks Beach Resort [2002] WASCA 331

Mount Lawley Pty Ltd v Planning Commission (WA) [2004] WASCA 149; (2004) 29 WAR 273

Pacific Industrial Co v Jakovljevic [2008] WASCA 60

Peter Nardi v Department of Education and Training [2006] WACC C22-2006

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

Qantas Flight Catering v Joncevski [2004] WASCA 121

Secretary to the Department of Premier and Cabinet [1999] VSCA 117; [1999] 3 VR 331

SNF (Australia) Pty Ltd v Jones [2008] WASCA 121

Sotico Pty Ltd v Wilson [2007] WASCA 112

Summit Homes v Lucev (1996) 16 WAR 566

Velez Pty Ltd v Tudor [2011] WASCA 218

Vurlow v Leighton Nursing Home [1978] WAR 15

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 [2007] WACC C31-2007

1 SCHOOMBEE DCJ: This matter concerns an appeal by Mirrabooka/Nollamara Car Transport, the employer, against a decision by the Workers' Compensation Arbitration Service delivered on 21 September 2015 pursuant to which the arbitrator ordered that the weekly payments of compensation made to Mr Rintoul, the worker, should not be discontinued.

2 Mr Rintoul is a 50-year-old truck driver who suffered an injury to his neck and back after he fell from a truck trailer while loading vehicles during the course of his employment on 14 October 2013. The insurer for Mirrabooka/Nollamara Car Transport accepted workers' compensation liability for the injury and made ongoing weekly payments to Mr Rintoul.

3 On 6 October 2014 Mr Rintoul was served with a notice pursuant to s 61(1) of the Workers' Compensation and Injury Management Act 1981 (the Act) advising him of his employer's intention to discontinue his weekly payments of compensation. The notice stated that it was based upon the medical reports of Dr Phillip Meyerkort, dated 30 May 2014 and 24 September 2014, attached to the notice, and that Mr Rintoul's incapacity was no longer a result of the injury that he had sustained at work.

4 In response, Mr Rintoul applied under s 61(3) for an order of an arbitrator that the weekly payments should not be discontinued. The matter was referred to conciliation under the Act, but the parties were unable to reach an agreement.

5 The s 61(3) application was heard by the arbitrator on 18 June 2015. The arbitrator came to the conclusion that Mr Rintoul's incapacity continued to result, at least materially, from the work injury and that the weekly payments of compensation should not be discontinued. She rejected the argument by counsel for Mirrabooka/Nollamara Car Transport that on bringing the application under s 61(3) Mr Rintoul had a burden to prove, not only an ongoing incapacity to work and that this resulted from the work injury, but also the exact level of his incapacity and to what extent he was capable of performing restricted duties and earning some income, albeit at a lesser level than prior to the accident.

6 The arbitrator essentially held that she was only required to decide the issue raised in the s 61(1) notice, namely whether the weekly payments should be discontinued because Mr Rintoul's current incapacity was no longer a result of the work injury. She came to the conclusion that in the absence of the s 61(1) notice being based, in the alternative, on the intention of the employer to reduce the weekly payments, she was not required or entitled to deal with the question whether Mr Rintoul had a partial or restricted capacity for work and what income he could earn. It is this decision that is appealed against.

7 Pursuant to s 247 of the Act leave to appeal from this court is required. The District Court is not to grant leave unless a question of law is involved and the amount in issue meets a certain threshold. There is no dispute between the parties that the threshold has been met and that leave to appeal should be granted.

8 Counsel for Mr Rintoul accepted that the issue whether the arbitrator had unduly restricted the issues that she should have decided upon involved an interpretation of s 61 of the Act and was a question of law.

9 Where the words in a statute can be given a variety of meanings, a value judgment is involved about the meaning of the particular provision and this is a question of law: Collector of Customs v Agfa-Gevaert Ltd [1996] HCA 36; (1996) 186 CLR 389, 394 - 396; Vurlow v Leighton Nursing Home [1978] WAR 15, 25.

10 Once the proper construction of a section has been determined the issue whether established facts fall within the words of a statute is also a question of law: Hayes v Federal Commissioner of Taxation [1956] HCA 21; (1956) 96 CLR 47, 51.

11 An error of mixed law and fact is an error of law: BHP Billiton Iron Ore Pty Ltd v Brady [2008] WASCA 250 [3]. Once a question of law is involved, the whole decision appealed from is open to review: Pacific Industrial Co v Jakovljevic [2008] WASCA 60 [18]. But a decision does not involve a question of law unless the error is material to the decision: Australian Broadcasting Tribunal v Bond [1990] HCA 33; (1990) 170 CLR 321, 353.

12 In interpreting s 61 as limiting the arbitrator's inquiry to the matters raised in the employer's notice, the arbitrator made a value judgment about the meaning of the statutory provisions and determined what issues were to be decided by her under s 61(3). If the arbitrator was in error in making this determination, she would have made an error of law.

13 In order to be granted leave an appellant does not have to establish that an error of law was indeed made by the arbitrator. All that the appellant has to show is that there is a real or significant argument to be put which involves a question of law: Secretary to the Department of Premier and Cabinet v Hulls [1999] VSCA 117; [1999] 3 VR 331 [10].

14 Accordingly, leave should be granted to Mirrabooka/Nollamara Car Transport to bring this appeal to the District Court and I do so.

15 Once leave to appeal has been granted, this court must undertake a 'real review' of the application before the arbitrator, but is limited to the materials before the arbitrator. It is not a hearing de novo. Before this court may disturb the arbitrator's decision the appellant must establish some error, either of fact, law or logic: Pacific Industrial Co v Jakovljevic [20] and [26].

16 The grounds of appeal relied upon by Mirrabooka/Nollamara Car Transport are that the arbitrator erred in law in firstly, failing to properly interpret and apply the provisions of s 61 of the Act and, secondly, in failing to provide any or adequate reasons for her decision. In amplification of the first ground the appellant essentially stated that the arbitrator:

(a) did not undertake an examination of the 'overall merits' of Mr Rintoul's entitlement to workers' compensation and did not consider the extent to which he retained some capacity for work;

(b) did not consider whether Mr Rintoul was still incapacitated at the time of the s 61(1) notice;

(c) erred when she held that the employer carried the burden of proof that the payments should be discontinued or reduced as the employer had made that assertion in the s 61(1) notice;

(e) erred when she held that the employer carried the burden of proof to show a novus actus, or break in the causal chain, between the current incapacity and the work injury; and

(f) erred when she held that the only issue to be decided was whether Mr Rintoul's continuing incapacity was the result of the work injury (which he had a burden to prove), when the correct issue to consider was what Mr Rintoul's current extent of incapacity was and whether the work injury was a material contributing cause to this incapacity (which Mr Rintoul had the burden to prove).

17 The second ground of appeal, the failure to provide adequate reasons, is particularised on the basis that the arbitrator did not consider the extent of Mr Rintoul's current incapacity and did not explain why she preferred the evidence of Dr Kennedy.

Section 61 of the Act

18 The first ground of appeal raises the question of how s 61 is meant to operate and who carries the burden of proof, if any, with regard to any matter to be established.

19 Section 61, insofar as is relevant, provides as follows:

1. Discontinuing or reducing weekly payments without order

(1) Subject to subsections (7) and (8) and section 84, where weekly payments of compensation for total or partial incapacity are made to a worker under this Act, they shall not be discontinued or reduced without the consent of the worker or an order of an arbitrator unless the worker has returned to work or a medical practitioner has certified that the worker has total or partial capacity for work or that the incapacity is no longer a result of the injury and a copy of the certificate (which shall set out the grounds of the opinion of the medical practitioner) together with at least 21 clear days' prior notice of the intention of the employer to discontinue the weekly payments or to reduce them by such amount as is stated in the notice, has been served by the employer upon the worker and unless within that period the worker has not made an application under subsection (3).

(3) A worker who disputes the right of his employer to discontinue or reduce the weekly payments referred to in subsection (1) may, within the period of notice given under that subsection or, if the employer fails to give the notice required under that subsection, within the period of 21 days or such further time as an arbitrator may allow from the day on which the weekly payments were discontinued or reduced, apply for an order of an arbitrator that the weekly payment shall not be discontinued or reduced.

(4) Upon the hearing of an application referred to in subsection (3) an arbitrator shall -

(a) adjourn the application on such terms as the arbitrator thinks fit; or

(b) dismiss the application in which case the weekly payments may be discontinued or reduced, as the

(c) make an order as to weekly payments by the employer to the worker on such terms as the arbitrator thinks fit.

(4a) Upon the hearing of an application referred to in subsection (3) an arbitrator -

(a) may, where the case requires, take into account whether -

(i) a return to work program has been established for the worker under section 155C(1); and

(ii) the establishment, content and implementation of the return to work program are in accordance with the code as defined in section 155; and

and for the purposes of determining the application accordingly treat the worker's incapacity as being of such degree as the arbitrator sees fit; and

(b) shall, where the case requires, take into account matters referred to in clause 8.

20 Upon a reading of the words of s 61(1) in their plain and ordinary meaning, it is apparent that an employer may not discontinue or reduce the weekly payments, without the consent of the worker or an order of an arbitrator, unless the worker has returned to work or a medical practitioner has certified that the worker has total or partial capacity for work or that the incapacity is no longer a result of the work injury. In addition, the employer has to serve a notice on the worker at least 21 clear days prior to the day on which the employer intends to discontinue or reduce the weekly payments. The notice has to be accompanied by a certificate setting out the grounds of the opinion by the medical practitioner that the worker has total or partial capacity for work or that the incapacity is no longer a result of the work injury. If the notice involves an intention to reduce the weekly payments, the notice needs to state by what amount the payments are to be reduced.

21 Section 61(1) has been on the statute books in a slightly different form since the Workers' Compensation and Assistance Act 1981 (the predecessor to the Act) became operative on 3 May 1982. The original s 61 contained essentially the same provisions, save that there was reference to 'the Board', rather than the arbitrator and the medical practitioner had to certify that the worker had 'wholly or partially recovered' (rather than 'has total or partial capacity for work') or that the incapacity was no longer 'as a result of the disability' (rather than that the incapacity was no longer 'a result of the injury'). The original section also referred to giving notice of the intention to 'diminish' the weekly payments rather than to reduce them.

22 Section 61 has been amended from time to time until it gained its current format. The last amendment was proclaimed under the Workers' Compensation Reform Act 2004 which became operative on 14 November 2005. For purposes of this appeal and the case law relied upon by the parties, the changes made to s 61(1) appear to be immaterial.

23 In Qantas Flight Catering v Joncevski [2004] WASCA 121 [8] Murray J, with whom Roberts-Smith and McLure JJ agreed, held that this section had a considerable lineage in the Act and that a provision in substantially the same form had existed since at least 1973. Murray J referred to Vurlow v Leighton Nursing Home where the interpretation of s 12B of the Workers Compensation Act 1912 - 1975 was in issue. Section 12B was in substantially the same terms as s 61 in its earlier format.

24 In Vurlow (19) Wickham J undertook an analysis of the various sections dealing with weekly payments made by an employer to a worker and came to the conclusion that an application under s 12B was designed to prevent an employer from arbitrarily ceasing weekly payments and that an application under that section was essentially interlocutory. Brinsden J also held (25) that proceedings under s 12B were interlocutory and that it was not the function of the Board to determine 'entitlement or liability pursuant to the claim'.

25 In Qantas Flight Catering the issue under consideration was whether the worker's entitlement to weekly payments should be canvassed at all where the employer had discontinued the weekly payments without serving a s 61 notice, but the worker had brought an application under s 61(3). Murray J held (at [18], [21]) that where the employer was in breach of its obligations under s 61, the employee was entitled to continuation of the weekly payments on the mere proof of the breach. On the other hand, if the employer had followed the statutory procedure, there was 'capacity to examine the merits of the worker's entitlement to compensation'.

26 In Heat Containment Industries v Kimberley (1990) 2 WAR 47, 49 and 57 - 58 Rowland J, with whom Ipp J agreed, held that the primary issue to be decided upon an application under s 61(3) was whether the employer's notice was compliant with s 61(1). The Board was only entitled to hear medical or other evidence regarding 'the merits' of the application, if the notice and certificate were valid. 'The merits' were described as being 'the dispute which the Applicant has with the facts or opinions contained in the certificate'.

27 Rowland J explained that an application under s 61(3) was intended to allow a genuine dispute as to whether the worker had recovered sufficiently to get back to work and related matters to be dealt with in an interlocutory and speedy matter. An application by the worker under s 61(3) could not be used by the employer to debate issues such as whether the worker had suffered a disability at all or whether the disability was suffered in the course of the worker's employment. Rowland J noted that there were other procedures laid down in the Act for the resolution of these questions and for hearings that were meant to dispose of the proceedings on a more permanent basis.

28 In Glenn-Craig Villages Pty Ltd v Donaghy (1992) 7 WAR 122, 129 the Full Court of the Supreme Court of Western Australia referred to Heat Containment Industries and agreed that the evidence heard by the Board upon an application under s 61(3) should be limited to the matters raised in the medical certificate, as the Act provided other mechanisms for solving disputes regarding whether the worker had suffered a disability at all or whether the injury was work-related.

29 The 'other mechanisms' in the Act for solving disputes about weekly payments are s 60 and s 62. Pursuant to s 60(1) an employer may apply at any time for an order of an arbitrator that weekly payments made to a worker should be discontinued or reduced. Under s 60(2) the arbitrator may order that the payments be suspended for some time if the employer satisfies the arbitrator that there is a genuine dispute as to liability to pay compensation or the proper amount of the weekly payments.

30 Pursuant to s 62 a weekly payment may be reviewed by an arbitrator on an application by either the employer or the worker and the arbitrator may discontinue, reduce, increase or suspend the weekly payment as he or she sees fit, having regard to the past or present condition of the worker.

31 In fact, Mirrabooka/Nollamara Car Transport has also applied under s 62 for a review of the weekly payments made to Mr Rintoul and has sought discontinuance of these payments. It has further applied under s 71 for a refund of any weekly payments made to Mr Rintoul, should the arbitrator upon the review find they were no longer due. A conciliation conference has taken place in June 2015 with regard to the application under s 62 and s 71 and the review has proceeded to a hearing before the arbitrator on 19 October 2015. The arbitrator has reserved her decision with regard to that hearing.

32 Mr Rintoul did not challenge the validity of the notice and the certificate. The main issue in contention in this appeal is whether, once the employer has filed a valid notice under s 61(1) to discontinue the weekly payments, the arbitrator has to decide afresh the whole matter of whether the worker is entitled to any weekly payments at all and to what extent.

33 Counsel for Mirrabooka/Nollamara Car Transport relied on Qantas Flight Catering where the employer had not given any notice under s 61(1) but discontinued the weekly payments because of a dispute regarding the worker's vocational rehabilitation. In that case it was held that the employer had unlawfully discontinued the weekly payments without the appropriate notice. Murray J held (at [21]) that where the employer was in breach of its obligations under s 61(1) the worker's entitlement to the reinstatement of weekly payments could be enforced on the mere proof of the breach. However, Murray also noted (at [18]) that where a valid notice had been served and the worker had made an application under s 61(3) there would be a capacity to examine 'the merits of the worker's entitlement to compensation'. Counsel for Mirrabooka/Nollamara Car Transport submitted that this meant the 'overall merits' could be examined and the worker had to prove afresh his entitlement to weekly payments and the exact reduction in wages by reason of his ongoing incapacity.

34 Counsel for the employer further relied on the decision by the Full Court of the Supreme Court of Western Australia in Cord Nominees Pty Ltd T/as Hardchrome Sales v Gomes (Unreported, WASCA, Library No 8520, 28 September 1990). In that case the employer had served a notice under s 61(1) advising the employee of its intention to discontinue the weekly payments. The notice did not refer to a reduction of weekly payments. Nevertheless, the issue of whether the worker had a retained a partial capacity to work had been dealt with in three medical reports which served as the certificate supporting the notice. It appears that evidence was placed before the Board regarding the type of work the worker was still capable of performing and the wages he was able to earn, as the Board found that the worker had the capacity to work as a driveway attendant at a service station for a specified amount of wages per week. However, the Board held that because the notice had only sought a discontinuance of payments, it was not within the power of the Board to make an order reducing the amount of the payments.

35 On appeal Malcolm CJ, with whom Kennedy and Ipp JJ agreed, held that the Board was not prevented from ordering a reduction of the weekly payments, even though the notice had not referred to a reduction. Malcolm CJ concluded that because s 61(4) gave power to the Board to adjourn the application by the worker, dismiss it and order the discontinuation or reduction of the weekly payments or make an order as to the weekly payments the Board thought fit, there was no justification for limiting the power of the Board to an order for discontinuance, merely because the notice had only referred to discontinuance.

36 The Full Court held (at (7)) that it had been open to the Board to order a reduction in the payments 'all the relevant evidence having been presented to it'. Malcolm CJ concluded that if the Board was unnecessarily limited in its powers, the employer could simply bring a further notice, based upon the same medical opinions, seeking a reduction in the weekly payments. This would merely result in all the evidence being considered once more.

37 However, the court also expressed the view (at (8)) that much was to be said for a proposition that the worker should be entitled to know precisely what action the employer would take if the worker did not make an application under s 61(3) and that it might be permissible to express a notice under s 61(1) on the basis that a reduction of payments was sought in the alternative. The court expressed doubt that the Board had the power to amend a notice under s 61(1), but declined to decide any of these matters as they had not been argued before the court.

38 The decision in Cord Nominees supports the argument by counsel for Mirrabooka/Nollamara Car Transport on a prima facie basis, but it is apparent from the decision that the issue of whether the worker had a retained capacity for work, in what types of occupation he could work and what wages he could earn, was fully canvassed and the Board actually found that he was capable to work as a driveway attendant for wages in a specified sum per week.

39 It makes sense on a practical basis that where all the necessary evidence had been heard by the Board, a decision should have been made by it dealing with the reduction of the weekly payments. The decision in Cord Nominees has to be seen in the light of the particular circumstances applying to that case. The Full Court did not decide the issue whether the notice could have been amended or put on an alternative basis.

40 In Mr Rintoul's case the parties did not agree to all the relevant evidence regarding a reduction of his weekly payments to be heard. It would be entirely contrary to the principles of natural justice, by which an arbitrator is bound pursuant to s 188(1) of the Act, if the arbitrator could make a finding on the worker's retained capacity to work and reduce his payments, without the worker having been given any notice that this issue was going to be decided at the s 61(3) hearing and without affording the worker the opportunity to deal with this issue.

41 In Vurlow v Leighton Nursing Home Burt CJ emphasised (at 16) with regard to s 12B (the equivalent to s 61) that the certificate of the medical practitioner was required to certify the existence of one of the three matters on which the employer's notice could be based, namely that the worker had wholly recovered, that he had partially recovered or that his incapacity was no longer a result of the injury. The matters that a s 61(1) notice may rely on are slightly different, namely that the worker has total capacity for work, or partial capacity for work or that the incapacity is no longer a result of the injury. Nevertheless, the point remains that the medical practitioner has to certify which of these matters applies. In Vurlow it was held that a medical report to the effect that the worker's condition had substantially improved did not comply with this requirement.

42 Wickham J (at 20) and Brinsden J (at 25) both emphasised that the certificate had to formally attest that at least one of the requirements had been met. The certificate had to be positive, unambiguous and not vague. A report by a medical practitioner in general terms would not meet that requirement if it was equivocal and incomplete.

43 It is generally accepted that where the certificate does not comply with s 61(1) the arbitrator cannot order discontinuance or the reduction of the weekly payments. If the certificate is not valid or does not contain the information required, that is the end of the matter: Heat Containment Industries (58); Qantas Flight Catering [11], [16] and [21].

44 In this case Mr Rintoul conceded that the notice and supporting certificate (in the form of the two reports by Dr Meyerkort, dated 30 May 2014 and 24 September 2014) were valid. The reports are in my view somewhat ambiguous, but Dr Meyerkort did state in the second report that he was 'not of the opinion' that the work incident 'caused him any further incapacity'.

45 The basis on which Dr Meyerkort has arrived at that conclusion is not entirely clear. In the report of 30 May 2014 at par 6 he stated that 'it is likely' that Mr Rintoul's work injury would have resolved within eight to 12 weeks and that any ongoing symptoms were more likely to have arisen as a result of degenerative changes in the back and neck and Mr Rintoul's morbid obesity. However, the report also seems to indicate that Mr Rintoul had the degenerative changes and suffered from morbid obesity prior to the work accident when he had no pain. Dr Meyerkort does not explain what role the work injury had to play, if any, in causing the pre-existing degenerative changes and the morbid obesity to become symptomatic and cause incapacity.

46 Counsel for Mirrabooka/Nollamara Car Transport accepted that an employer has 'to take the worker as he finds him', namely with pre-existing medical conditions, but Dr Meyerkort does not seem to have made his findings on that basis.

47 Dr Meyerkort seems to have accepted (under the heading 'Diagnoses' and 'Assessment' in his report of 30 May 2014) that Mr Rintoul was still suffering from neck and back pain, but stated that his weight was the 'most significant' contributing factor to this. Dr Meyerkort did not say that the morbid obesity and the degenerative changes were the only contributing factors at this stage or that they were likely to have caused the neck and back pain in any event, even without the work injury occurring. This seems to indicate that Dr Meyerkort did not exclude that the work injury made a material contribution to Mr Rintoul's ongoing back and neck pain.

48 Apart from stating that in his opinion the current incapacity suffered by Mr Rintoul was not caused by the work incident Dr Meyerkort also commented in his reports that Mr Rintoul was fit to work in a restricted capacity. He noted which postures and movements Mr Rintoul should avoid and suggested that he could perform logistics and administrative tasks for his employer.

49 The two reports by Dr Meyerkort are in my view ambiguous and confusing, but it was accepted by Mr Rintoul's counsel at the hearing before the arbitrator and on appeal that the s 61 notice and supporting certificate (being the two medical reports) were valid. However, the arbitrator was only prepared to accept that the notice and supporting reports were valid insofar as the employer had relied on its right to discontinue the weekly payments; not to reduce them. The arbitrator made the point that s 61(1) required that if the employer intended to reduce the weekly payments, it had to state in the notice the amount to which they were to be reduced (AB 112 [35]).

50 The arbitrator therefore came to the conclusion that the issue before her was constrained by the terms of the notice and the reports by Dr Meyerkort to the question whether the payments should be discontinued on the basis that Mr Rintoul's incapacity no longer related to the work injury (AB 110 - 111 [24] - [28]).

51 Counsel for Mirrabooka/Nollamara Car Transport submitted that it had been made clear by his client in respect of the proceedings before the arbitrator that it was relying not only on Mr Rintoul having gained full capacity to work, but also, in the alternative, to him having a retained partial capacity to work. Counsel referred to the certificate of outcome of the conciliation conference, dated 26 November 2014, which stated: 'The substantive issue in dispute between the parties therefore concerns the capacity of the worker and the cause of any continuing incapacity'. In my view, the certificate merely says that it was in issue whether the worker had a retained incapacity which arose from the work injury. The certificate does not state that the exact extent of the worker's incapacity and his ability to hold down particular jobs were in issue. In any event, this statement cannot reflect what exactly was in issue at the hearing before the arbitrator.

52 Counsel for Mirrabooka/Nollamara Car Transport also relied on the reply filed by his client to Mr Rintoul's application brought under s 61(3). The reply included Annexure A in which the employer had to indicate what issues in the worker's application were disputed and had to be determined. Annexure A stated that the employer disputed that Mr Rintoul continued to be incapacitated by reason of any compensable injury sustained during the work incident. The annexure further said the employer 'otherwise puts into issue the extent of any ongoing incapacity in the event that the Applicant continues to be incapacitated by reason of the compensable injury'.

53 I accept that Mirrabooka/Nollamara Car Transport indicated in the reply that it also wished to deal, in the alternative, with the question whether Mr Rintoul had a retained but restricted capacity to work. The transcript of the hearing before the arbitrator also shows that counsel for the employer on that day submitted that the arbitrator should not only consider whether Mr Rintoul's current incapacity arose from the work injury, but also in the alternative, the level of any retained capacity and whether he could work to some extent (AB 139). However, the transcript further shows that counsel for Mr Rintoul stated that no evidence had been filed in that regard because the issue of reduced payments had not been raised in the notice (AB 140).

54 At the hearing of the appeal counsel for Mirrabooka/Nollamara Car Transport conceded that no evidence had been led by either party at the hearing before the arbitrator with regard to Mr Rintoul's retained capacity for work, what jobs were available to him and what wages he could earn.

55 The mere fact Dr Meyerkort came to the conclusion in his reports that Mr Rintoul had a retained capacity to work for his previous employer in logistics or administration and that counsel for the employer mentioned at the hearing before the arbitrator that his client wished this issue to be heard, does not mean that the question whether the worker had partial capacity for work was properly raised in the notice under s 61(1) or the accompanying certificate, nor that it was dealt with at the hearing.

56 Counsel for Mirrabooka/Nollamara Car Transport further submitted that because s 61(4)(a) provides for an arbitrator, upon hearing a s 61(3) application, taking into account whether the worker had returned to work or had participated in a return to work programme and could 'for the purposes of determining the application accordingly treat the worker's incapacity as being of such degree as the arbitrator sees fit', the arbitrator was always entitled to assess the degree of the worker's incapacity upon a hearing of a s 61(3) application. However, s 61(4)(a) explicitly states that the arbitrator may take into account these matters 'where the case requires'. In my view the arbitrator's right to determine the degree of the worker's incapacity under s 61(4)(a) only has application where the notice under s 61(1) refers to the employer's intention to reduce the weekly payments by a particular amount.

57 Counsel for Mirrabooka/Nollamara Car Transport relied on the obiter view expressed in Cord Nominees, that an employer could not amend a s 61(1) notice once it had been filed. This, counsel submitted, again made it imperative that the arbitrator should be able to not only deal with the ongoing incapacity and its cause, but also with the question whether there was a retained capacity for work.

58 This is not a persuasive argument. If indeed a s 61 notice cannot be amended, an employer who has mistakenly limited its notice to an intention to discontinue the weekly payments simply has to file a further notice. If the first notice has not yet been heard, it could presumably be withdrawn or both notices could be heard at the same time. Difficulties regarding procedure cannot override the important consideration that a worker should be given notice of what exact steps the employer intends to take and what contentions he or she needs to defend. In any event there is no reason why a s 61(1) notice cannot be formulated in the alternative.

59 Counsel for Mr Rintoul pointed out that should the employer make weekly payments for a longer period than justified, it could bring an application under s 71 of the Act for a refund of any payments to which the worker was not lawfully entitled.

60 In my view the arbitrator did not err when she held that she was limited by the s 61 notice to decide whether Mr Rintoul's ongoing incapacity was causally linked to the work injury. It is clearly a requirement of s 61(1) that the employer state in the notice whether it intends to discontinue the weekly payments or reduce them and to what amount.

61 Counsel for Mirrabooka/Nollamara Car Transport submitted that the arbitrator had never put her mind to the question whether Mr Rintoul was still incapacitated; she had simply assumed that he was and had only looked at whether his incapacity was causally linked to the work injury. However, the arbitrator quoted at length from Dr Kennedy's report, dated 9 June 2015, in which he stated that he had reassessed Mr Rintoul on 8 June 2015 and had come to the conclusion that he continued to have significant problems in his neck, back and both hands (AB 122 [83]). The arbitrator also referred to Dr Kennedy's AMS 5 report, dated 16 June 2015, in which Dr Kennedy certified Mr Rintoul to have a whole person impairment of 18% based on a 'chronic cervical and lumbar mechanical injury' which was sustained following a fall at work. The arbitrator did not quote from the AMS 5 report in her decision, but stated that Dr Kennedy had provided an evaluation of the degree of permanent impairment (AB 123 [84]).

62 The arbitrator noted that both Drs Kennedy and Meyerkort had provided their opinion in relation to the issue before her, but said she preferred the evidence of Dr Kennedy. She specifically concluded that Dr Kennedy's evidence together with that of Mr Rintoul's treating general practitioner supported the contention that Mr Rintoul was continuing to suffer incapacity as a result of the compensable injury (AB 133 [136]). She made reference to the fact that there was a continuous presentation of symptoms dating from the date of the injury.

63 In light of these findings it cannot be said that the arbitrator did not put her mind to the question whether Mr Rintoul was still incapacitated.

64 Counsel for Mirrabooka/Nollamara Car Transport submitted that any prejudice caused to Mr Rintoul by no evidence having been led at the hearing about his level of retained capacity and occupations suitable to his limited capacity was due to his own making, as the worker carried the burden of proof under s 61(3) to show that his employer should not be entitled to discontinue or reduce the weekly payments. Counsel submitted that this was the case on the basis of the maxim of 'he who alleges has to prove'.

65 I have already found that the issue whether Mr Rintoul retained a partial capacity to work was not a matter before the arbitrator, and the question who carried the burden of proof to establish Mr Rintoul's reduced level of capacity, in what occupation he could work and for what wage therefore did not arise.

66 However, the issue whether the arbitrator applied the correct principles regarding the burden of proof when she decided whether the payments should be discontinued is still relevant. Counsel for Mirrabooka/Nollamara Car Transport submitted that the arbitrator erred when she stated that the employer carried an onus to prove that the payments should be discontinued.

67 Before dealing with the statements made by the arbitrator about the burden of proof, it should be noted that the arbitrator correctly dealt with the issue of causation (AB 129 - 132 [118] - [124]). She relied on Leggett v Argyle Diamond Mines Pty Ltd [2000] WASCA 182 [22] - [26] for the proposition that as long as the work injury had made a material contribution to the existing incapacity there was a causal link between the two, unless a supervening factor, a novus actus interveniens, had come into operation so as to displace in the eyes of the law the original injury as the cause of the incapacity.

68 The arbitrator also referred to Ward v Corrimal-Balgownie Collieries Ltd [1938] HCA 70; (1938) 61 CLR 120 and Wilson v Bentley Health Service [2007] WACC C31-2007 for the proposition that an employer is required to take the worker as it finds him and that where a pre-existing disease or condition is made symptomatic or aggravated by a compensable injury, the worker is entitled to compensation as long as the work injury made a material contribution to the incapacity (AB 130 [122] - [124]).

69 To this should be added that the worker is entitled to be compensated for his full incapacity, unless the incapacity resulting from the pre-existing condition can be separated from the incapacity arising from the work injury or it can be shown that the worker would in any event have suffered from the incapacity in due course as a result of the pre-existing condition: Purkess v Crittenden [1965] HCA 34; (1965) 114 CLR 164, 168 and 170.

70 It is generally accepted that the same principles applying to causation in tort law, also apply to proof that the worker's incapacity is causally related to his work injury: Cole v P & O Ports Ltd [2002] WASCA 157, [22] - [24] and Kanowna Belle Goldmines v Feierabend [2003] WASCA 246, [12] - [13].

71 Turning now to the burden of proof, it is well established in tort law that the plaintiff bears the legal burden of proof that his or her loss or disability has been caused by the tort or accident. Proof that the tort made a material contribution to the loss or disability is sufficient: Watts v Rake [1960] HCA 58; (1960) 108 CLR 158, 159 - 160.

72 However, where there are competing causes, in addition to the tort or accident, which contributed to the loss or disability Dixon CJ in Watts v Rake (160) explained the burden of proof as follows:

If the disabilities of the plaintiff can be disentangled and one or more traced to causes in which the injuries he sustained through the accident play no part, it is the defendant who should be required to do the disentangling and to exclude the operation of the accident as a contributory cause. If it be the case that at some future date the plaintiff would in any event have reached his present pitiable state, the defendant should be called upon to prove that satisfactorily and moreover to show the period at the close of which it would have occurred.

73 In Purkess v Crittenden (168) and (170), the High Court made it clear that the onus of proof referred to by Dixon CJ in Watts v Rake was an evidentiary onus (a burden to place relevant evidence before the court) and that the overall legal onus of proving that the tort or accident made a material contribution to the plaintiff's injuries remained with the plaintiff.

74 If these principles regarding the burden of proof in tort law were applied to workers compensation, the worker would upon an application for compensation carry the legal burden of proving that his incapacity was caused, in the sense of materially contributed to, by the work injury and the employer would have an evidentiary burden to show that there were pre-existing conditions which would in any event have resulted in the current incapacity or new causes which broke the chain of causation between the work accident and the worker's incapacity.

75 The arbitrator made the following findings regarding the burden of proof (at AB 111 - 112):

1. Section 61 does not specify what onus any party carries. Accordingly, it is appropriate the maxim 'he who asserts must prove' should apply.
2. Pursuant to a s 61 application the worker is disputing the employer's right to discontinue (in this case) his weekly payments.
3. The Applicant worker therefore bears the onus of establishing on the balance of probabilities that his ongoing incapacity does relate to the compensable injury.
4. The worker through their application is seeking to show the arbitrator that the action outlined in the notice does not occur. In these circumstances, it must follow the employer still carries an onus to prove the payments should be discontinued or reduced as the employer was initially making this assertion.
5. On this basis, if a worker has been served with a notice seeking to discontinue payments on the basis that his incapacity no longer results from the compensable injury and it is found that causal connection has not be severed, it does not follow that he or she then bears the onus to prove capacity.

76 The arbitrator held (at [32]) above that the worker bore the onus of establishing on the balance of probabilities that he had an ongoing incapacity which was causally related to the compensable injury. Having made that finding, it does not make sense to say, as she did (at [33]), that the employer still carried an onus to prove that the payments should be discontinued or reduced, unless the arbitrator had in mind an evidentiary onus to place the relevant evidence before the arbitrator. Such evidence could have been evidence of a subsequent event or disease which broke the chain of causation (relevant to discontinuance) or, if this had been relevant, evidence regarding the worker's ability to work in certain occupations (relevant to a reduction of payments). The arbitrator's statements (at [34]) seem to support that she had an evidentiary burden in mind, as she referred in that paragraph to the worker not having a burden to prove 'capacity' once he had proven his ongoing incapacity arising from the work injury. The reference to 'capacity' can only mean 'extent of capacity'.

77 My understanding of the arbitrator's findings are that she placed a legal burden on Mr Rintoul to prove that his current incapacity was still causally linked to the work injury and an evidentiary burden on the employer to provide evidence of a novus actus or break in the chain of causation.

78 However, even if the arbitrator made an error in placing either a legal or an evidentiary burden of proof on the employer, it did not affect the outcome of her decision. She decided that the only issue was whether the payments should be discontinued on the basis that Mr Rintoul's current incapacity did not arise from the work injury and came to the conclusion that she was satisfied on the basis of Dr Kennedy's reports and that of Mr Rintoul's general practitioner that Mr Rintoul had an ongoing incapacity which resulted from his work injury (AB 133 [136]). This was not a case where the decision maker came to the conclusion that a finding could not be made on a balance of probabilities because of the lack of evidence to support the finding.

79 Having found that the ongoing incapacity was the result of the work injury, the arbitrator said that she was satisfied that the payments should not be discontinued and that, 'in addressing the merits of the Notice', she was unable to find that Mr Rintoul's incapacity no longer resulted from the work injury (AB 133 [137] and [138]). The fact that the arbitrator put her finding in terms of her being 'unable to find' does not mean that she concluded that the employer had presented insufficient evidence for her to find that the incapacity no longer resulted from the work injury. She simply put her finding in the language of the s 61 notice.

80 Counsel for Mirrabooka/Nollamara Car Transport further submitted that the arbitrator had placed the burden of proving that Mr Rintoul's weight gain after the work incident was a novus actus on the employer and that she had erred in that regard. Counsel submitted that the arbitrator did so when she came to the conclusion (at AB 132 [130] and [131]) that the weight gain referred to by Dr Meyerkort could not be characterised as a novus actus. However, the fact that the arbitrator did not accept the evidence presented by the employer in this regard, does not mean that she placed a legal burden of proof on the employer to prove the intervening cause or novus actus. It simply shows that she considered and evaluated all the evidence before her.

81 It should be remembered that the burden of proof or legal onus only becomes relevant where the decision maker is unable to make a finding on a particular issue: Cross on Evidence (9th Aust ed, 2013), [7010]. If the decision maker is able to make a finding on the evidence before him or her, it does not matter who carried the burden of proof. Accordingly, even if the arbitrator erred in placing a legal onus on the employer to prove a novus actus or that the payments should be discontinued, it is an error of no import, as the arbitrator did not find that she was unable to reach a decision in that regard.

82 As explained in Australian Broadcasting Tribunal v Bond (353), a decision does not involve an error of law, unless the error is material to the decision, in the sense that it contributes to the result, so that but for the error the decision may have been different.

83 The mere fact that the arbitrator referred to the burden of proof and may have incorrectly allocated a burden of proof to the employer to prove that the payments should be discontinued also does not mean that she misunderstood the matters that she had to decide on the available evidence before her. In Lodkowski v Comcare (1998) 53 ALD 371, Goldberg held that the use by an administrative tribunal of language appropriate to an onus of proof analysis did not necessarily mean that the tribunal misapprehended the matters of which it had to be satisfied in reaching a decision on the matters before it. The same applies in this case. The arbitrator had the necessary evidence before her to make the decision and she arrived at an appropriate decision on the evidentiary material before her. It did not matter who had the burden of proof, if any, to place this material before her or prove any particular issue.

84 In any event, I am not persuaded that the arbitrator did place a legal burden of proof on Mirrabooka/Nollamara Car Transport to establish a novus actus or show that the payments should be discontinued. In light of the fact that she placed the overall burden on Mr Rintoul to show that his ongoing incapacity was still causally linked to the work injury (AB 111 [32]), she is more likely to have meant an evidentiary burden when she referred to the employer's onus to prove that the payments should be discontinued (AB 111 [33]).

85 As the decision of the arbitrator is not affected by any error that she may have made with regard to the allocation of the burden of proof, it is not strictly speaking necessary for me to decide which party carries the burden of proof upon an application under s 61(3) to show that payments should be discontinued or reduced. However, because the issue was argued to some extent during the hearing of the appeal, I shall summarise the issues raised by the parties and express my view. It should be said that the issue of who carries the burden of proof when an application under s 61(3) is made by the worker was not fully argued before me, as counsel for Mr Rintoul declined the offer by the court to file further submissions in that regard.

86 Counsel for Mirrabooka/Nollamara Car Transport submitted that the burden of proof was on Mr Rintoul to prove that his ongoing incapacity still resulted from the work injury, as he had been the one to allege this in his s 61(3) application. Counsel relied on the decision by the Full Court of the Supreme Court of Western Australia in Mayne Nickless Ltd t/as Wards Express v Mayne (Unreported, WASCA, Library No 960736, 19 December 1996) 19 where Pigeon J held that in the absence of the statute specifying on whom the onus lay, the normal rule was that the person who asserted must prove. However, the Mayne Nickless decision did not deal with s 61. It dealt with the question whether the review officer should have made further enquiries of his own accord when deciding the issue whether a worker was entitled to compensation on the basis that the work injury had materially contributed to an acceleration of her existing back condition. Pidgeon J merely noted in passing that the review officer was correct in saying that the onus was on the worker to prove that the work injury had made a material contribution.

87 The difficult question with regard to s 61 is: who is the party who asserts? It is the employer who serves a notice under s 61(1) stating that it intends to discontinue or reduce the weekly payments and who provides an accompanying medical certificate which states either that the worker has total or partial capacity for work or that the incapacity is no longer a result of the injury. It is therefore the employer who makes certain assertions. The worker may either accept the discontinuance or reduction of his payments or may make an application under s 61(3) for an order of an arbitrator that the weekly payments should not be discontinued or reduced. Does such an application mean that the worker makes the contrary assertions, namely that he is either totally incapacitated or partially incapacitated to a greater extent than certified by the employer's medical practitioner or that his incapacity is still the result of the injury?

88 Counsel for Mirrabooka/Nollamara Car Transport also relied on Mitchell v Canal Rocks Beach Resort [2002] WASCA 331 [10] - [11] and [52] - [55] where Templeman J and Roberts-Smith J, with whom Sheppard AUJ agreed, held that the burden of proof was on the worker upon an application for compensation under sch 1, cl 7 of the Workers' Compensation and Rehabilitation Act 1981 (WA) to prove either total incapacity, or in the alternative, partial incapacity and, in the latter case, how much less the worker was capable of earning at the time in comparison to before the work injury. Roberts-Smith J came to the conclusion that the legislation did not adopt the approach that a worker was encouraged to take a passive role in his own application for compensation. It was therefore not open to the worker to simply assert that he was totally incapacitated and then to expect the employer to present evidence of the worker's retained partial capacity and the wage that he was still capable of earning.

89 Two observations should be made about that case. Firstly, this was an initial application by the worker under sch 1 cl 7 for weekly payments. The Canal Rocks Beach Resort case did not concern a notice under s 61(1) or an application under s 61(3) which occurs after the worker has already established his entitlement to weekly compensation.

90 Secondly, in my view the case should not be read as a rejection of the general principles applied in tort law that once a plaintiff or a worker relies on a reduced capacity to work and provides some evidence to support this, there is an evidentiary burden on the defendant or employer to present evidence of more strenuous and higher paid jobs which it asserts the plaintiff or worker can perform. The problem in the Canal Rocks Beach Resort case was that the worker had only relied on his total incapacity to work and had argued that the burden to present evidence regarding jobs that the plaintiff could still do was entirely on the employer if it wanted to rely on partial incapacity.

91 It was in this context that Roberts-Smith J held that the burden of proving the claim in its entirety rested with the applicant seeking compensation for the loss of employment and there could be no shifting of the evidential burden unless some evidence had been led to show that the worker had made efforts to identify suitable jobs open to him. His Honour also made the point that although the burden of proof was on the worker seeking compensation, his or her claim would vary according to the circumstances of the disability and it would be for the employer to negative that claim with evidence.

92 Counsel for Mirrabooka/Nollamara Car Transport further referred the court to the decision in Margaret Roney v Accommodation West Pty Ltd [2009] WACC C10-2009 [26] where Commissioner McCann compared the procedure under an application pursuant to s 61(3) with an application for a review of the weekly payments under s 62. Commissioner McCann held that the certificate issued by a medical practitioner for purposes of s 61(1) was 'intended to provide immediate legal certitude as to the rights and obligations of the parties; it had provisional legal force in its own right'. Commissioner McCann relied as authority for this statement on his decision in Compass Group (Australia) Pty Ltd v Delides [2009] WACC C1-2009 [19] which concerned the adequacy of a certificate under s 61(1). Taken in its proper context, it is apparent that the statement about 'legal certitude' and 'provisional legal force' was made in order to emphasise that the certificate had to address the criteria in s 61(1) in clear and unequivocal terms, as in the absence of the worker challenging the notice, the certificate would be determinative. Commissioner McCann did not convey any notion that such a certificate presented some standard of legal proof or presumption which, even if the worker made an application before the arbitrator, remained determinative and shifted the burden of proof onto the worker to establish the contrary findings.

93 It has generally been accepted that where the employer makes an application for a review of weekly payments under s 62, it carries the burden to prove that the payments should be adjusted: Andromeda Kosters v Coles Supermarkets Australia Pty Ltd (Unreported, CM-43/98 (Cockram PG) 14 September 1998); Jupero Pty Ltd v Karl Finnis (Unreported CM-6/00 (Packington J) 20 June 2000); Denken Pty Ltd v Judith Footer (Unreported, CM-236/01 (Hogan PM) 29 August 2002).

94 In my view, there is no apparent reason why the burden of proof should be different between a situation where an employer makes an application for a review of the weekly payments under s 62 and where it is called upon to prove its assertion made in a s 61(1) notice and accompanying medical certificate that payments should be discontinued or reduced. It is after all the employer who asserts in the medical certificate that the worker has regained total capacity to work or at least partial capacity or that his ongoing incapacity is no longer the result of the work injury. Other than the fact that it is upon the worker to make an application to the arbitrator under s 61(3) if he or she does not accept the notice and certificate, the worker does not apply to change the status quo which he or she has established by the original application for weekly payments.

95 It seems to me that if the employer wishes to change the status quo and asserts that the worker has regained full capacity or at least partial capacity or that the incapacity is no longer the result of the work injury, it should carry the legal burden to prove these matters and the worker would have an evidentiary burden to show that the situation had not changed or changed to a lesser degree than asserted by the employer.

96 However, my view of which party carries the legal onus does not mean that the arbitrator has made an appealable error. She seems to have placed the legal burden to disprove the matters relied upon in the s 61(1) notice on Mr Rintoul, which was a decision in favour of Mirrabooka/Nollamara Car Transport. But, in any event, the assessor did not rely on the burden of proof in order to decide whether Mr Rintoul's incapacity was no longer caused by the work injury. She made findings on the available evidence which were open to her. Her view of which party carried the burden of proof had no role to play in her decision making process.

97 Accordingly, no error arises from the findings made by the assessor regarding the burden of proof.

98 The second ground of appeal relied upon is that the arbitrator failed to provide adequate reasons in that she did not consider the extent of Mr Rintoul's current incapacity and did not explain why she preferred the evidence of Dr Kennedy.

99 In common law a judicial officer has a duty to give reasons: Wainohu v New South Wales (2011) 278 ALR 1 [55] - [56]. In Summit Homes v Lucev (1996) 16 WAR 566, 571, Ipp J held that the common law principles also applied to review officers who conducted hearings under the former regime applicable under the Act.

100 The function of reasons is to give effect to any right of appeal, to enable an appeal court to determine whether or not an appealable error was made, and to allow the parties to understand why they were or were not successful: Mount Lawley Pty Ltd v Planning Commission (WA) [2004] WASCA 149; (2004) 29 WAR 273 [27].

101 In Beale v Government Insurance Office (NSW) (1997) 48 NSWLR 430, 443 - 444, Meagher JA held that there were three fundamental elements of a statement of reasons. Firstly the judicial officer should refer to the relevant evidence on which he or she relied and where there was conflicting evidence both sets of evidence should be referred to. Secondly, a judicial officer should set out the material facts that were accepted and any conclusions that were reached and why one set of facts was accepted above another. Thirdly, a judicial officer should explain his or her reasoning in applying the law to the facts found.

102 Whether the extent of the reasons provided is adequate will depend on the circumstances of the case, including the nature of the jurisdiction being exercised: Wainohu [56]. It is also necessary to look at the reasons as a whole and to determine whether, in the context of the evidence, they give a sense of what was intended in a way that would have met the requirements for reasons: SNF (Australia) Pty Ltd v Jones [2008] WASCA 121.

103 These common law principles have to be applied in light of and subject to s 213(4) of the Act: Velez Pty Ltd v Tudor [2011] WASCA 218 [58].

(a) need only identify the facts that the arbitrator has accepted in coming to the decision and give the reasons for doing so; and

(b) need only identify the law that the arbitrator has applied in coming to the decision and give the reasons for doing so; and

(c) need not canvass all the evidence given in the case; and

(d) need not canvass all the factual and legal arguments or issues arising in the case.

105 In Velez Pty Ltd v Tudor [70] Murphy JA held that in identifying the facts accepted and the reasons for doing so and the law applied and the reasons for doing so, as required by the section, the arbitrator was still obliged to expose the reasoning process linking them and to justify the ultimate result.

106 In Peter Nardi v Department of Education and Training [2006] WACC C22-2006 [31] Commissioner McCann came to the conclusion that the common law principles still applied but were modified by s 213(4) of the Act. Commissioner McCann expressed the view that the purpose of s 213(4) was to promote expedition, simplicity and transparency in the giving of reasons for the decision, but that this section was not intended to encourage over-brevity, the compression of reasons to the point of obscurity, or the excessive use of implied reasoning.

107 It has often been said that the realities of pressure of work and limited time in the Magistrates Court must be acknowledged: Manonai v Burns [2011] WASCA 165 [56]. The same would apply to the workload of an arbitrator in the Dispute Resolution Directorate.

108 In Minister for Immigration and Ethnic Affairs v Wu Shan Liang [1996] HCA 6; (1996) 185 CLR 259, 272 the High Court held that reasons of an administrative decision-maker should not be scrutinised over-zealously by seeking to discern whether some inadequacy might be gleaned from the way in which the reasons were expressed.

109 In Sotico Pty Ltd v Wilson [2007] WASCA 112, Wheeler JA held that s 213(4) should be regarded against the factual context in which it was enacted, as arbitrators were frequently called upon to give reasons in cases where there was a significant number of medical reports, many of which would conflict with each other. An arbitrator should therefore not be required to engage in an exhaustive process of specifying which opinions were rejected and the reasons for their rejection. This would only be necessary where the rejected opinion attacked the reasoning process of the opinion accepted by the arbitrator. Wheeler JA stated that the arbitrator could provide his or her reasons for preferring a particular medical report either positively, by stating the reasons why the accepted report was considered more reliable, or negatively, by explaining why the attack on that report lacked substance.

110 I have already dealt with the fact that the arbitrator did consider whether Mr Rintoul's incapacity was still current and set out the findings by Dr Kennedy that she had relied upon in that regard (AB 122 - 123 [83] - [84]). She came to the specific conclusion that Mr Rintoul continued to suffer incapacity as a result of the work injury [AB 133 [136]).

111 The arbitrator also set out adequately why she preferred Dr Kennedy's evidence and rejected the opinion of Dr Meyerkort. She first explained that a worker would be entitled to compensation if the work injury still made a material contribution to his current incapacity (AB 130 [120] - [124]). She noted that Dr Meyerkort was of the opinion that the only reason for Mr Rintoul's current incapacity was his obesity. She referred to a statement in Dr Meyerkort's report that Mr Rintoul had weighed around 140 kg when he first saw Dr Meyerkort and that his weight had increased to 165 kg. The arbitrator therefore noted that it appeared that Mr Rintoul had been a large man prior to the accident and that the employer had to take the worker as he found him (AB 131 - 132 [128] - [129]).

112 What the arbitrator essentially said is that even if Mr Rintoul's obesity was a major contributing factor to his current incapacity, this was a pre-existing condition and as long as the work injury also made a material contribution to the current incapacity, Mr Rintoul was still entitled to compensation.

113 The arbitrator next dealt with the weight gain after the accident and said that this could not be characterised as a novus actus. She explained that Dr Kennedy had drawn 'a clear link between incapacity from a back injury and weight gain', meaning that weight gain was often a consequence of a back injury (AB 132 [129]).

114 The arbitrator therefore adequately explained why she rejected Dr Meyerkort's reliance on Mr Rintoul's obesity as a reason why his current incapacity was no longer causally linked to the work injury. She was perfectly entitled to come to this conclusion, as Dr Meyerkort did not explain in his reports why the pre-existing obesity should preclude Mr Rintoul from claiming compensation and did not state that Mr Rintoul would in any event have become incapable to work, irrespective of the injury, and purely as a result of his pre-existing obesity. Dr Meyerkort also did not say that the incapacity was solely due to the weight gain after the work injury and was unrelated to the accident.

115 The arbitrator next dealt with the question whether there was any other ground to support Dr Meyerkort's opinion. She rejected his reliance on Mr Rintoul having psychosocial issues on the basis that Dr Meyerkort had stated this to be outside his area of expertise and had not explained exactly what these issues were (AB 132 [132]).

116 The arbitrator next rejected Dr Meyerkort's reliance on Mr Rintoul having had 'issues with his employer'. She said there was no evidence of what these issues might have been and Mr Rintoul was not cross-examined in that regard, nor did Mirrabooka/Nollamara Car Transport provide any evidence to support such an allegation (AB 132 [133]).

117 The arbitrator further rejected Dr Meyerkort's reasoning that the work injury could not have been that serious because Mr Rintoul did not present for emergency treatment but drove his truck back to Perth. The arbitrator stated that in her view Mr Rintoul did not have much choice but to return the truck to Perth and on his arrival he immediately presented to his general practitioner (AB 132 [135]).

118 The arbitrator did not only explain why she rejected Dr Meyerkort's opinion on the causation issue, but also stated why she preferred the evidence of Dr Kennedy. Having set out substantial parts of Dr Kennedy's reports, she noted that his view that Mr Rintoul was continuing to suffer incapacity as a result of the work injury was confirmed by Mr Rintoul's general practitioner. The arbitrator further pointed out that this conclusion was supported by Mr Rintoul's continuous presentation of symptoms from the date of the injury (AB 133 [136]).

119 In my view there is no validity in the complaint that the arbitrator did not explain why she preferred the evidence of Dr Kennedy or did not give adequate reasons.

120 None of the grounds of appeal have been made out and the appeal is dismissed.