Mars Australia Pty Limited v Knight

1. [1]

   ADAMSON JA: I agree with Stern JA.

2. [2]

   STERN JA: This appeal under s 353 of the Workplace Injury Management and Workers Compensation Act 1998 (NSW) (1998 Act) arises out of a claim for compensation, including for the cost of bilateral knee replacements, under the Workers Compensation Act 1987 (NSW) (1987 Act) submitted by the respondent, Mr Knight, against the appellant, Mars Australia Pty Limited (Mars), in November 2021. Mr Knight claimed that his employment by Mars as an operations technician, over the period 4 September 2000 to 13 September 2019, was the main contributing cause, or was the main contributing factor to the aggravation and exacerbation, of osteoarthritis in both of his knees such that he had sustained a disease injury within the meaning of either ss 4(b)(i) or (ii) of the 1987 Act. These subsections provide that an injury includes a “disease injury” which means:

3. [3]

   Mars disputed this claim. Mars also contended that even if Mr Knight had suffered a disease injury within s 4(b) of the 1987 Act, it was an employer subsequent to Mars, either Tip Top Bakeries (who employed him from 23 November 2020 until 4 February 2021) or Agrana Fruit (who employed him from 4 to 17 July 2022), and not Mars, that was liable to pay compensation under s 16(1) of the 1987 Act. That subsection relevantly provides:

4. [4]

   By Certificate of Determination dated 1 December 2023, following a hearing on 30 October 2023 and the giving of oral reasons on 27 November 2023 by a member of the Personal Injury Commission (the Member and the Commission, respectively), the Commission determined that:

   1. (1)

      under ss 4(b)(ii) and 16 of the 1987 Act, Mr Knight had sustained injuries to both knees as a result of his employment with Mars, that the deemed date of those injuries was 20 September 2021 and that Mr Knight’s employment with Mars was the main contributing factor to the aggravation of the disease process in Mr Knight’s knees; and

   2. (2)

      Mars was to pay weekly compensation to Mr Knight under ss 36 and 37(1) of the 1987 Act and was also to pay for the costs of and incidental to bilateral knee replacements, including the surgery on 4 April 2023, under s 60 of the 1987 Act.

5. [5]

   Mars appealed against this decision under s 352(1) of the 1998 Act, seeking to have the Certificate of Determination and award of compensation revoked or, alternatively, seeking remittal for redetermination. Under s 352(5), such an appeal is limited to a determination of whether the decision appealed against was or was not affected by any error of fact, law or discretion, and to the correction of any such error. Recently, in State of New South Wales v Culhana [2025] NSWCA 157 (“Culhana”), this Court held that the standard of appellate review to be applied is the correctness standard, applying the approach in Warren v Coombes (1979) 142 CLR 531; [1979] HCA 9 and Fox v Percy (2003) 214 CLR 118; [2003] HCA 22. As explained in Culhana at [91]:

6. [6]

   In so holding, this Court found that the first “general principle” concerning the operation of s 352 of the 1998 Act, as set out by the Workers Compensation Commission constituted by Deputy President Roche in Raulston v Toll Pty Ltd [2011] NSWWCCPD 25; 10 DDCR 156 (“Raulston”) and applied in a series of ensuing decisions (including, in one respect in the present case), was wrong.

7. [7]

   On 2 December 2024, prior to the decision in Culhana, Geoffrey Parker SC, an Acting Deputy President of the Commission (the Acting DP), rejected all of Mars’ grounds of appeal and confirmed the Certificate of Determination save that he amended the deemed date of injury to 18 July 2022 (so as to correctly reflect the Member’s oral reasons).

8. [8]

   Mars now appeals against this decision on two grounds, both of which contend that the Acting DP failed to perform the statutory task required under s 352(5) of the 1998 Act. Mars’ two grounds of appeal correspond to two of the grounds of appeal relied upon by Mars before the Acting DP. The first alleged error, reflected in ground one on this appeal, is that the Member erred in his treatment of the evidence of Dr Matt Lyons, orthopaedic surgeon, to whom Mr Knight had been referred for surgical review in December 2021, and in turn, the Acting DP erred in applying the standard of appellate review as set out in Raulston, which was found, in Culhana, to be wrong. The relevant evidence of Dr Lyons was comprised in letters dated 14 December 2021 and 13 December 2022, both of which were before both the Member and the Acting DP. The second alleged error, reflected in ground two on this appeal, is that the Acting DP erred in not finding that the Member erred in his conclusion as to Mr Knight’s incapacity. This ground of appeal relies in part upon the standard of appellate review applied, but beyond this Mars contends that the Acting DP simply did not deal with the substantive submission advanced by Mars.

9. [9]

   For the reasons set out below, the appeal should be dismissed.

Background

1. [10]

   Mr Knight relied upon three written statements before the Member and was also cross-examined. The Member accepted Mr Knight’s evidence generally, rejecting Mars’ contentions as to his credit. Before the Acting DP, Mars contended that some of the Member’s findings in this regard were erroneous, but the Acting DP rejected those contentions. As discussed in more detail below, there was no express challenge before the Acting DP to the Member’s acceptance of Mr Knight as a generally reliable witness, nor to a number of the Member’s findings consequent upon his acceptance of Mr Knight’s evidence. Those findings which were expressly challenged before the Acting DP are noted below.

2. [11]

   Mr Knight’s evidence, accepted by the Member, was that prior to commencing employment with Mars he had no issues, difficulties or disabilities with his knees. In his role at Mars, Mr Knight was required to fix machinery, namely a palletiser, which involved him getting into the machine on his hands and knees in order to unjam it. This would take between five and ten minutes and Mr Knight estimated that he would have to do this about 30 times per day. The machines were located at the top of a stairway with 14 to 15 stairs and Mr Knight was required to ascend and descend the stairs each time he had to conduct this repair. Mr Knight was also required to perform electrical work on the machines. He said that this work had to be done in awkward positions involving squatting and kneeling. He estimated that this work would take on average about 15 minutes and he would have to do it at least three times per day. The Member noted that Mr Knight was not challenged in respect of the duties that he performed whilst employed by Mars.

3. [12]

   An entry dated 22 October 2008 in a “Register of Injury/Illness Form”, signed by Mr Knight, recorded “Exercising at home, right knee became swollen post jog on 21/10/2008. Today painful and swollen at work”. In oral evidence Mr Knight said he recalled hurting his knee when exercising at home. Mr Knight said in his statement that prior to this he had been experiencing “intermittent aches and pains” but that the symptoms deteriorated whilst jogging. An arthroscopy was performed on 20 April 2009. A medial meniscal tear and arthritic changes in the knee were noted. A file note dated 25 May 2009 reported that the knee was fine, although he continued to have pain in the side of the knee when he went for a run.

4. [13]

   Subsequently, in 2011, Mr Knight had an arthroscopy on his left knee. Again, a meniscal tear and arthritic changes were reported. In oral evidence Mr Knight said that he thought that he felt a popping sensation in his left knee when he was walking the dog. Mr Knight said he had intermittent pain in his knees between 2011 and 2018. By 2018, he said that his left knee pain had worsened to the point that it was a regular pain at the end of each working day. The Member accepted that Mr Knight sustained bilateral knee pain in the course of his employment with Mars well prior to September 2019.

5. [14]

   There were only limited references in the notes of Mr Knight’s general practitioner, Dr Cavanagh, to Mr Knight complaining about his knees. The Member accepted Mr Knight’s evidence that from 2016 (or perhaps even earlier) he had intermittently consulted Dr Cavanagh complaining of bilateral worsening knee pain but that Dr Cavanagh had not recorded this in his notes. The Member found that Mr Knight had “complained of symptoms which I’ve accepted in his knees over the years up until he ceased employment with [Mars]”. Mars unsuccessfully sought to challenge some aspects of this finding before the Acting DP, but did not contend in this Court that the Acting DP erred in rejecting that challenge. Mr Knight’s evidence, which the Member also accepted, was “that those symptoms continued after ceasing” that employment.

6. [15]

   Mr Knight took voluntary redundancy, and 13 September 2019 was his last day of employment with Mars. Mr Knight said that he took the offer for voluntary redundancy as he was having difficulties performing his duties due to his knee injuries. Again, the Member accepted this evidence. A medical exit assessment was conducted on 19 August 2019, at which it was noted that he had bilateral knee pain, “OA” [osteoarthritis], and “Mild/Moderate OA both knees severe [L]. [L] side > [R]”. Left sided low back pain was also noted. As for general health, the assessment noted that he was “fit no major issues”. The Member found that Mr Knight’s declaration in this form should be understood by reference to the fact that he did not at that time realise that “the ongoing persisting pain that he felt over the years in his knees amounted to an injury”. The Member also found that this was the reason why Mr Knight had not, for some time subsequently, provided notice of his claim to compensation to Mars.

7. [16]

   After taking voluntary redundancy, Mr Knight was admitted to Wyong Hospital for a psychological condition. There was no mention of any problem with his knees in the medical records from this hospital admission. On appeal to the Acting DP, Mars contended that the Member had erred in his treatment of this evidence. The Acting DP rejected that ground of appeal and it was not contended before this Court that the Acting DP had erred in so finding.

8. [17]

   On 8 October 2020, Mr Knight completed a pre-employment questionnaire for Forsythes Recruitment. In this questionnaire he indicated that he did not have any prior difficulties engaging in work that might aggravate injuries, such as lifting awkward objects or engaging in repetitive manual work. Mr Knight said that he provided this response because he believed that if he disclosed his injury he would not get employment. The Member accepted this explanation.

9. [18]

   In November 2020, Mr Knight secured employment with Tip Top Bakeries through Forsythes Recruitment. He was employed to work full-time operating a packing machine and he conducted this work from a seated position from which he only needed to rise if the machine became blocked or jammed. If this occurred, he would then stand beside the machine to clear the blockage. This happened about ten times per day. After about ten weeks, a supervisor noticed that Mr Knight was limping and he was shortly thereafter advised that his services were no longer required.

10. [19]

    Mr Knight said that the Tip Top Bakeries work was the lightest employment he could possibly find.

11. [20]

    X-rays on both of Mr Knight’s knees dated 21 September 2021 were reported by Dr Lannan (Dr Lannan’s report) as showing:

12. [21]

    Before the Acting DP, Mars unsuccessfully contended that the Member had disregarded this evidence. It was not contended before this Court that the Acting DP erred in rejecting this contention.

13. [22]

    In November 2021, Mr Knight obtained work with Stephen Smith Contracting Pty Limited. He said that this work primarily involved driving a light commercial van (approximately 70% of the time) but also included some light cleaning work (approximately 30% of the time), noting that an offsider would do the heavier cleaning. Mr Knight described this work as “not physically demanding”. He did this work until July 2022 when his knee condition deteriorated and he was unable to continue.

14. [23]

    On 5 November 2021, Mr Knight completed a “Workers Injury Claim Form” in which he reported pain and discomfort in his left knee from 2018. He said that it was not until 2021, after speaking with an ex-colleague about his problems and then consulting solicitors, that he became aware that he was entitled to make a claim “for simple wear and tear caused by [his] employment” and that he had a “workers compensation injury”. The Member accepted this explanation.

15. [24]

    Mr Knight then worked with Agrana Fruit driving a forklift from 4 to 17 July 2022. He said this was “very light duties”. He was initially told that he would only have to drive the forklift and would not have to get in and out of it, however this did not eventuate and he was required to constantly get in and out of the forklift. He found that he was not able to continue in the role as a result of his knee injuries.

16. [25]

    Mr Knight said that his employment with Mars involved tasks and duties that were much more physically demanding than any of his other employment and his subsequent employment was significantly less physically arduous. Despite the fact that Mr Knight told one of the experts, Dr Dias, that the employment at Tip Top Bakeries was similar to that at Mars, having regard to Mr Knight’s oral evidence and his account to the other two experts, the Member found that the Tip Top Bakeries job was “a much lighter job” than that with Mars.

17. [26]

    Mr Knight underwent bilateral knee replacement surgery in April 2023.

18. [27]

    Before the Member, Mr Knight relied upon expert evidence from an occupational physician, Dr Dias (reports dated 8 August 2022 and 10 July 2023), and the two letters (referred to above) from his treating orthopaedic surgeon, Dr Lyons. Mars relied upon expert evidence from an orthopaedic surgeon, Dr Breit (report dated 19 January 2022). Dr Breit also prepared a second report dated 27 October 2023, which Mars unsuccessfully sought leave to rely upon before the Member. The Member refused Mars’ application to cross-examine Dr Dias. Mars unsuccessfully appealed that decision before the Acting DP but did not, before this Court, seek to challenge the Acting DP’s rejection of that ground of appeal.

19. [28]

    Dr Dias was asked to respond to a number of questions and he was provided with a range of documents from Mr Knight’s records, including Dr Lannan’s report referred to at [20] above. Dr Dias’ first report canvassed Mr Knight’s medical and employment history in some depth. He recorded that:

20. [29]

    Dr Dias noted that Mr Knight did not have any previous injuries or known pre-existing conditions affecting his knees prior to commencing employment with Mars, but that within three to four years of commencing this employment he began to experience symptoms of intermittent pain, stiffness and discomfort affecting both knees. These symptoms were generally intermittent and would resolve with anti-inflammatory tablets but would then be exacerbated by the nature and conditions of his employment at that time.

21. [30]

    He also noted that Mr Knight sustained a “right knee meniscal tear” when walking his dog (as set out above, Mr Knight’s evidence was that he thought that this was an incident involving his left knee) and that he underwent a procedure to address this on 20 April 2009. Dr Dias observed that Mr Knight was noted to have “Grade III osteoarthritic change throughout most of the medial compartment of his right knee” at this time. Dr Dias also noted that Mr Knight had experienced worsening symptoms in his left knee in early 2011 and underwent a procedure on 27 June 2011 to address this. At this time “Grade III-IV degenerative changes affecting the medial compartment” were observed. Over the next few years his symptoms of bilateral knee pain worsened until they were unremittingly severe. By September 2019 he could not cope with the demands of his job due to this pain.

22. [31]

    Dr Dias said that Mr Knight described his job with Tip Top Bakeries as “similar to his long-standing pre-injury job role with Mars” (as set out above, the Member made a factual finding somewhat different to this) which led to a “transient exacerbation of bilateral knee pain, which reverted back to his baseline level of symptomatology” after he ceased that employment after 10 weeks. Dr Dias referred also to Mr Knight’s employment with Steven Smith Contracting, stating that Mr Knight could not cope with even this “light and sympathetic employment”.

23. [32]

    Dr Dias noted that Mr Knight continued to suffer from “chronic symptoms of bilateral knee pain, stiffness and discomfort on a daily basis.”

24. [33]

    With respect to Mr Knight’s “compensable physical injuries stemming from the nature and conditions of his employment” with Mars, Dr Dias said that his symptoms and signs were consistent with:

25. [34]

    In response to a question as to the cause of Mr Knight’s condition, Dr Dias stated that:

26. [35]

    Dr Dias said the injuries had caused an “aggravation, acceleration and exacerbation of a pre-existing asymptomatic condition, namely degenerative tricompartmental bilateral knee osteoarthritis” and that Mr Knight’s employment with Mars was “a substantial contributing factor” and the “main contributing factor” to these injuries.

27. [36]

    In respect of Tip Top Bakeries, Dr Dias stated that Mr Knight’s “symptoms of bilateral knee pain were transiently exacerbated, by the nature and conditions of his employment with Tip Top Bakeries however soon reverted to their baseline chronic level within one to two months of ceasing employment with Tip Top Bakeries” and that this employment was “not causally attributable to the causation or aggravation [of] his conditions affecting his right and left knees”. As to Mr Knight’s employment with Steven Smith Contracting, Dr Dias said that this did not result in “any aggravation or exacerbation of his work-related injuries affecting his right and left knees, which in my opinion, are causally attributable to his 19-year employment tenure with Mars”.

28. [37]

    Dr Dias’ supplementary report confirmed his opinion that Mr Knight’s employment with Mars was the main and substantial contributing factor to the injuries affecting his knees. When asked about the role of Mr Knight’s employment subsequent to his employment with Mars, Dr Dias said:

29. [38]

    When asked whether any other employment was the main and substantial contributing factor to Mr Knight’s injuries, he responded:

30. [39]

    The first letter from Dr Lyons, dated 14 December 2021, is a letter to Dr Cavanagh noting that Dr Lyons had seen Mr Knight that day and that he presented with bilateral knee pain that:

31. [40]

    Based on a review of Mr Knight’s x-rays, Dr Lyons identified “advanced arthritic changes of the medial compartment” and “chondrocalcinosis of the lateral compartment and lesser arthritic changes of the patellofemoral compartment”. Dr Lyons said that a diagnosis of osteoarthritis was discussed with Mr Knight and that arrangements would be made for a total knee replacement.

32. [41]

    Subsequently, on 13 December 2022, Dr Lyons responded in writing to a number of questions posed in a letter of instruction dated 13 September 2022 from Mr Knight’s solicitors. The letter of instruction included a statement that:

33. [42]

    Dr Lyons was provided with Dr Dias’ report dated 8 August 2022 for this purpose. As set out at [30] above, that report included reference to the circumstances preceding Mr Knight’s arthroscopies.

34. [43]

    Dr Lyons confirmed that Mr Knight was suffering from “tricompartmental osteoarthritis of his knees”. In response to a question “What is the cause of our client’s condition?”, Dr Lyons said:

35. [44]

    In response to a question whether Mr Knight had “any pre-existing condition”, Dr Lyons said:

36. [45]

    In response to being asked “Do you believe that work was a substantial contributing factor to our client’s injury?”, Dr Lyons said:

37. [46]

    When asked “If you believe that our client’s injury is a disease and/or was an aggravation, acceleration, and/or exacerbation of a pre-existing condition or disease, do you believe that their employment was the main contributing factor to the injury”, Dr Lyons said:

38. [47]

    Dr Lyons’ report otherwise indicated that Mr Knight was totally incapacitated for work, however he had a significant chance of returning to his pre-injury capacity and achieving work related duties following a bilateral total knee replacement.

39. [48]

    Under the heading “Employment History”, Dr Breit noted:

40. [49]

    This was the only information in Dr Breit’s report about Mr Knight’s duties in his employment with Mars.

41. [50]

    Dr Breit diagnosed Mr Knight with bilateral knee arthritis.

42. [51]

    In response to a question as to whether Mr Knight’s employment with Mars was the main contributing factor to his injury, Dr Breit said:

43. [52]

    Dr Breit also said that he did not consider that Mr Knight’s employment by either Tip Top Bakeries or Steven Smith Contracting had been “relevant or contributing”. This was because the condition or pathology in Mr Knight’s knees was a disease process unrelated to those jobs, and “[Mr Knight had] described his short-term work at Tip Top as being ‘cruisy’ and his subsequent work has not been onerous either”.

44. [53]

    As to capacity, Dr Breit’s opinion was that although Mr Knight suffered from incapacity, this was not work-related.

The Member’s decision

1. [54]

   As the Acting DP observed, the transcribed oral reasons of the Member are “difficult to follow and understand” and “the findings supporting the Member’s determination are not always easily identified”. The Member’s key conclusions are, however, tolerably clear.

2. [55]

   First, as already noted, the Member found Mr Knight to be generally credible and accepted much of his evidence.

3. [56]

   Second, the Member preferred the report and opinion of Dr Dias to that of Dr Breit and accepted the opinion of Dr Dias. The Member did not accept Dr Breit’s opinion as to causation because he found that Dr Breit did not engage with Mr Knight’s specific employment duties at Mars and instead had “argued that it was simply a blanket argument that the employment duties are not related to [Mr Knight’s] condition” without explaining why specified employment duties were not so related. By contrast, the Member observed, Dr Dias took a detailed history of Mr Knight’s duties, the prior arthroscopies and the onset of symptoms (which the Member had accepted).

4. [57]

   Third, as to Dr Lyons, the Member noted Mars’ submission that Dr Lyons had the history wrong to the extent that he had made “an assumption that the meniscal tears occurred in the context of [Mr Knight’s] work duties with [Mars] given [Mr Knight’s] unequivocal evidence that each knee was injured in circumstances occurring outside the workplace”. The Member noted Dr Lyons’ unequivocal view that Mr Knight’s work duties at Mars were a substantial contributing factor to the arthritic process. The Member also noted that there was no discussion in Dr Lyons’ report of “the circumstances in which [Mr Knight] thereafter underwent surgery to each knee”, and that while he had said that his work precipitated the meniscal tears, this was “not fatal” to his opinion. The Member said that what was important was Dr Lyons’ “more detailed than Dr Breit’s” recording of the duties Mr Knight undertook at Mars and his opinion as to the deterioration in Mr Knight’s condition during his employment with Mars. That provided “a fair climate” for Dr Lyons’ opinion which the Member interpreted on the basis that it lent support to Mr Knight having suffered an aggravation of a pre-existing degenerative condition in circumstances where “an assumption … can’t be made out one way or the other as to whether or not those earlier arthroscopies were related to [Mr Knight’s] employment”. Thus, the Member found that Dr Lyons’ opinion “still stands”.

5. [58]

   Fourth, the Member upheld Mr Knight’s claim that the bilateral osteoarthritis in his knees was an aggravation of a pre-existing degenerative condition of osteoarthritis in both knees which was due to the nature of Mr Knight’s employment with Mars. The Member said that his conclusion was supported by a “common sense appraisal of the causal chain”, which was supported by Dr Cavanagh’s notes, Mr Knight’s evidence both in his statements and in cross-examination and the opinions of both Dr Lyons and Dr Dias. Significantly, explaining his key conclusion that Mr Knight’s employment with Mars caused the injury to his knees, the Member said:

6. [59]

   As is apparent, the Member here relied upon Dr Dias’, but not Dr Lyons’, opinion as to causation (which he also accepted). He relied upon Dr Lyons’ opinion as to the injury to Mr Knight’s knees being a disease process.

7. [60]

   Fifth, the Member noted that none of the experts said that Mr Knight’s employment subsequent to Mars was related to his bilateral knee conditions and rejected Mars’ submission to this effect. In this regard, the Member also relied upon Mr Knight’s evidence as to the continuity of his symptoms in both knees after 2019, and upon his rejection of Mars’ contentions that Mr Knight’s symptoms had not deteriorated in the course of his employment at Mars.

8. [61]

   Sixth, the Member found that the date from which Mr Knight ceased to have any capacity for work was 18 July 2022, being the day after his last day working for Agrana Fruit (albeit that, as noted by the Acting DP, the Certificate of Determination did not accurately reflect this date of incapacity).

The decision of the Acting DP

1. [62]

   The grounds of appeal to the Acting DP were:

2. [63]

   Ground 2(b) reflects ground one in this Court. Ground 2(c) reflects ground two in this Court. Given the ambit of ground two in this Court, and that it indirectly raises issues under other grounds, it is necessary to refer to the Acting DP’s reasons for rejecting all grounds of appeal.

3. [64]

   The Acting DP summarised the most important facts and findings of the Member. These included that the Member had generally accepted the credibility of Mr Knight; that the Member had observed that Mr Knight had not been challenged as to the duties he performed at Mars; that the Member had accepted Mr Knight’s evidence that the work at Tip Top Bakeries was lighter than the work with Mars and Dr Dias’ finding that the Tip Top Bakeries job had caused a “transient exacerbation” of the bilateral knee pain; that the Member preferred the evidence of Dr Dias to that of Dr Breit and did not accept Dr Breit’s opinion as to causation; and that the Member did not accept that Mr Knight’s condition deteriorated after leaving the employ of Mars.

4. [65]

   As regards Mars’ contentions on ground 1, the Acting DP described Mars’ complaint as being, in part, that “the Member failed to provide adequate reasons for not accepting [Mars’] submission of a tangible worsening of [Mr Knight’s] knee problems in conjunction with subsequent employment”; that the Member had relied in this regard simply on the opinions of Dr Dias and Dr Lyons; and that the Member’s reasons were logically inconsistent with the fact that the date of injury was two to three years after Mr Knight ceased employment with Mars. As is apparent, these contentions attack both the logic of the Member’s reasoning and the adequacy of the reasons given. The Acting DP’s reasons for rejecting these contentions relied upon the Member’s acceptance of Mr Knight’s evidence in key relevant respects, including that Mr Knight had been hanging on for a voluntary redundancy notwithstanding chronic debilitating pain, and upon the Member’s acceptance of the evidence of Dr Dias.

5. [66]

   As regards Dr Lannan’s report, the Acting DP rejected the contention that the Member had erred in his treatment of this report, noting that Mars’ proposition that Dr Lannan’s report showed changes that were consequent upon Mr Knight’s work at Tip Top Bakeries “does not follow from the report”. The Acting DP observed that the medical evidence accepted by the Member did not demonstrate that the radiological changes were due to work at Tip Top Bakeries or the subsequent employment.

6. [67]

   As regards the Member’s treatment of Dr Lyons’ report, Mars submitted that Dr Lyons’ report was flawed because he assumed that the bilateral meniscal tears were caused by employment, whereas the evidence demonstrated that these injuries were caused by events occurring outside of the workplace. As to this, the Acting DP found that:

7. [68]

   A footnote to [178] of the Acting DP’s decision referred to the decision of Raulston which, as I have already observed, was disapproved of in Culhana.

8. [69]

   As to the contention that the Member erred in his conclusions as to Mr Knight’s incapacity, Mars’ written submissions before the Acting DP stated that its submissions at first instance pointed overwhelmingly to the conclusion that:

   1. (1)

      Mr Knight was not incapacitated at the time his employment with Mars ceased;

   2. (2)

      Mr Knight’s employment at Tip Top Bakeries and Agrana Fruit was aggravating and caused a deterioration in his condition;

   3. (3)

      Employment subsequent to Mr Knight’s employment with Mars was the main contributing factor to the aggravation of the pre-existing osteoarthritic changes; and

   4. (4)

      The date of incapacity as found by the Member, which occurred after cessation of employment with Mars, was not reflective of aggravation caused by employment with Mars and established that Mars was not the last relevant employer for the purposes of the 1987 Act.

9. [70]

   There was a footnote to this submission that referred to Mars’ submissions before the Member at “[9][a]-[pp]”. Paragraph 9 of those submissions had the chapeau “[t]he evidence up to [late 2021] bears careful analysis, and in particular”, followed by 42 sub-paragraphs referring to aspects of the evidence. Those 42 sub-paragraphs can be broadly summarised as referring to:

   1. (1)

      The arthroscopies in 2009 and 2011 and to the circumstances preceding those operations and the lack of symptoms prior to 2008 (a, b, c, d, f, g);

   2. (2)

      Accommodations (including the availability of an occupational health nurse) made for Mr Knight at Mars after those procedures, the willingness of Mars to make those accommodations, and the lack of any certificates restricting Mr Knight’s capacity to work or request for modification of work whilst at Mars and an alleged inconsistency in Mr Knight’s evidence that he thought Mars would only accommodate a week of suitable duties (d, e, h, i, j, k, p, q, r);

   3. (3)

      The records of Dr Cavanagh, referred to at [14] above (l, m, y);

   4. (4)

      Mr Knight’s awareness of the option of voluntary redundancy and the timing of him taking redundancy (n, o);

   5. (5)

      The terms of Mr Knight’s exit medical assessment (s, t);

   6. (6)

      The Wyong Hospital notes, referred to at [16] above (u, v, w);

   7. (7)

      The Forsythes Recruitment questionnaire and the information on a Forsythes document, referred to at [17] above, and that he made himself available for medical assessment at that time (x, z, aa);

   8. (8)

      Dr Dias having recorded that Mr Knight said that his work at Tip Top Bakeries was similar to that at Mars, and that that work was described in documents produced by Forsythes Recruitment as not entirely sedentary and the fact that Mr Knight was limping at Tip Top Bakeries, and that Mars had not been permitted to cross-examine Dr Dias (cc, dd, ee, ff, gg, hh, ii);

   9. (9)

      Dr Lannan’s report (jj, kk); and

   10. (10)

       That Mr Knight was recorded as being in pain in 2021 but denied worsening symptoms, that his employment at Agrana Fruit was also provocative, and generalised assertions as to conclusions that should be drawn from the contemporaneous records or evidence as a whole (bb, mm, nn, oo, pp).

10. [71]

    The Acting DP rejected these contentions, explaining:

11. [72]

    The Acting DP also rejected Mars’ contentions that the Member had erred in his treatment of the evidence relating to Mr Knight’s admission to the Wyong Hospital and in his treatment of the evidence “as to the absence of complaint to Dr Cavanagh”. As to the latter, the Acting DP placed weight on the Member’s acceptance of the evidence of Mr Knight.

The grounds of appeal to this Court

1. [73]

   Mars relies upon two grounds of appeal:

Relevant principles

1. [74]

   As already noted, this is an appeal under s 353(1) of the 1998 Act, which provides:

2. [75]

   The nature of such appeal was considered in Fisher v Nonconformist Pty Ltd (2024) 114 NSWLR 1; [2024] NSWCA 32 (“Fisher v Nonconformist”) at [50] by Kirk JA (Meagher JA and Simpson AJA agreeing):

3. [76]

   To similar effect, in Culhana, Leeming JA explained:

4. [77]

   In circumstances in which there is nothing in the judgment of Leeming JA to suggest that his Honour was intending to reflect a test for materiality different from that identified by Kirk JA in Fisher v Nonconformist (which reflected, in turn, well established authority as to the threshold for materiality in other contexts), I would read the words “would make a difference” in the last sentence of [92] of Culhana as nothing more than shorthand for the materiality threshold as set out in Fisher v Nonconformist at [50]. Contrary to Mars’ submission before this Court, I would also not read Culhana at [93] as suggesting that a different approach should be taken to the issue of materiality depending upon whether or not the error of law was in applying the wrong standard of appellate review. The issue of materiality should, in all cases, be approached in the manner explained by Kirk JA in Fisher v Nonconformist. Where, however, the appellate court finds that there is only one legally correct conclusion on a particular legal or factual issue, that finding may be of determinative significance on the issue of materiality if the substantive outcome in the case depends upon that particular issue.

Consideration

1. [78]

   Mars’ contention under ground one, simply stated, is that the Acting DP applied the wrong standard of appellate review when considering Mars’ contention that the Member had erred in the conclusions that he had expressed as regards Dr Lyons’ evidence. Mars contended that the Acting DP should have applied the correctness standard of appellate review but, instead, the Acting DP rejected Mars’ contention on the basis that the Member’s interpretation of Dr Lyons’ opinion was “open to him”. Mr Knight, for his part, contends that the Acting DP did not err. He submits that it is important to look beyond the language used by the Acting DP, and to focus upon the substance of his reasoning which was to affirm the correctness of the Member’s interpretation of Dr Lyons’ report.

2. [79]

   I agree with Mr Knight’s contention that it is important to focus upon the substance of the Acting DP’s reasoning having regard to his decision as a whole. Taking that approach does not, however, resolve the difficulty identified by Mars. The inescapable fact is that the Acting DP, having identified the ambiguity in Dr Lyons’ report as regards the causation of the meniscal tears, goes no further than to identify that the Member’s “reading of the reports” was open to him. On that basis, having regard to the now disapproved of authority of Raulston, the Acting DP found that Mars’ contention as to error should be rejected. In so reasoning, the Acting DP erred in point of law.

3. [80]

   It is thus necessary to consider whether or not this error is material in the sense that it could realistically have made a difference to the result before the Acting DP. Mars’ contention in this regard is that Dr Lyons’ report could be read as providing support for the opinion of Dr Breit, which could, in turn, have led to Mr Knight’s claim for compensation being dismissed. Mars also submits that it is entitled to a determination by a Deputy President, being an expert body, of its submissions as to the proper interpretation and significance of Dr Lyons’ report.

4. [81]

   Those contentions should be rejected. The Member rejected Dr Breit’s evidence and accepted the evidence of Dr Dias. That analysis did not depend upon the terms of Dr Lyons’ report, albeit that the Member did regard Dr Lyons’ report as supportive of his conclusion as to causation. Moreover, Dr Lyons’ report, whilst somewhat ambiguous as to whether or not Dr Lyons was intending to suggest that the meniscal tears in Mr Knight’s knees were the result of the work he undertook in his employment at Mars, cannot be read so as to provide support for Dr Breit’s opinion. On no view does Dr Lyons suggest that Mr Knight’s bilateral osteoarthritis was unrelated to work duties, or that arthroscopic procedures inevitably result in osteoarthritis (which was the gravamen of Dr Breit’s opinion).

5. [82]

   Thus, whilst there is ambiguity as to whether or not Dr Lyons considered that Mr Knight’s employment duties at Mars themselves contributed to his meniscal tears, and whether or not in reaching that conclusion he took into account the history preceding the arthroscopies in 2009 and 2011 as recorded in Dr Dias’ report (which Dr Lyons was provided with), that ambiguity could, at most, have led to Dr Lyons’ opinion being discounted (as to some extent it was by the Member: see [57] above). That would still have left the report of Dr Dias, which was accepted by the Member, and which supported Mr Knight’s claim. Further, the Acting DP held at [182] of his reasons that there was no error in the Member’s conclusions as to incapacity “based as they are on acceptance of [Mr Knight’s] and Dr Dias’ evidence”. That reinforces the conclusion that this was the critical evidence upon which the outcome of the appeal turned. However it was interpreted, Dr Lyons’ report could not have undermined the force of that evidence.

6. [83]

   In follows that there is no realistic possibility that the Acting DP would have upheld Mars’ appeal from the Members’ decision if he had applied the correct standard of appellate review.

7. [84]

   Mars’ contention in ground two is that the Acting DP erred in failing to appreciate, or substantively to consider, that Mars’ contention in ground 2(c) relied upon all of the matters identified in paragraph 9 of Mars’ submissions before the Member, which are summarised above at [70]. These, Mars contends, challenged a multitude of the Member’s findings, including his overarching conclusion as to the credibility of Mr Knight’s evidence. Mars submits that, in this way, Mars made a substantive, clearly articulated, contention, which the Acting DP did not engage with, that the Acting DP should revisit all of the credit and factual findings that led to the Member’s ultimate conclusion. Further, Mars contends, the Acting DP erred in stating that Mars’ submissions under ground 2(c) were largely repetitive of what was advanced in respect of its other grounds and had been dealt with in that context. In this regard, Mars contends that there was a constructive failure to exercise jurisdiction: Dranichnikov v Minister for Immigration and Multicultural Affairs [2003] HCA 26; 77 ALJR 1088. Mars also contends that the Acting DP applied the wrong standard of appellate review, relying upon Culhana.

8. [85]

   Mars’ contentions should be rejected for three reasons.

9. [86]

   First, a constructive failure to exercise jurisdiction depends upon there having been a substantial, clearly articulated, argument relying upon established facts which the relevant decision-maker failed to consider or engage with. Mars’ submissions before the Acting DP challenged the Member’s conclusion that Mr Knight suffered incapacity as a result of his employment with Mars. That substantial, clearly articulated, argument was directly engaged with by the Acting DP and rejected. There was no constructive failure to exercise jurisdiction.

10. [87]

    Had Mars sought, for example, to challenge the Member’s credit findings before the Acting DP, it could, and should, have included a ground of appeal to that effect, much as it included a number of grounds of appeal challenging specific aspects of the Member’s decision-making. Such a submission would, of course, have had to grapple with the limitations on appellate review of fact finding, which are well recognised and are reiterated in Culhana. Mars’ submissions made no attempt to engage with those limitations. Mars’ submissions before the Acting DP fell well short of directly raising a challenge to the Member’s acceptance of the credibility of Mr Knight’s evidence. The same analysis applies as regards the other matters of fact raised in Mars’ submissions before the Member at paragraph 9.

11. [88]

    Second, and in any event, as is clear from the summary of the Acting DP’s decision set out above, the Acting DP engaged with many of the matters raised in paragraph 9 of Mars’ submissions before the Member. The Acting DP’s analysis of Mars’ reasons challenge (ground one before the Acting DP), engaged with contentions as to illogicality of the Member’s reasoning having regard to the evidence. The Acting DP also engaged with Mars’ criticisms of the Member’s findings as regards Dr Lannan’s report, Dr Cavanagh’s notes and what was or was not said at Mr Knight’s Wyong Hospital admission. In addition, as is clear from my summary of Mars’ contentions in paragraph 9 of its submissions before the Member at [70] above, in large measure the matters raised went to the credit of Mr Knight. As the Acting DP observed, given this, Mars’ contentions went nowhere given the Member’s acceptance of the evidence of both Mr Knight and Dr Dias.

12. [89]

    Third, it is clear that the Acting DP considered the correctness of the Member’s conclusion as to incapacity, and did not apply the wrong standard of appellate review. There is nothing in the Acting DP’s analysis that suggests he limited his consideration only to what conclusion was “open” to the Member.

13. [90]

    In these circumstances, ground two should be rejected.

Conclusion

1. [91]

   It follows from my reasons as set out above that the appeal should be dismissed. Mars sought the opportunity to make written submissions as to costs after we delivered reasons. That opportunity should be given.

2. [92]

   I propose the following orders:

   1. (1)

      Appeal dismissed.

   2. (2)

      Mars Australia Pty Limited is to file and serve submissions as to costs, of no more than three pages, by 4 pm on 27 October 2025.

   3. (3)

      Mr Knight is to file and serve responsive submissions as to costs, of no more than three pages, by 4 pm on 3 November 2025.

   4. (4)

      The issue of costs will be determined on the papers.

3. [93]

   BALL JA: I agree with Stern JA.