Donhad Pty Ltd v Asbury

Hearing dates: 11 December 2025

Date of orders: 18 December 2025

Decision date: 18 December 2025

Jurisdiction: Common Law

Before: Griffiths AJ

Decision: 1. The summons filed 17 June 2025 is dismissed, with no order as to costs.

Catchwords: ADMINISTRATIVE LAW — judicial review of appeal panel decision — assessment of whole person impairment — where appeal panel provided five different statements of reasons for decision and five corresponding medical assessment certificates — whether appeal panel erroneously failed to make a s 323 deduction for pre-existing injury, condition or abnormality — whether appeal panel failed to respond to clearly articulated argument — whether appeal panel made an irrational or illogical finding of fact — adequacy of reasons of appeal panel — no reviewable error established despite poor quality of appeal panel’s documentation

Legislation Cited: Workers Compensation Act 1987 (NSW), s 66
Workplace Injury Management and Workers Compensation Act 1998 (NSW), ss 319, 322, 323, 325, 328, 376

Cases Cited: Azzopardi v Tasman UEB Industries Ltd (1985) 4 NSWLR 139
Cole v Wenaline Pty Ltd [2010] NSWSC 78
Elcheikh v Diamond Formwork (NSW) Pty Ltd (in liq) [2013] NSWSC 365
Fullford v Maccas Ferry Services Pty Ltd [2016] NSWSC 1161
KFTJ v Minister for Immigration, Citizenship and Multicultural Affairs [2025] FCA 958
Minister for Immigration and Citizenship v SZMDS (2010) 240 CLR 611; [2010] HCA 16
Ryder v Sundance Bakehouse [2015] NSWSC 526
Secretary, Department of Communities and Justice v Virtue [2024] NSWSC 1380
Southwell v Qantas Airways Ltd [2024] NSWSC 497
Matthew Hall Pty Ltd v Smart [2000] NSWCA 284; 21 NSWCCR 34
State Super SAS Trustee Corporation v Cornes [2013] NSWCA 257
Tolson v Roads and Maritime Services [2014] NSWCA 161; 201 LGERA 367
Wingfoot Australia Partners Pty Ltd v Kocak (2013) 252 CLR 480; [2013] HCA 43

Texts Cited: NSW Workers Compensation Guidelines for the Evaluation of Permanent Impairment, 4th ed, 1 March 2021

Category: Principal judgment

Parties: Donhad Pty Ltd (Plaintiff)
Alan John Asbury (First Defendant, submitting appearance)
Appeal Panel constituted under s 328 of the
Workplace Injury Management and Workers
Compensation Act 1998 (Second Defendant, submitting appearance)
President of Personal Injury Commission of New South Wales (Third Defendant, submitting appearance)

Representation: Counsel:
B Jones (Plaintiff)
B Kaplan SC and J Tsaousidis (Amici Curiae)
Solicitors:
Hall & Wilcox (Plaintiff)
Santone Lawyers (First Defendant)
Crown Solicitor’s Office (Second and Third Defendant)

File Number(s): 2025/00231379

Publication restriction: Nil

JUDGMENT

Introduction

1. By a summons filed 17 June 2025, the plaintiff seeks judicial review of a decision dated 19 May 2025 (Final Decision) of an Appeal Panel constituted under s 328 of the Workplace Injury Management and Workers Compensation Act 1998 (NSW) (WIM Act). The Appeal Panel issued an amended medical assessment certificate under s 328(5) of the WIM Act assessing the whole person impairment (WPI) of the first defendant, Mr Alan Asbury, resulting from injuries sustained by him in October and December 2003 respectively.

2. The primary issues requiring determination are as follows:

(a) Whether the Appeal Panel made a jurisdictional error by failing to make a deduction under s 323 of the WIM Act in respect of Mr Asbury’s WPI in relation to his right knee (Ground 1). (b) Whether the Appeal Panel failed to provide adequate reasons as to why it did not make a deduction under s 323 of the WIM Act in relation to the WPI of Mr Asbury concerning his right knee (Ground 2). (c) Whether the Appeal Panel made a jurisdictional error by failing to respond to the plaintiff’s reliance on Basten AJ’s judgment in Secretary, Department of Communities and Justice v Virtue [2024] NSWSC 1380 (Ground 3). (d) Whether the Appeal Panel made an irrational finding of fact in assessing a 5% WPI relating to the injuries Mr Asbury sustained to his right knee in October 2003 despite its earlier finding that it was correct for the Medical Assessor to have applied all the impairment to the December 2003 injury (Ground 4). (e) Whether the Appeal Panel failed to provide reasons concerning the apportionment of Mr Asbury’s WPI referable to the injuries he sustained to his right knee in October and December 2003 (Ground 5).

Background matters summarised

3. After finishing work with the plaintiff on 21 October 2003, the first defendant (Mr Asbury) noticed his right knee was swollen. There is no dispute that on that date, Mr Asbury suffered an injury to his right knee which resulted in him developing consequential injuries to his left knee and right shoulder (collectively, the October 2003 Injuries). Mr Asbury returned to work with the plaintiff after the October 2003 Injuries.

4. During the course of his continuing employment with the plaintiff on 22 December 2003, Mr Asbury slipped on a ledge and fell. He could not get up, experiencing pain in his back and right knee. Again, there is no dispute that this incident caused Mr Asbury to suffer an injury to his right knee and consequential injuries to his left knee and right shoulder (collectively, the December 2003 Injuries).

5. Mr Asbury lodged two claims for compensation pursuant to s 66 of the Workers Compensation Act 1987 (NSW) against the plaintiff in respect of the October 2003 Injuries and the December 2003 Injuries respectively.

6. A dispute arose about Mr Asbury’s entitlement to compensation and both claims were referred collectively to the Personal Injury Commission (PIC). It is important to bear in mind that there were two separate but related claims which were referred for assessment.

7. By way of consent orders made by PIC Member Homan on 1 August 2024, the assessment of Mr Asbury’s WPI resulting from the October 2003 Injuries and the December 2003 Injuries was referred to Medical Assessor Dr Tommasino Mastroianni. The formal referral explicitly stated that it related to Mr Asbury’s right knee, left knee (consequential) and right shoulder (consequential).

8. Medical Assessor Mastroianni issued a Medical Assessment Certificate dated 3 October 2024 (MAC) pursuant to s 325 of the WIM Act.

9. In the MAC, Mr Asbury was assessed as having no rateable WPI in respect of any aspect of the October 2003 Injuries but as having a 25% WPI in respect of the December 2003 Injuries. This comprised 18% WPI for the right lower extremity (knee), after a 1/10th deduction was made pursuant to s 323 of the WIM Act due to Mr Asbury’s “pre-existing arthritis” plus an 8% WPI for the right upper extremity (shoulder), which the Medical Assessor found to be a “consequential injury”. No rateable WPI was assessed for Mr Asbury’s left lower extremity (knee) resulting from the December 2003 Injuries. Nor was any deduction made under s 323 in relation to the right shoulder. It is unclear why the Medical Assessor arrived at a combined total figure of 25% WPI for the December 2003 Injuries in circumstances where 18% + 8% = 26%. As to the s 323 deduction, the Medical Assessor reasoned as follows:

In my opinion the persistent symptom in the right knee is the result of injuries sustained at work in December 2003 and the underlying degenerative disease. I am of the opinion that the pre-existing degenerative disease is a component of the current impairment. I have deducted one tenth as outlined under 10a applying the provision of S323(2) as the extent of the deduction is difficult and costly to determine.

10. The plaintiff appealed the MAC. The medical dispute was referred to the second defendant, being the Appeal Panel constituted by one legal member and two medical members.

11. Both parties provided written submissions to the Appeal Panel. In brief, the plaintiff claimed that:

(a) the Medical Assessor erred in applying a 1/10th deduction under s 323; (b) the Medical Assessor erred in not providing adequate reasons why he considered it costly or difficult to determine the amount of an appropriate deduction under s 323 and failed to address whether a deduction of 1/10th was at odds with the evidence; and (c) it would not have been costly or difficult to determine the appropriate s 323 deduction.

12. In supplementary written submissions dated 8 November 2024, the plaintiff also drew attention to Basten AJ’s recent judgment in Virtue. The plaintiff submitted that any deductions under s 323 in relation to the right knee condition should logically follow through to any consequential impairments, “being the respondent worker’s consequential left shoulder condition [sic]”.

13. It may be interpolated here that it is difficult to understand the plaintiff’s reference in its supplementary written submissions to Mr Asbury’s “left shoulder condition” as a consequential injury. As noted at [7] above, the referral made no reference at all to Mr Asbury’s left shoulder condition; rather, his right shoulder condition was described as a consequential injury and was referred for assessment. It appears that there was a typographical error in the plaintiff’s submissions.

14. I will return below to summarise more fully relevant aspects of the parties’ submissions to the Appeal Panel.

15. I will now describe the unfortunate circumstances which saw the Appeal Panel provide no less than five revised statements of reasons for decision and medical assessment certificates relating to Mr Asbury’s claims.

16. In a decision dated 6 January 2025 (First Appeal Decision), the Appeal Panel found the Medical Assessor had failed to consider “all relevant evidence”. It revoked the MAC and issued a new MAC. Reflecting the fact that Mr Asbury had two claims for compensation, the new MAC contained a Table divided into two parts relating to the assessment of WPI in relation to the October and December 2003 Injuries respectively. That Table is now reproduced:

| Body Part | Date of injury | Chapter, page and paragraph number in NSW workers compensation guidelines | Chapter, page**, paragraph figure and** table numbers in AMA5 Guides | %WPI | % WPI deductions pursuant to S323 for pre-existing injury, condition or abnormality | Subtotal/s % WPI (after any deductions in column 6) | | Right knee | 21/10/03 (deemed) | Chapter 3 Pages 13-23 | Chapter 17 Pages 523 to 564 | 5% | Nil | 5% | | Left knee (consequential) | 21/10/03 (deemed) | Chapter 2 Pages 13-23 | Chapter 17 Pages 523 to 564 | 0% | Nil | 0% | | Right shoulder (consequential) | 21/10/03 (deemed | Chapter 2 Pages 10-12 | Chapter 16 Pages 433 to 521 | 8% | Nil | 8% | | Total % WPI (the Combined Table values of all sub-totals) | 5% |

| Body Part | Date of injury | Chapter, page and paragraph number in NSW workers compensation guidelines | Chapter, page**, paragraph** figure and table numbers in AMA5 Guides | %WPI | % WPI deductions pursuant to S323 for pre-existing injury, condition or abnormality | Subtotal/s % WPI (after any deductions in column 6) | | Right knee | 21/12/03 | Chapter 3 Pages 13-23 | Chapter 17 Pages 523 to 564 | 10% | N/A | 10% | | Left knee (consequential) | 22/12/03 | Chapter 2 Pages 13-23 | Chapter 17 Pages 523 to 564 | 0% | Nil | 0% | | Right shoulder (consequential) | 22/12/03 | Chapter 2 Pages 10-12 | Chapter 16 Pages 433 to 521 | 8% | N/A | 8% | | Total % WPI (the Combined Table values of all sub-totals) | 17% |

17. It is notable that, as is made clear by the entries in the sixth column in the Table, no deduction was made by the Appeal Panel under s 323 for any pre-existing injury, condition or abnormality. Moreover, in that particular column, the Appeal Panel inserted either “Nil” or “N/A” in respect of each of the body parts the subject of the referral. It is unclear whether or not the Appeal Panel considered those expressions to mean the same or different things.

18. Both the plaintiff and Mr Asbury were agreed that the First Appeal Decision should be amended because it contained the following two obvious errors:

(a) Notwithstanding the Appeal Panel’s determination as reflected in its reasons dated 6 January 2025, that one-quarter of the 20% WPI of the right knee related to the October 2003 Injuries and three-quarters to the second injury dated December 2003, the Table in the Appeal Decision attributed 5% WPI to the October 2003 Injuries and 10% to the December 2003 Injuries. (b) In the Table, an assessed impairment of 8% WPI in relation to the right shoulder (consequential) appeared as a sub-total in respect of both the October 2003 Injuries and the December 2003 Injuries but was then only included in the total WPI for the December 2003 Injuries.

19. In an email dated 23 January 2025 to the PIC, the plaintiff’s solicitor noted these two errors and also drew attention to the fact that at [48] of the reasons concerning the First Appeal Decision, the Appeal Panel said that, there being no dispute with respect to the right shoulder, the Medical Assessor’s assessment of the right shoulder should stand. The solicitor added that the Medical Assessor had assessed the right shoulder impairment only in respect of the December 2003 Injuries. Accordingly, the solicitor submitted that the inclusion of the right shoulder assessment for the October 2003 Injuries in the Table in the MAC dated 6 January 2025 might be a typographical error and should be deleted.

20. By an email dated 28 January 2025, Mr Asbury’s solicitor confirmed that the assessment for the right knee injury dated December 2003 should be increased from 10% to 15%, “causing the combined assessment for that injury to be 22%”. The solicitor also confirmed that that assessment for the right shoulder should be removed from the Table for the October 2003 Injuries.

21. The Appeal Panel then issued several amended decisions in a continuing attempt to cure what were agreed by the parties to be obvious errors.

22. On 4 February 2025, the Appeal Panel issued an amended MAC and an amended statement of reasons (Second Appeal Decision). On the same day, the parties’ solicitors emailed the PIC, noting that the amended assessment omitted an assessment for the right shoulder and was also in error in adding together WPI attributable to two dates of injury, i.e. the October 2003 and December 2003 Injuries.

23. By a formal direction dated 6 February 2025, the PIC remitted to the President a request that a replacement MAC be issued in circumstances where the parties agreed, having regard to the terms of the referral and the Appeal Panel’s statement of reasons, that there were obvious errors in the amended MAC dated 4 February 2025. The Direction contained a notation that the parties agreed that the MAC should be amended so as to read:

(i) Date of injury: 21 October 2003 (deemed):

| Right lower extremity (knee) | 5% | | Left lower knee extremity (knee) | 0% | | Right upper extremity (shoulder) | 0% | | TOTAL | 5% WPI |

(ii) Date of injury: 22 December 2003:

| Right lower extremity (knee) | 15% | | Left lower knee extremity (knee) | 0% | | Right upper extremity (shoulder) | 8% | | TOTAL | 22% WPI |

24. The Appeal Panel published an amended statement of reasons and an amended MAC on 17 April 2025 (Third Appeal Decision). Later that day, the plaintiff’s solicitor emailed the PIC drawing attention to the fact that the Third Appeal Decision was erroneously dated 4 February 2025. On 22 April 2025, the PIC informed the parties that the date had been corrected to 17 April 2025.

25. But that was not the end of the matter. Once again, the amended MAC contained no reference to any WPI assessment in respect of Mr Asbury’s right shoulder, an omission which was picked up by the PIC. The parties then asked that the omission be rectified in accordance with the Direction dated 6 February 2025. The relevant part of the amended MAC is as follows (Fourth Appeal Decision):

| Body Part | Date of injury | Chapter, page and paragraph number in NSW workers compensation guidelines | Chapter, page**, paragraph** figure and table numbers in AMA5 Guides | %WPI | % WPI deductions pursuant to S323 for pre-existing injury, condition or abnormality | Subtotal/s % WPI (after any deductions in column 6) | | Right knee | 21/10/03 (deemed) | Chapter 3 Pages 13-23 | Chapter 17 Pages 523 to 564 | 5% | Nil | 5% | | Right knee | 22/12 /03 | Chapter 2 Pages 10-12 | Chapter 16 Pages 433 to 521 | 15% | Nil | 15% | | Left knee (consequential) | 22/12/03 | Chapter 2 Pages 13-23 | Chapter 17 Pages 523 to 564 | 0% | N/A | 0% | | Total % WPI (the Combined Table values of all sub-totals) | 20% |

26. On 19 May 2025, the Appeal Panel published yet another statement of reasons and an amended MAC, both bearing that date though referring to the date of decision as 4 February 2025. These documents constitute the Final Decision which is the subject of these proceedings.

27. The final MAC issued by the Appeal Panel on 19 May 2025 is as follows:

| Body Part | Date of injury | Chapter, page and paragraph number in NSW workers compensation guidelines | Chapter, page**, paragraph** figure and table numbers in AMA5 Guides | %WPI | % WPI deductions pursuant to S323 for pre-existing injury, condition or abnormality | Subtotal/s % WPI (after any deductions in column 6) | | Right lower extremity (knee) | 21/10/03 (deemed) | Chapter 3 Pages 13-23 | Chapter 17 Pages 523 to 564 | 5% | Nil | 5% | | Left lower extremity (knee) | 22/12 /03 | Chapter 2 Pages 10-12 | Chapter 16 Pages 433 to 521 | 0% | Nil | 0% | | Right upper extremity (shoulder) Total | 0% | 0% 5% |

| Body Part | Date of injury | Chapter, page and paragraph number in NSW workers compensation guidelines | Chapter, page**, paragraph** figure and table numbers in AMA5 Guides | %WPI | % WPI deductions pursuant to S323 for pre-existing injury, condition or abnormality | Subtotal/s % WPI (after any deductions in column 6) | | Right lower extremity (knee) | 22/12/03 | Chapter 3 Pages 13-23 | Chapter 17 Pages 523 to 564 | 15% | N/A | 15% | | Left lower extremity (knee) Right upper extremity (shoulder) | 22/12 /03 | | | 0% 8% | | 0% 8% | | Total % WPI (the Combined Table values of all sub-totals) | 22% |

28. It is unclear why the Table contains two separate references to the WPI assessment for “left lower extremity (knee)” dated 22/12/03 in both parts of the Table. Nor is it clear why the wording in columns three and four differs in respect of those two particular assessments. The Appeal Panel’s reasons dated 19 May 2025 cast no light on these anomalies. Assuming that the first part of the Table was intended to relate only to the October 2003 Injuries, it may be that the date in respect of “Left lower extremity (knee)” in that part of the Table should be 21/10/03 and not 22/12/03. I did not understand the plaintiff to contend that these particular anomalies or the earlier errors and omissions were relevant to its judicial review case, but they do reflect adversely on the quality of the Appeal Panel’s documentation and deliberative processes.

The reasons for the Final Decision summarised

29. As noted above, in the Final Decision, Mr Asbury was assessed as having a 5% WPI as a result of the October 2003 Injuries. This figure related solely to Mr Asbury’s right lower extremity (knee). As is made clear in the first part of the Table at [27] above, the Appeal Panel found that the consequential left lower extremity (knee) and right upper extremity (shoulder) did not result in any WPI. No WPI deduction was made pursuant to s 323 of the WIM Act for any pre-existing injury, condition or abnormality, as is made clear by the use of the word “Nil” in the sixth column of the first part of the Table.

30. The December 2003 Injuries were assessed as giving rise to a 15% WPI for the right lower extremity (knee) and 8% WPI for the right upper extremity (shoulder). The Appeal Panel determined that the left lower extremity (knee) attracted a 0% WPI. As is evident from the sixth column of the second part of the Table, the Appeal Panel determined that no deduction should be made under s 323 for pre-existing injury, condition or abnormality in respect of Mr Asbury’s right lower extremity and the Appeal Panel inserted the expression “N/A” in the relevant column in the second part of the Table. The Appeal Panel attributed a figure of 0% WPI to Mr Asbury’s left lower extremity (knee) and no figure was provided for any WPI deduction under s 323 in respect of that body part. It is also evident from the sixth column of the second part of the Table that the Appeal Panel made no deduction under s 323 for pre-existing injury, condition or abnormality in respect of the right upper extremity (shoulder).

31. The Table at [27] above states that the “Combined Table values” of all the sub-totals produces a total WPI of 22%. It is difficult to see how that figure is arithmetically correct when the sub-totals are 5%, 15% and 8%, totalling 28%. Again, however, the plaintiff did not suggest this anomaly was relevant to its judicial review case.

32. In its reasons for the Final Decision, the Appeal Panel summarised the plaintiff’s claim that the Medical Assessor had erred in his application of s 323, failed to consider available evidence and failed to provide adequate reasons. It also noted the plaintiff’s supplementary submissions that the Medical Assessor erred in failing to have regard to the matters raised in Basten AJ’s judgment in Virtue concerning a deduction under s 323 flowing through to consequential injuries.

33. At [16] to [24] of the reasons, the Appeal Panel summarised at some length the Medical Assessor’s decision, described the results of the Medical Assessor’s examination of Mr Asbury, referred to the radiological and other material and outlined what Mr Asbury told the Medical Assessor about his conditions. It noted that Mr Asbury had told the Medical Assessor that he had a right knee reconstruction in the early 1990s, for which he had fully recovered and had had no problems with that knee.

34. At [25] of its reasons, the Appeal Panel gave a detailed summary of the plaintiff’s written submissions, including evidence before the Medical Assessor regarding Mr Asbury’s pre-existing injury and conditions affecting his right knee. The Appeal Panel referred to the plaintiff’s claim that the Medical Assessor did not record any of the findings of Dr Verheul (Mr Asbury’s treating surgeon) in his reports dated 15 January 2004, 9 February 2004, 31 March 2004 and 14 September 2005 and subsequent reports in which Dr Verheul said that ultimately, because of the ongoing degenerative osteoarthritis, Mr Asbury would require a total replacement for his right knee, but that this surgery should be deferred for as long as possible given Mr Asbury’s age. The Appeal Panel noted the plaintiff’s claim that the Medical Assessor had failed to take a complete history of the 13 May 1989 injury, the 30 August 1996 injury, the decision of the Compensation Court dated 23 February 2000 in respect of the 30 August 1996 injury or a Medical Assessment Certificate dated 27 October 2005 when Medical Assessor Dr Drew Dixon recorded that Mr Asbury had fractured his right ankle in a motor vehicle accident in 1989, as well as injuring his left knee and the AC joint of his left shoulder. Dr Dixon also noted that Mr Asbury had injured his right knee in 1997 which resulted in his right knee being reconstructed on 30 April 1997. In those circumstances, Dr Dixon applied a 50% deduction for pre-existing arthritis and cruciate reconstruction, producing a total 7% WPI.

35. The Appeal Panel noted the plaintiff’s submission that the Medical Assessor did not address the fact that Dr Dixon had made a deduction of 50% in the 2005 MAC or explain why a different approach should be taken. It noted that the plaintiff complained that the Medical Assessor did not address opinions by Drs Hopcroft and Panjratan, who both considered that a 50% deduction was appropriate in light of the 2005 MAC. Reference was made to the earliest medical report of Professor YAE Ghabrial who apportioned 15% of Mr Asbury’s impairment to the 1997 injury and 50% to the October 2003 Injuries. The Appeal Panel also acknowledged that the Medical Assessor had “referenced the reports of Dr Powell who deducted one third for pre-existing conditions”.

36. Finally, the Appeal Panel noted the plaintiff’s claim, relying on Virtue, that any deductions made under s 323 for the right knee condition should logically flow through to any consequential impairment, being Mr Asbury’s “consequential left shoulder condition”. The Appeal Panel appears to have appreciated that this submission by the plaintiff was in error because the relevant consequential condition related to Mr Asbury’s right shoulder and not his left shoulder – see at [13] above. The Appeal Panel also referred to the fact that the plaintiff noted that the Medical Assessor had assessed no impairment for the consequential left-knee condition.

37. At [27] of its reasons, the Appeal Panel provided a brief summary of Mr Asbury’s submissions, including his submission that Basten AJ’s observations in Virtue were only obiter. It also noted his submission that any deduction required by s 323 “is to the specific impairment assessed pertaining to the specific injury” and that it was inconsistent with s 323 to deduct an impairment in respect of one body part simply because a deduction was to be made in respect of another body part. This inconsistency was said to relate to the fact that s 323 “is focused upon the impairment to the specific injury or impairment and requires consideration of medical evidence pertaining to a specific injury or impairment”.

38. From [28] to [53] of its reasons, the Appeal Panel explained how it had arrived at the Final Decision. In brief:

(a) It accepted Mr Asbury’s submission regarding Virtue (at [28]). (b) It noted that the Medical Assessor had assessed all Mr Asbury’s impairments as resulting from the 22 December 2003 Injury, and he had found no impairment of the left knee as a consequential injury and made a one-tenth deduction to arrive at a figure of 18% WPI, to which was added 8% WPI for the consequential injury to the right shoulder (at [29]-[30]). (c) It noted that the Medical Assessor’s decision relied in part on the fact that Mr Asbury had had a right knee reconstruction in the early 1990s from which he had fully recovered and played touch football, exercised and did boxing without any problems (at [31]). (d) The Appeal Panel also noted that the Medical Assessor had recognised that Professor Ghabrial had not made any deductions for any pre-existing condition, but Dr Powell had made a one-third deduction (at [32]). The Appeal Panel added that this was not “strictly correct” because in Dr Ghabrial’s earliest report, he had considered that the impairment should be apportioned, with 50% to the 1997 injury and 50% to the October 2003 Injuries. (e) It accepted the plaintiff’s submission that the Medical Assessor had not referred to several medical reports, particularly those of Dr Verheul who had noted in a report dated 31 March 2004 that it was “predictable that Mr Ashbury’s [sic] osteoarthritic process is progressive” and that ultimately a knee replacement would be required at some stage (at [34]). (f) It also noted Dr Verheul’s report dated 14 September 2005 where he stated that the only real alternative was a total knee replacement but suggested that this should be done when Mr Asbury was older (at [37]). (g) It noted again that Dr Dixon had made a 50% deduction in WPI for Mr Asbury’s previous injury and the reconstruction of his right knee in 1998 (at [38]). (h) It agreed with the plaintiff’s submission that there was “significant evidence before the [Medical Assessor] confirming that Mr Asbury had severe degenerative changes in his right knee prior to his more recent injuries” (at [39]). (i) It agreed with the Medical Assessor that the injury sustained in October 2003 “was relatively minor” and Mr Asbury “fully recovered and …returned to normal duties and had no problems with the knee until 22 December 2003” (at [43]-[44]). (j) It found that the injury suffered by Mr Asbury in December 2003 “was clearly more significant”. The Appeal Panel adopted the Medical Assessor’s summary of the nature of that injury and the circumstances in which it was sustained (at [45]). (k) It agreed that the Medical Assessor was “correct in applying all the impairment to the second injury” (at [46]). (l) The Appeal Panel then added that the “nature of this claim and the terms of the referral” required the Appeal Panel “to apportion between the two injuries, and then consider the application of s323 to the injury to the right knee” (at [49]). (It may be noted that a copy of the formal referral to the Appeal Panel was not included in the Court Book before me). (m) It also agreed that the Medical Assessor failed to take a complete history regarding the injuries in 1989 and 1996, nor did the Medical Assessor take into account the decision of the Compensation Court or the 2005 MAC (at [40]). (n) Having found that the Medical Assessor had failed to consider the reports by Drs Dixon and Verheul, the Appeal Panel said that its task was “to apportion the impairment between the two injuries” (at [41] and [42]). (o) It stated that the Medical Assessor was correct in applying all the WPI to the December 2003 Injuries (at [46]), in circumstances where the Appeal Panel had found that the October 2003 Injuries were “relatively minor” (at [43]) and described the December 2003 Injuries as “clearly more significant” (at [45]). (p) The Appeal Panel said that as “a starting point”, the Medical Assessor had “assessed 20% WPI for a fair result following the right total knee replacement which is the correct figure” (at [50]).

39. It is desirable to set out the following paragraphs of the Appeal Panel’s reasons as they provide the focus for the plaintiff’s judicial review challenge (emphasis added):

46. We agree that the [Medical Assessor] was correct in applying all the impairment to the second injury.

47. The [Medical Assessor] assessed 0% WPl in respect of the consequential injury to the left knee and we do not consider that the [Medical Assessor] has erred in his assessment. Neither the appellant nor the respondent made any submissions regarding the assessment of the left knee so that it should stand.

48. With respect to the right shoulder, this was accepted as being a consequential injury and again, neither party has challenged the assessment of 8% WPl. We accept it and it should stand.

49. Having said that, the nature of this claim and the terms of the referral require us to apportion between the two injuries, and then consider the application of s323 to the injury to the right knee.

50. As a starting point, as noted earlier, the [Medical Assessor] assessed 20% WPI for a fair result following the right total knee replacement which is the correct figure.

51. Having carefully considered the whole of the evidence, and the numerous medical reports noting the advanced degenerative changes in the right knee, we consider that 1/4 of the impairment relates to the first injury and 3/4 to the second injury.

52. The total impairments, the apportionment and the respective deductions are noted in the Table attached to our decision.

53. For these reasons, the Appeal Panel has determined that the MAC issued on 3 October 2004 12 December [sic] should be revoked, and a new MAC should be issued. The new certificate is attached to this statement of reasons.

40. The reference in [53] of the Appeal Panel’s reasons to “3 October 2004 12 December” is plainly in error. It should read “3 October 2024”. Again, this reflects very poorly on the quality of the Appeal Panel’s documentation and its attention to detail.

41. The Appeal Panel acknowledged at [49] of its reasons that it needed to consider the application of s 323 to the right knee injury (after apportioning the degree of impairment attributable to the October and December 2003 Injuries). Ultimately, however, no deduction was made under s 323 in respect of the right knee injury (or any of the consequential injuries). The Appeal Panel provided no explicit explanation for not making any s 323 deduction, notwithstanding that the Medical Assessor had applied a 10% deduction in respect of the right knee injury. I shall explain below, however, why I consider that the Appeal Panel’s reasoning on this matter may be inferred from relevant passages towards the end of its final statement of reasons.

Consideration and determination

42. Before addressing each of the five grounds of judicial review raised in the summons, it is convenient to identify the primary relevant legislative provisions.

43. Part 7 of Ch 7 of the WIM Act contains provisions relating to the referral, and assessment of, “medical disputes” (as defined in s 319), as well as appeals from such assessments.

44. Section 322 of the WIM Act relevantly provides:

Assessment of impairment

(1) The assessment of the degree of permanent impairment of an injured worker for the purposes of the Workers Compensation Acts is to be made in accordance with Workers Compensation Guidelines (as in force at the time the assessment is made) issued for that purpose.

(2) Impairments that result from the same injury are to be assessed together to assess the degree of permanent impairment of the injured worker.

(3) Impairments that result from more than one injury arising out of the same incident are to be assessed together to assess the degree of permanent impairment of the injured worker.

…

45. Section 323 relevantly provides:

Deduction for previous injury or pre-existing condition or abnormality

(1) In assessing the degree of permanent impairment resulting from an injury, there is to be a deduction for any proportion of the impairment that is due to any previous injury (whether or not it is an injury for which compensation has been paid or is payable under Division 4 of Part 3 of the 1987 Act) or that is due to any pre-existing condition or abnormality.

(2) If the extent of a deduction under this section (or a part of it) will be difficult or costly to determine (because, for example, of the absence of medical evidence), it is to be assumed (for the purpose of avoiding disputation) that the deduction (or the relevant part of it) is 10% of the impairment, unless this assumption is at odds with the available evidence.

Note.

So if the degree of permanent impairment is assessed as 30% and subsection (2) operates to require a 10% reduction in that impairment to be assumed, the degree of permanent impairment is reduced from 30% to 27% (a reduction of 10%).

(3) The reference in subsection (2) to medical evidence is a reference to medical evidence accepted or preferred by the medical assessor in connection with the medical assessment of the matter.

(4) The Workers Compensation Guidelines may make provision for or with respect to the determination of the deduction required by this section.

…

46. The Workers Compensation Guidelines referred to in s 322(1) and s 323(4) are those issued under s 376 of the WIM Act, being the NSW Workers Compensation Guidelines for the Evaluation of Permanent Impairment, 4th ed, 1 March 2021 (Guidelines). The Guides to the Evaluation of Permanent Impairment issued by the American Medical Association are also relevant.

Ground 1 – failure to make a s 323 deduction

47. It is uncontroversial that the material before the Appeal Panel demonstrated that the plaintiff had a long-documented history of problems with his right knee, including osteoarthritis, well before the injuries he sustained in October and December 2003.

48. The plaintiff contends, relying on principles established in cases such as Cole v Wenaline Pty Ltd [2010] NSWSC 78; Elcheikh v Diamond Formwork (NSW) Pty Ltd (in liq*)* [2013] NSWSC 365 and Southwell v Qantas Airways Ltd [2024] NSWSC 497, that the Appeal Panel was required under s 323 to determine the extent of the resulting impairment caused by the workplace injuries and whether any pre-existing condition contributed to the impairment. Those authorities also establish that, where it is found that a pre-existing condition contributed to the impairment, it then becomes necessary to determine what proportion of the impairment was due to the pre-existing condition.

49. The plaintiff’s claims in support of Ground 1 are reflected in the following paragraphs of its outline of written submissions:

To use the language of s323 of the WIM Act and approach mandated by the authorities above (focus being on the first two steps):

a. The WPI impairment assessed here was flowing from the outcome of a total knee replacement, in respect of both the October 2003 Injuries and the December 2003 Injuries.

b. The actual consequences of the pre-existing condition (arthritic changes in the first defendant’s right knee/prior surgery), was that a total knee replacement would be required.

Informed by the above, this is plainly a case where a deduction under s323(1) of the WIM Act should have been made. That is because the impairment flowing from the knee (in respect of the October 2003 Injuries and the December 2003 Injuries) pertained to a total knee replacement, with that impairment also contributed to by the prior knee condition (reiterating a knee replacement was previously indicated). While the October 2003 Injuries and the December 2003 Injuries may have brought the need for that surgery forward, it cannot be ignored that some impairment flows from the prior condition.

The extent of that deduction was then to be determined, including by reference to s323(2) of the WIM Act if that applied. Again, this did not occur when it should have.

50. Mr Jones of counsel (who appeared for the plaintiff) expressed the essence of the plaintiff’s complaint more pithily:

… if there is a contribution to the impairment outside of the October '03 and December '03 injuries that should be reduced of those primary injuries and any consequential condition flowing from those.

[If it] were otherwise, it would have the result of meaning the full impairment for the right shoulder, is sheeted home to the employer without any corresponding reduction which had been made to the primary injury.

51. For the following reasons I reject Ground 1.

52. The task of a medical assessor under s 323 was described by Schmidt J in Cole at [38]:

What s 323 required, however, was that the evidence be considered, so that it could be determined, firstly, what the level of impairment after the second injury was. Secondly, whether a proportion of that impairment was due to the first injury. Thirdly, what that proportion was. Undoubtedly in undertaking this exercise, the medical members of an Appeal Panel must utilise their medical judgment, knowledge and experience. Nevertheless, all stages of the statutory exercise must be taken in the light of the evidence and without the making of assumptions not provided for by the section.

53. Earlier in the reasons for judgment in Cole, her Honour made the following observations regarding s 323 (emphasis added):

29. … The section is directed to a situation where there is a pre-existing injury, pre-existing condition or abnormality. For a deduction to be made from what has been assessed to have been the level of impairment which resulted from the later injury in question, a conclusion is required, on the evidence, that the pre-existing injury, pre-existing condition or abnormality caused or contributed to that impairment.

30. Section 323 does not permit that assessment to be made on the basis of an assumption or hypothesis, that once a particular injury has occurred, it will always, ‘irrespective of outcome’, contribute to the impairment flowing from any subsequent injury. The assessment must have regard to the evidence as to the actual consequences of the earlier injury, pre-existing condition or abnormality. The extent that the later impairment was due to the earlier injury, pre-existing condition or abnormality must be determined. The only exception is that provided for in s 323(2), where the required deduction ‘will be difficult or costly to determine (because, for example, of the absence of medical evidence)’. In that case, an assumption is provided for, namely that the deduction ‘is 10% of the impairment’. Even then, that assumption is displaced, if it is at odds with the available evidence.

…

34. … Section 323 requires that a conclusion be reached as to whether or not any proportion of permanent impairment assessed resulted from an earlier injury, pre-existing condition or abnormality. In a case such as this, that conclusion must be reached on the evidence led as to the actual consequences of the earlier and later injuries, unless the assumption provided in s 323(2) applies.

54. This approach was endorsed and explained by Campbell J in Ryder v Sundance Bakehouse [2015] NSWSC 526 at [45] (emphasis added):

What s 323 requires is an inquiry into whether there are other causes, (previous injury, or pre-existing abnormality), of an impairment caused by a work injury. A proportion of the impairment would be due to the pre-existing abnormality (even if that proportion cannot be precisely identified without difficulty or expense) only if it can be said that the pre-existing abnormality made a difference to the outcome in terms of the degree of impairment resulting from the work injury. If there is no difference in outcome, that is to say, if the degree of impairment is not greater than it would otherwise have been as a result of the injury, it is impossible to say that a proportion of it is due to the pre-existing abnormality. To put it another way, the Panel must be satisfied that but for the pre-existing abnormality, the degree of impairment resulting from the work injury would not have been as great.

55. Finally, it is desirable to note the following observations by Wright J in Southwell at [49]-[50] which also approve the approach in Cole:

49. On its terms, however, s 323(2) does not apply if it has not been determined that a deduction is to be made under subs (1) because a part or portion of the level of impairment suffered was due to the pre-existing condition. Subsection (2) relates only to “the extent of a deduction under this section” not to whether such a deduction is required. As Schmidt J held, in effect, in Cole v Wenaline Pty Ltd [2010] NSWSC 78 (Cole) at [30] and [31], s 323(1) does not permit the assessment of whether a deduction is required to be made on the basis of an assumption or hypothesis, that once there is found to be a particular pre-existing condition, it will always, “irrespective of outcome”, contribute to the impairment flowing from any subsequent injury. Rather, the assessment of whether a deduction is required must have regard to the evidence as to the actual consequences of the pre-existing condition and whether any proportion of the permanent impairment present after the workplace injury was due to the pre-existing condition.

50. Thus, it has been held, in cases such as Elcheikh v Diamond Formwork (NSW) Pty Ltd (in liq) [2013] NSWSC 365 at [126] (Schmidt J) and Secretary, Department of Communities and Justice v Lewandowski [2023] NSWSC 334 at [52] (Griffith AJ), that what must be determined under s 323 involves, at least, three enquiries:

• Firstly, what the extent of the resulting impairment is.

• Secondly, whether the pre-existing condition contributed to the impairment.

• Thirdly, if it did, what proportion of the impairment was due to the pre-existing condition.”

56. In the light of those principles, I do not accept the plaintiff’s claim that the Appeal Panel erred in not making a deduction under s 323.

57. It is evident from the Appeal Panel’s final statement of reasons that it had regard to the medical evidence which indicated that Mr Asbury had sustained injuries to, and had severe degenerative changes in, his right knee before the injuries in October and December 2003. However, as is made clear in cases such as Cole and Ryder, the fact that there is a pre-existing injury or condition does not necessarily mean that it will always contribute to the impairment flowing from a subsequent workplace injury. The pre-existing condition must make a difference to the ultimate outcome in terms of the degree of impairment resulting from the workplace injury. As Campbell J explained in Ryder at [45], for there to be a deduction under s 323 relating to Mr Asbury’s pre-existing degeneration in his right knee, the Appeal Panel had to be satisfied that, but for that pre-existing condition, the degree of impairment resulting from his workplace injuries suffered in October and December 2003 would not have been as great.

58. In my view, although it is regrettable that the Appeal Panel did not elaborate upon its reasons, I consider that it understood, and correctly applied, s 323 of the Act, as explained in cases such as Cole, Ryder and Southwell. It is plain from [39] of the Appeal Panel’s reasons that it was well aware of the evidence that Mr Asbury had severe degenerative changes in his right knee prior to the October and December 2003 Injuries. Indeed, the Appeal Panel described the material on this pre-existing condition as amounting to “significant evidence before the [Medical Assessor]”. However, the Appeal Panel answered the second of the three steps posed in Cole (i.e. whether a proportion of the level of impairment after the December 2003 Injuries was due to the degenerative changes in his right knee which pre-existed both the October and December 2003 Injuries) in the negative. The Appeal Panel stated at [51] that it had carefully considered the whole of the evidence “and the numerous medical reports noting the advanced degenerative changes in the right knee” before concluding that 25% of Mr Asbury’s WPI related to the October 2003 Injuries and the remainder to the December 2003 Injuries. It is necessarily implicit in those findings that the Appeal Panel concluded that none of Mr Asbury’s WPI was attributable to the pre-existing degenerative changes in his right knee.

59. There was some evidence to support that conclusion. For example, the medical evidence included several reports by Professor Ghabrial, including two reports dated 23 September 2020 and 18 October 2023. In the first of those reports, Professor Ghabrial provided WPI assessments in respect of Mr Asbury’s right knee, and also his left knee and lumbar spine. He assessed a WPI for the right knee at 21% (20% representing a “fair result of right total knee replacement” as a result of the October and December 2003 Injuries and a WPI of 1% for a scar to the right knee).

60. In his report dated 18 October 2023, Professor Ghabrial assessed a 20% WPI for the impairment of the right knee resulting from the October and December 2003 Injuries. He noted that Mr Asbury had had previous problems with his right knee, but since his reconstruction procedure to that knee in the 1990s he had “recovered fully and had no problems resuming normal activities”. Professor Ghabrial also assessed WPI in respect of other body parts, including the left knee, lumbar spine and right shoulder. Significantly, Professor Ghabrial expressly noted: “No deduction is needed”. The Appeal Panel in the present proceeding came to the same conclusion as is reflected in the Table. It is well to recall that the Appeal Panel said at [51] that it had “carefully considered the whole of the evidence and the numerous medical reports noting the advanced degenerative changes in the right knee”. I see no reason to doubt the correctness of that statement.

61. There undoubtedly was evidence which addressed the degenerative changes in Mr Asbury’s right knee and the likely need for him to have a total knee replacement (see, for example, at [34]-[35] above, where some of that evidence is summarised, particularly that of Dr Verheul). Perhaps the high point of Dr Verheul’s evidence on the issue appears in his report dated 3 April 2006, which report was before the Appeal Panel but not expressly referred to by it. In that report Dr Verheul said:

The diagnosis in Mr Asbury’s case is osteoarthritis and the prognosis is gradual deterioration over the course of time until total knee replacement surgery is indicated. The reported nature of the injury was a result of stair climbing under load and also a hyper-flexion injury. Certainly the hyper-flexion injury could have delaminated further areas of cartilage to precipitating symptoms. Mr Asbury would have had problems with his knee nonetheless in the future despite a work place injury. I believe that Mr Asbury is genuine in his complaint and certainly the level of his symptoms is consistent with the arthroscopic findings of his knee.

62. It is notable, however, that this evidence predates the total right knee replacement which Mr Asbury had in 2013.

63. The Appeal Panel did not refer specifically to all of the medical evidence before it concerning Mr Asbury’s pre-existing condition but, as noted above, it said that it had carefully considered all the evidence including the numerous medical reports which noted the degenerative changes in Mr Asbury’s right knee. Ultimately, however, the Appeal Panel was required to apply its own clinical judgment in making relevant findings concerning the effect of pre-existing impairments on any compensable injury (see the Guidelines at [1.6(b)], [1.27] and [1.28]). Its findings concerning which if any of Mr Asbury’s pre-existing conditions contributed to his impairment are findings of fact (see Matthew Hall Pty Ltd v Smart [2000] NSWCA 284; 21 NSWCCR 34 at [33] per Giles JA (Mason P and Powell JA agreeing)).

64. Moreover, while accepting that there were conflicting medical reports before it, it was not the Appeal Panel’s task to choose between the competing medical evidence; rather it had to apply its own medical experience and expertise (see Wingfoot Australia Partners Pty Ltd v Kocak (2013) 252 CLR 480; [2013] HCA 43 at [47], which is set out at [66] below).

65. In the upshot, it was unnecessary for the Appeal Panel to address the third step identified in Cole, namely what is the proportion of the impairment resulting from any pre-existing condition for which there should be a deduction under s 323(1) because the Appeal Panel considered that Mr Asbury’s pre-existing condition did not contribute to his impairment. As the third step did not arise, the plaintiff’s reliance on Virtue is also misconceived.

Ground 2 – failure to provide adequate reasons concerning s 323

66. It is common ground that the Appeal Panel had an implied statutory duty to give reasons and that the reasons must “explain the actual path of reasoning by which the [decision-maker] in fact arrived at [its decision]” (see Wingfoot at [55]). It is also well to bear in mind what the High Court said in Wingfoot at [47] regarding the function of a Medical Panel under different legislation, but which observations apply equally to the Appeal Panel here (footnotes omitted):

The function of a Medical Panel is to form and to give its own opinion on the medical question referred for its opinion. In performing that function, the Medical Panel is doubtless obliged to observe procedural fairness, so as to give an opportunity for parties to the underlying question or matter who will be affected by the opinion to supply the Medical Panel with material which may be relevant to the formation of the opinion and to make submissions to the Medical Panel on the basis of that material. The material supplied may include the opinions of other medical practitioners, and submissions to the Medical Panel may seek to persuade the Medical Panel to adopt reasoning or conclusions expressed in those opinions. The Medical Panel may choose in a particular case to place weight on a medical opinion supplied to it in forming and giving its own opinion. It goes too far, however, to conceive of the function of the Panel as being either to decide a dispute or to make up its mind by reference to competing contentions or competing medical opinions. The function of a Medical Panel is neither arbitral nor adjudicative: it is neither to choose between competing arguments, nor to opine on the correctness of other opinions on that medical question. The function is in every case to form and to give its own opinion on the medical question referred to it by applying its own medical experience and its own medical expertise.

67. The adequacy of the Appeal Panel’s reasons should be viewed in the particular context of the case, which necessarily involves attention being given to the relevant history of the proceeding, including the content of the parties’ submissions in identifying the relevant issues requiring determination by the Appeal Panel. The reasons “need not be extensive” or “provide a detailed explanation of the way in which the relevant criteria [were] applied by medical specialists” (see Fullford v Maccas Ferry Services Pty Ltd [2016] NSWSC 1161 at [43] per Harrison J).

68. I well understand why the plaintiff is so critical of the Appeal Panel’s reasons. I have highlighted above an embarrassing number of errors, anomalies or omissions in the various iterations of those reasons. These matters reflect adversely on the Appeal Panel’s attention to detail and would provide a promising starting point for a merits review of the Final Decision if such a review was available. But the proceedings before me are not in the nature of a merits review. The Court is obliged to observe and apply the well-established distinction between judicial review and review on the merits.

69. Ground 2 of the summons targets the adequacy of the Appeal Panel’s reasons concerning its determination not to make any deduction under s 323. Ideally, the Appeal Panel should have explained at greater length why no deduction was made under that provision, but that is not to say that its reasons are inadequate in law.

70. I have set out above how, fairly read, the Appeal Panel’s reasons at [46], [49] and [51]-[52] in particular adequately reveal that the basis for the Appeal Panel’s determination regarding s 323 related to its finding that the pre-existing degenerative changes in Mr Asbury’s right knee did not contribute to the impairment relating to the October and December 2003 Injuries, with the consequence that no deduction should be made under s 323 concerning those matters.

Ground 3 – failure to respond to a clearly articulated argument

71. This ground relates to the plaintiff’s claims that the Appeal Panel failed to provide reasons explaining why:

(a) it did not accept the plaintiff’s reliance on Virtue; (b) s 323 did not apply as contemplated in Virtue; and (c) Mr Asbury’s submissions concerning Virtue were accepted or correct.

72. For the following reasons, I do not consider that the Appeal Panel overlooked or failed to address the plaintiff’s arguments concerning Virtue and the making of a deduction under s 323. The argument was identified in various parts of the Appeal Panel’s statement of reasons. In the “Discussion” section of the reasons, the Appeal Panel recorded its acceptance of Mr Asbury’s “submission” concerning Virtue and said that it “d[id] not propose to consider it further in respect of this matter” (at [28]).

73. While it is not clear from the Appeal Panel’s reasons which of Mr Asbury’s particular submissions regarding Virtue were accepted, that lack of clarity is not material. That is because the plaintiff’s argument relying on Virtue did not have to be resolved by the Appeal Panel. This necessarily flowed from the Appeal Panel’s findings that no deduction should be made under s 323 in respect of either the October or December 2003 Injuries, including the consequential injury to his right shoulder. Accordingly, it was not necessary for the Appeal Panel to form a view about whether any deduction should flow through to any consequential conditions.

Ground 4 – error in assessing WPI for October 2003 injuries

74. By this ground, the plaintiff contends that the Appeal Panel made an irrational or illogical finding of fact in its assessment of Mr Asbury’s WPI referable to the injuries that he sustained in October 2003. Its argument, as set out in its written submissions, is as follows (emphasis in original):

56 The second defendant found in the Final Decision that the October 2003 Injuries were ‘relatively minor’, at [43]. In contrast, the December 2003 Injuries were said to be ‘clearly more significant’, at [45].

57 Flowing from that, the second defendant found in the Final Decision that it was correct for the [Medical Assessor] to have applied ‘all the impairment to the second injury [being the December 2003 Injuries]’, at [46].

58 Contrary to what it found, the second defendant took the illogical step of assessing a 5% WPI of the first defendant’s right lower extremity (knee) as referable to the October 2003 Injuries.

59 That is an illogical approach and so an error of law.

75. In oral address, Mr Jones submitted that it was irrational of the Appeal Panel to state at [46] of its reasons that the Medical Assessor was correct in applying all the impairment to the December 2003 Injuries in circumstances where it then proceeded to attribute a 5% WPI to the right knee attributable to the October 2003 Injuries.

76. Although the parties acknowledged that the Court of Appeal’s decision in Azzopardi v Tasman UEB Industries Ltd (1985) 4 NSWLR 139 stands for the proposition that a finding of fact which could be characterised as “perverse” or “illogical” does not raise a point of law for the purposes of a statutory appeal, it was common ground that, for the purposes of judicial review for jurisdictional error or error of law on the face of the record, review is available where a decision is based on illogical, irrational or unreasonable findings of fact (referring to cases such as State Super SAS Trustee Corporation v Cornes [2013] NSWCA 257 at [12] and Tolson v Roads and Maritime Services [2014] NSWCA 161; 201 LGERA 367 at [53]).

77. It is not necessary for the Court to express a concluded view on the nature and scope of judicial review under this head because I am not persuaded that the Appeal Panel’s Final Decision is based on any illogical, irrational or unreasonable finding of fact. As noted above, the Appeal Panel found that Mr Asbury suffered from 20% WPI following his right total knee replacement (at [50]); 25% of that impairment was referable to the October 2003 Injuries and 75% was referable to the December 2003 Injuries. The 25/75% split was made on the basis of the Appeal Panel’s clinical assessment of the degree of seriousness of Mr Asbury’s injuries and the terms of the referral (as noted above, a copy of the referral was not included in the Court Book). The Appeal Panel found that the first injury suffered in October 2003 “was relatively minor” (at [43]-[44]), while the injury suffered in December 2003 “was clearly more significant” (at [45]). There is therefore a logical or rational connection between the evidence concerning Mr Asbury’s injuries and those intermediate findings, and between those findings and the 25/75% split adopted by the Appeal Panel.

78. As pointed out by the amici curiae, the plaintiff does not challenge the rationality or logicality of the Appeal Panel’s findings and conclusions at [43]-[45] and [50]-[51]. Rather, its argument is that the Appeal Panel made a reviewable error because it “agree[d] that the [Medical Assessor] was correct in applying all the impairment to the second injury” (at [46]). On one view, it may be difficult to reconcile that statement with the Appeal Panel’s conclusions reached at [43]-[45] and [50]-[51]. It may be that what the Appeal Panel meant by that statement was that it was open to the Medical Assessor to attribute the totality of the impairment to the December 2003 Injuries (but that it was not the only conclusion reasonably open on the evidence). At worst for the Appeal Panel, there is an inconsistency between that statement and its other findings and conclusions. But that alone would not be sufficient to vitiate the Final Decision. As Wigney J observed in KFTJ v Minister for Immigration, Citizenship and Multicultural Affairs [2025] FCA 958 at [80]:

… The concept of legal unreasonableness is concerned with the lawfulness of the exercise of power. Plainly not every lapse in logic on the part of a decision-maker will result in a finding of legal unreasonableness. If, for example, a decision-maker employed irrational or illogical reasoning in making a factual finding which was not an essential or even important plank in the decision, it is unlikely that the decision could be said to be legally unreasonable. Ultimately, the question must be whether the illogical or irrational reasoning in question is such as to vitiate or invalidate the exercise of power, or is such that the exercise of power can be said to have been made without or beyond jurisdiction.

79. Moreover, as Crennan and Bell JJ observed in Minister for Immigration and Citizenship v SZMDS (2010) 240 CLR 611; [2010] HCA 16 at [135], “… a decision will not be illogical or irrational if there is room for a logical or rational person to reach the same decision on the material before the decision maker”. Applying those observations here, if the Appeal Panel’s statement at [46] is put to one side there is a logical and rational basis for the conclusions at [43]-[45] and [50]-[51] which contain the core of the Appeal Panel’s analysis. I accept Mr Kaplan SC’s submission that the statement at [46] is “unconnected to the balance of the panel’s statement of reasons”.

80. Therefore, even if there was a lapse in logic by the Appeal Panel in making the statement at [46], that does not assist the plaintiff, as that statement had no bearing on the Appeal Panel’s critical findings and conclusions at [43]-[45] and [50]-[51].

Ground 5 – failure to provide proper reasons concerning apportionment

81. The plaintiff contends that the Appeal Panel failed to provide adequate reasons for its apportionment of Mr Asbury’s impairment.

82. For the following reasons, I do not consider the Appeal Panel’s reasons on this issue to be inadequate at law. It is evident from the statement of reasons (including the attached Table) that the Appeal Panel considered the December 2003 Injuries to be far more serious than the October 2003 Injuries. It is also evident from those materials that the Appeal Panel considered that at least some proportion of Mr Asbury’s impairment should be attributed to the injuries he sustained in October 2003. Being a specialist decision-making body which included two medical assessors, the Appeal Panel was entitled to rely on clinical judgment when it reviewed and evaluated the medical and other relevant evidence before it in determining the proportion of impairment due to the October and December 2003 Injuries respectively. It applied that judgment in determining how much of Mr Asbury’s WPI should be attributable to those injuries. Contrary to the plaintiff’s submission, I do not consider that the Appeal Panel was obliged to provide any more detailed explanation of why it apportioned the impairment in the way that it did.

Conclusion

83. For all these reasons, the summons filed on 17 June 2025 will be dismissed, with no order as to costs.

84. The Court acknowledges the helpful assistance provided by Mr Kaplan SC and Mr Tsaousidis who nobly agreed to take on the role of amici curiae so as to ensure that there was an active contradictor in the proceeding after all the defendants filed submitting appearances.

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