Smith v Comcare

A brief history of the litigation 11 (a) Comcare's primary decision: As noted above, Mr Smith lodged an application for workers compensation under the SRC Act in 2009. On 10 December 2009, Comcare determined that there was no liability under s 14 of the SRC Act, which decision was affirmed on an internal review on 6 May 2010. 12 (b) The AAT's first decision: Mr Smith appealed Comcare's determination to the AAT. His appeal was unsuccessful (the AAT's first decision). Reasons were given for the AAT's first decision on 28 September 2011. The following paragraphs in those reasons are relevant (emphasis added): 13. For sheep, three stations were involved: fronts, viscera and final inspection. Mutton inspection was the most difficult because the process was faster than for beef and required more repetitive bending and twisting. This was particularly so for the fronts because these were hung very low. … 18. [At Wagga] there was no inspection of pigs and Mr Smith spent about half of his time each on beef and mutton until 1993 and then dealt only with cattle. He was assigned regular overtime hours until 1993. He continued to undertake hygiene inspections and load out duties about once per week until about 2000 when meat inspectors were relieved of those functions. From 1993, Mr Smith worked overtime on about 10 to 12 Saturdays per year. … 78. A summary of the conclusions in the [research] reports referred to in [the various expert medical report in] this matter read: • "Occupational activity and the risk of hip osteoarthritis" by Cooper et al noted an increased risk to farmers but considered that it was "currently unclear whether the excess risk might be found in other heavy manual workers, for example construction workers and labourers". It referred to a British study which found hip osteoarthritis was "related to occupations which entailed regular heavy lifting (for example, the daily moving of weights greater that 25 kg by hand), prolonged standing, and walking over rough ground". • "Osteoarthritis of the hip in women and its relation to physical load at work and in the home" by Vingard et al concluded that high physical loads at work and in the home undertaken up to the age of 50 seem to be risk factors for development of severe osteoarthritis of the hip in women. • "Osteoarthritis of the Hip and Occupational Lifting" by Coggan et al concluded that there was a strong case for regarding hip osteoarthritis as an occupational disease in men whose work involved prolonged and frequent heavy lifting. It noted that risk was elevated in those who regularly lifted weights of 10 kg or more. • "Influence of Work on the Development of the Hip: A Systematic Review" by Lievense et al concluded that there was moderate evidence of a positive relationship with hip osteoarthritis and lifting heavy weights of 25 kg or more. • "Hip osteoarthritis; influence of work with heavy lifting, climbing stairs or ladders, or combining kneeling/squatting with heavy lifting" by Jensen concluded that there was moderate evidence of a relationship between osteoarthritis hip and lifting where the burden was at least 10 to 20 kgs for at least 10 to 20 years. • "Risk factors for the development of hip osteoarthritis: a population-based prospective study" by Juhakoski et al concluded that heavy physical stress at work and major musculoskeletal injuries are associated with an increased risk of developing clinically diagnosed hip osteoarthritis. It also found that heavy manual labour proved to be a significant predictor of the development of hip osteoarthritis. There, heavy manual work was defined as "either mostly standing work involving much lifting of light objects or lifting and carrying heavy objects … " • "Associations of Occupational Tasks with Knee and Hip Osteoarthritis: The Johnston County Osteoarthritis Project": by Allen et al concluded that, for hip osteoarthritis, a particularly strong and consistent association was observed for lifting tasks, with the strongest and most consistent evidence being for an overall heavy physical workload and heavy lifting. 79. The majority of those studies and, indeed, the medical reports in evidence support the need for heavy lifting in employment in order to have an association with hip osteoarthritis. The Juhakoski report also implicated light objects but only in the context of "much lifting" thereof. Dr Browne, who implicated the employee's flexed position to be relevant, also required that to be done in the context of lifting. His evidence in relation to the DVD was that he observed no lifting. I am satisfied that Mr Smith's meat inspection duties at Wagga did not involve him in heavy lifting and that the only lifting of any moment was in relation to the turning of items at the viscera table. Even in that regard, the motion was more one of quickly flipping the item over rather than of lifting. I am satisfied that Mr Smith's inspection duties at Wagga did not make a material contribution to the aggravation of his hip osteoarthritis. … 81. On Mr Smith's evidence, the work at Wagga was more onerous prior to 1993 when he was involved in mutton as well as beef inspections. However, the evidence of Dr Browne and Professor Sambrook was that the aggravation of Mr Smith's hip osteoarthritis in 1997 was related to his activity in the years immediately preceding that onset. 13 The AAT concluded in its first decision that it was not satisfied that Mr Smith's employment as a meat inspector had materially contributed to his hip osteoarthritis. Accordingly, Comcare's primary decision was affirmed. 14 (c) Review of the AAT's first decision by the Federal Court: Mr Smith sought a review of the AAT's first decision in the Federal Court under s 44 of the Administrative Appeals Tribunal Act 1975 (Cth) (the AAT Act). He claimed that the AAT had asked itself the wrong question by first determining for the purposes of s 7(4) of the SRC Act that Mr Smith's injury had been sustained in 1997, which caused it then erroneously to focus only on Mr Smith's employment in 1997 in determining whether such employment had contributed to the aggravation of his hip condition for the purposes of determining whether Comcare was liable under s 14 of the SRC Act. The relevant question, Mr Smith claimed at the time, was whether his employment over the whole period from 1977 to November 2008 (when he stopped work due to severe pain in his right hip) had contributed to his osteoarthritis. The focus of Mr Smith's appeal was on [81] of the AAT's reasons for the first decision, which is set out in [12] above. 15 The primary judge held that, contrary to Mr Smith's contention, this paragraph did not indicate that the AAT had limited its consideration of the question arising under s 14 as to whether Mr Smith's employment had contributed to the aggravation of his hip condition by focusing only on his employment in 1997 and not over its entire period. His Honour emphasised the reference at the beginning of [81] of the AAT's reasons to Mr Smith's work at Wagga prior to 1993, which indicated that it had not confined its attention to his employment in 1997 alone. The primary judge added that it was unnecessary for the purposes of making a determination under s 14 to first identify the timing of the onset of the injury for the purposes of s 7(4), but that any error in this respect had no impact on the manner in which the AAT approached the issue of material aggravation because the AAT did look at his employment during the entire period from 1977 to 2008. 16 (d) Mr Smith's first appeal to the Full Court: Mr Smith's appeal from the primary judge's decision was successful. The reasoning of the majority of the Full Court (Buchanan J, with whom Greenwood J agreed; Bromberg J dissenting) is reflected in the following extracts from Buchanan J's reasons for judgment: [4] In this matter an error of law was, in my respectful opinion, made by the AAT. That does not mean necessarily that the AAT reached the wrong result on the facts or the merits of the case, but in my view that possibility cannot be excluded with sufficient confidence to reach a conclusion that the matter should not be remitted to the AAT for further attention. … [5] The error of law made by the AAT was that it stated conclusions, unnecessarily and ultimately contrary to its own findings on liability, about the issue of when a 'disease' within the meaning of s 4 of the Safety Rehabilitation and Compensation Act 1988 (Cth) (as it stood at the time relevant to this litigation: see Safety, Rehabilitation and Compensation and Other Legislation Amendment Act 2007 (Cth), sch 1, s 5) ("SRC Act") should be taken to have been sustained within the meaning of s 7(4) of the SRC Act, for the purpose of the present case. … [24] In its discussion about the significance of the medical evidence for the claim that the appellant's work had materially contributed to the aggravation of his osteoarthritis, the AAT concluded that it would need to be shown that the appellant had been involved in "heavy lifting". The AAT then assessed whether the appellant's duties 'at Wagga' involved him in heavy lifting and (at [79]) found they did not: 79. … I am satisfied that Mr Smith's meat inspection duties at Wagga did not involve him in heavy lifting and that the only lifting of any moment was in relation to the turning of items at the viscera table. Even in that regard, the motion was more one of quickly flipping the item over rather than of lifting. I am satisfied that Mr Smith's inspection duties at Wagga did not make a material contribution to the aggravation of his hip osteoarthritis. [25] Other references made by the AAT (at [80] and [82]) to the appellant's duties also concerned the period he was at Wagga. The appellant had been employed at the Forbes abattoir in the New South Wales public service from 1981, and by the Commonwealth at Forbes from 1983, before he went to Wagga in 1987. The AAT's conclusions make no reference to this earlier period of employment by the Commonwealth which was a part of the appellant's case. … [35] … The error was making a finding about a matter which arose under s 7(4) of the Act without any foundation upon which to do so, whether by way of prior finding for the purpose of s 14 or by way of assumption. … [38] In my respectful view, it is not sufficiently clear that the AAT did, in fact, assess the whole period from 1977 to 2008 (more precisely, 1983 to 2008). Perhaps it was deflected from doing so by a view of the medical evidence that the aggravation of the appellant's hip osteoarthritis was likely to be found in events no more than a few years prior to 1997, rather than potentially in the whole period from at least 1983. If so, that is hard to reconcile with reference to the various studies suggesting a relationship between a history of heavy lifting over many years, followed by a later onset of osteoarthritis. That evidence suggests that consideration would need to be given to the whole of the relevant period of employment, and that it may not be the case that symptoms would emerge within a few years of the relevant activity beginning. [39] I cannot exclude from my own mind the reasonable possibility, for which the appellant contended, that the AAT's premature and unnecessary attention to the question in s 7(4) might have sent it on the wrong line of enquiry about the issues arising under s 14. The conclusions by the AAT stated in [81] of its decision (set out earlier) give sufficient (even if not decisive) support for that thesis. 17 The Full Court made the following orders: 1. The appeal is allowed with costs. 2. The matter is remitted to the Administrative Appeals Tribunal for further consideration and determination according to law. 18 It is to be noted that the Full Court did not make an order that the AAT's first decision be set aside, even though the appellant had sought such an order in his notice of appeal. 19 (e) The AAT's second decision: In accordance with the Full Court's orders, the matter was remitted to the AAT for consideration according to law. The remitted proceedings were conducted by the same member of the AAT who had heard and determined the first appeal. In an interlocutory decision, the AAT ruled that the remitted matter should proceed as a hearing on the papers and without any further evidence being admitted. These rulings were not challenged by Mr Smith. 20 In his written submissions to the AAT on the remittal, Mr Smith submitted that the relevant period of employment for his claim was from 1983 until 1993, and not the whole of his Commonwealth employment from 1983 to 2008 as he had previously contended. He explained that this was primarily because he contended that his duties in those years, as they related to the inspection of mutton at Forbes and, until 1993, at Wagga, were the most significant factor in the aggravation of his hip condition. 21 The AAT delivered reasons for its second decision on 22 January 2014 in which it again affirmed Comcare's decision under review (the AAT's second decision). In [3] of these reasons, the AAT described the relevant error in the AAT's first decision as found by the majority of the Full Court: The majority of the Federal Court determined that it was not sufficiently clear in the AAT decision that the whole of the period of the applicant's Commonwealth employment from 1983 was taken into account in assessing material contribution to his ailment. Rather, it determined, the AAT may have been distracted by its finding that the ailment had its onset in 1997 and may only have considered such contribution during the few years prior to 1997. 22 In [6] of its reasons for the second decision, the AAT made reference to the fact that in [13] and [18] of its reasons concerning the first decision (which are set out in [12] above), it had described aspects of Mr Smith's work at Forbes and at Wagga in relation to his inspection of mutton carcasses and other duties. 23 After describing Mr Smith's evidence regarding his inspection of beef and mutton at Forbes, the AAT noted that Mr Smith described his mutton inspection duties at Wagga as worse than at Forbes in terms of speed, repetition and the amount of twisting and bending involved, because the product was presented at a lower level and the sheep were older at Wagga, which required more pathology to be removed. The AAT then made the following observations at [8]: Clearly, on those descriptions, the applicant regarded the work associated with inspection of mutton at Forbes and Wagga as more onerous for him than were his beef-related duties. In the initial decision, I noted the applicant's evidence that his duties were more onerous prior to 1993 when he was involved with inspection of mutton as well as beef. However, my finding in the initial decision was that the evidence before me attributed the applicant's hip condition to heavy lifting rather than the types of movement described by the applicant in respect of his inspection duties. As I understand it, that finding was not called into question by the Full Court. 24 The AAT then referred to [78] of its reasons for the first decision in which it summarised some of the research studies referred to in the expert medical reports in evidence at the initial hearing. It rejected Mr Smith's objection (which was made only in the second AAT proceedings) to the relevance of those research studies and it cross-referred to [79] of the reasons for the first decision in which the relevance of the research studies and expert medical reports concerning the relationship between heavy lifting and hip osteoarthritis was discussed (see [12] above). 25 In [11] of its reasons for its second decision, the AAT explained why it again reaffirmed Comcare's decision that it had no liability to pay compensation to Mr Smith under s 14 of the SRC Act: In the initial hearing, I had before me the evidence of the applicant's duties from 1983 to 1993 at Forbes and Wagga. On that evidence and on that relating to his subsequent duties, I am satisfied that there was no material contribution from that employment to the aggravation of the applicant's osteoarthritis of the hip and that, accordingly, that ailment is not a disease or injury as those terms are defined in s 4 of the Act. It follows that there is no liability under s 14 of the Act for Comcare to pay compensation to the applicant for that ailment. 26 (f) Review of the AAT's second decision by the Federal Court: In the Federal Court, again under s 44 of the AAT, Mr Smith challenged the AAT's second decision. The questions of law raised in the appeal were as follows: 1. Whether the Tribunal failed to address itself to, consider and determine the issue for determination before the Tribunal, namely whether the aggravation of the applicant's hip osteoarthritis ("the applicant's condition") was contributed to in a material degree by the applicant's employment by the Commonwealth. 2. Whether there was evidence to support the Tribunal's finding that the applicant's condition was not a disease or injury under the Safety Rehabilitation and Compensation Act 1988 ("the Act") and that there was no material contribution from the applicant's Commonwealth employment to the applicant's condition. 3. Whether the Tribunal failed to take into account relevant evidence. 4. Whether the Tribunal failed to comply with its duty to give reasons. 27 The primary judge's reasons for rejecting Mr Smith's second application for review may be summarised as follows. 28 First, the primary judge described as "fundamental" to the disposition of the appeal the effect of the orders made by the Full Court. His Honour noted at [65] that, in construing such orders, it is generally permissible to have regard to context and particularly to the reasons for judgment associated with the orders. His Honour described this as "one of the rare cases, referred to in Peacock v Repatriation Commission [2007] FCAFC 156; (2007) 161 FCR 256 at [18], in which a limitation in the remittal is to be inferred from the reasons for judgment given by the remitting court". 29 Adopting that approach to the construction of the Full Court's orders, the primary judge found at [66]: In my opinion, the orders made by the Full Court did not require the Tribunal to rehear the application, in the sense that the Tribunal was not required to reconsider the entirety of the material before it. What had been identified was an error of law in deciding the s 7(4) question, the time of sustaining the injury, before deciding the s 14 question, the existence of the injury. The Full Court was not persuaded that the error was immaterial because the error may have had the consequence that the Tribunal had not given attention to the applicant's case about his working conditions over the whole of the period from 1983: it was not sufficiently clear that the Tribunal had in fact assessed the whole period from 1983 onwards. This was evident particularly in [81] of the 2011 reasons and the reference in that paragraph to 1997. 30 The primary judge held that the Full Court's orders required the AAT to determine initially whether or not in the AAT's first decision it considered the whole of the period of Mr Smith's employment and, only if it determined that it had not considered the whole of the period, was it required to go further. 31 Secondly, his Honour found that it was not appropriate to read the AAT's reasons for its second decision without regard to the reasons for its first decision and that, in its reasons for its second decision, the AAT had referred extensively to its first set of reasons. His Honour concluded that the orders made by the Full Court were different in character from the orders made in Minister for Immigration and Multicultural Affairs v Wang [2003] HCA 11; (2003) 215 CLR 518 (Wang), upon which Mr Smith heavily relied. In Wang, the effect of the orders made required the Refugee Review Tribunal (RRT) to carry out its task afresh: while accepting that the RRT was not bound by its earlier findings, on the remitter the RRT could adopt findings from its first review if they were unaffected by the errors or errors of law identified by the reviewing court (see at [68] and [74] per Gummow and Hayne JJ). 32 In [71], the primary judge described why he viewed the orders made by the Full Court here as different from those in Wang: In the present case, the Full Court did not find that the findings of the Tribunal in its 2011 decision were affected by the error of law identified by the Full Court: it found only that in its 2011 findings the Tribunal may not have assessed the whole period. The effect of the orders of the Full Court was, in part, that if the Tribunal had considered the whole period in its 2011 reasons then the Tribunal should make clear that it had done so. To that extent, the orders may be characterised as of the same nature as an order that the Tribunal give fuller reasons. 33 Accordingly, his Honour rejected Mr Smith's argument that Wang required the AAT to start afresh and that it was not legally permissible for it, in making its second decision, to adopt findings it had made in its first decision. 34 Thirdly, the primary judge described Mr Smith's complaint that the AAT had failed to address the correct question in its second decision as involving two propositions, both of which were rejected. The first centred on the "legal status" of the AAT's first set of reasons. His Honour found that the AAT was entitled on the remittal to take into account its first decision and findings and that such a course was inherent in the Full Court's orders. His Honour did not accept that this meant that the AAT's second decision was inevitably flawed because of its dependency on its earlier reasons which were said by Mr Smith to be tainted by the error of law found by the Full Court. In particular, his Honour did not accept that [79] and [81] of those reasons were affected by that error of law. 35 The second proposition was that the medical research studies to which the AAT had regard were not concerned with aggravation of hip osteoarthritis but rather were all concerned with causes of hip osteoarthritis in an occupational setting. His Honour found that even if that were the case it did not mean that the AAT had failed to address itself to and determine whether the aggravation was contributed to in a material degree by Mr Smith's employment by the Commonwealth. It was the expert medical witnesses who referred to those research studies and their reports, including that of Dr Browne, were considered and assessed by the AAT. 36 Fourthly, as to Mr Smith's contention that there was no evidence to support the AAT's finding that Mr Smith's condition was not a disease or injury for the purposes of the SRC Act and that there was no material contribution from his employment to his condition, his Honour described this challenge as involving "an impermissible attack on the merits of the decision" and he rejected it. 37 Fifthly, as to Mr Smith's complaint that the AAT failed to take into account relevant evidence, namely that of Dr Browne, his Honour found that once the AAT's two sets of reasons were read together, "it is clear that the Tribunal did take into account the evidence of Dr Browne and gave its reasons for not accepting that evidence". 38 Finally, as to the complaint that the AAT failed to comply with its statutory obligation to give reasons for its decision, his Honour found that that obligation was discharged by the reasons given by the AAT for its first and second decisions, when those reasons were read together.

The current appeal to the Full Court 39 Mr Smith now appeals from the primary judge's judgment on the following grounds (errors in the original): 1. Erred in concluding that the orders of the Full Court did not require that Tribunal to consider afresh the appellant's application for compensation under the Safety Rehabilitation & Compensation Act 1988 (the SRC Act) (ground 1). 2. Erred in concluding that the orders of the Full Court require the Tribunal to first consider whether it had considered the whole of the period of the applicant's employment in its First Decision (ground 2). 3. The Court should have concluded that the finding of the Tribunal in its First Decision was tainted or possibly tainted by the error of law found by the Full Court (ground 3). 4. The Court misconstrued the judgment of the Full Court to conclude that the error found by the Full Court in the Tribunal's first decision was limited to whether the Tribunal took into account the whole of the appellant's Commonwealth employment to determine liability under the SRC Act (ground 4). 5. The Court should have concluded that the Tribunal: (a) did not consider the question of the contribution of the Appellant's Commonwealth employment to the aggravation of the appellant's hip osteoarthritis (ground 5(a)); (b) limited, or may have limited, its consideration to the appellant's condition as taken to have been sustained in the 1997 (ground 5(b)). 40 The grounds of appeal substantially overlap.

The parties' submissions summarised 41 It is convenient to outline the parties' respective submissions in the order in which they were addressed in their respective written outlines. 42 In support of ground 4, Mr Smith contended that the primary judge misconstrued the Full Court's judgment by limiting the operative relevant error found by the Full Court with respect to the AAT's first decision to the question of whether the AAT had considered the whole period of Mr Smith's employment, pointing to [68] and [71] of his Honour's reasons for judgment. Mr Smith contended that the error of law identified by the Full Court was that the AAT had made a premature and (having regard to its ultimate conclusion on liability) inconsistent finding pursuant to s 7(4) of the SRC Act that the relevant disease had occurred in 1997. Mr Smith claimed that the error tainted "the whole framework of the AAT's analysis of the evidence so far as the question of material contribution to a disease was directed towards a disease which occurred in 1997", which itself created a risk that if the AAT's analytical framework and focus was upon whether there was material contribution to a disease in 1997, the whole period from 1983 onwards had not been properly assessed. 43 Mr Smith identified [81] of the reasons for the AAT's first decision as giving rise to particular concern because it referred to the period immediately preceding 1997. He further contended that, while events which occurred after 1987 were referred to in the reasons for that decision, "they were not the focus of detailed analysis", which suggested, he contended, that the AAT's focus was on the question of contribution to a 1997 ailment. Accordingly, he contended that even if in its first decision the AAT did in fact consider the whole period of Mr Smith's employment, "it would still have erred if it considered the question of material contribution only by reference to a 1997 ailment". 44 Comcare submitted that the primary judge had not misconstrued the Full Court's judgment. In particular, having regard to his Honour's reasons for judgment, Comcare submitted that: (a) the primary judge was aware that the whole period of Mr Smith's Commonwealth employment spanned the period from 1983 to 2008 (while noting that the case put to the AAT on remittal was limited to the period from 1983 to 1993 in accordance with Mr Smith's then stated position); (b) the entirety of the key passages from the Full Court's reasons were reproduced by the primary judge; and (c) his Honour noted that: (i) the Full Court identified an error of law in the AAT's first decision in deciding the s 7(4) question (the time of sustaining the injury) before deciding the s 14 question (the existence of the injury); (ii) the Full Court was not persuaded that the error was immaterial because the error may have had the consequence that the AAT had not given attention to Mr Smith's working conditions over the whole of the period from 1983; and (iii) the Full Court concluded that it was not sufficiently clear that the AAT had in fact assessed the whole period from 1983 onward and the matter was remitted so that the AAT could give "further attention" to the question of whether the requirements of s 14 were satisfied having regard to Mr Smith's employment from 1983 to 2008 (subsequently confined by Mr Smith to 1983 to 1993). 45 Comcare submitted that any "fair reading" of the Full Court's reasons demonstrated that the operative error it identified in the AAT's first decision was limited to the question of whether the AAT had assessed the whole period of Mr Smith's Commonwealth employment for the purposes of making a determination of liability under s 14 of the SRC Act. 46 As to ground 1 of the appeal (which Mr Smith said also subsumed ground 2), Mr Smith contended that the primary judge had mischaracterised the effect of the Full Court's order in holding that a rehearing was not necessary to consider afresh Mr Smith's application for compensation and that the remittal was more limited. In particular, he contended that the primary judge erred in characterising the effect of the Full Court's remittal order as requiring only that the AAT indicate whether it had considered the whole of the period from 1983 to 2008 and, if it had, to go no further. Mr Smith contended that there needed to be further attention to the question of whether s 14 was satisfied having regard to Mr Smith's employment from 1983 to 2008 (presumably now conferred to the period 1983 to 1993 which was the basis on which Mr Smith asked the AAT to determine the remittal). 47 Comcare emphasised that the Full Court did not impose any conditions on the AAT's conduct of the remittal. However, it emphasised that the Full Court effectively said that the AAT should give "further attention" to the question of whether s 14 was satisfied having regard to Mr Smith's employment from 1983 to 2008. This, in Comcare's submission, did not necessarily require another hearing de novo: the Full Court had observed at [40] that it could not see why further evidence would be necessary or appropriate. Comcare also emphasised that the Full Court did not make an order setting aside the AAT's first decision. In all these circumstances, Comcare contended that the primary judge did not err in regarding the remittal order as requiring no more than the limited rehearing which took place, which essentially involved the AAT referring to the reasons for its first decision and the evidence and other material on which the findings in that decision were based. 48 Comcare also added that, in any event, the reasons for both the AAT's first and second decisions adequately established that the AAT gave attention to the relevant question, namely whether s 14 was satisfied having regard to Mr Smith's employment from 1983 to 2008 (subsequently confined by him to the period from 1983 to 1993). Furthermore, even if ground 1 was made out, Comcare submitted that no prejudicial error was demonstrated in the primary judge's approach and, therefore, ground 1 lacked utility. 49 In support of ground 3, Mr Smith submitted that the primary judge erred in holding that the findings of the AAT in its first decision were not tainted or possibly tainted by error of law such that they could be adopted without further consideration in the AAT's second decision. That is because, so Mr Smith submitted, those findings and the AAT's approach were either skewed or possibly skewed by the erroneous legal framework which the AAT adopted in its first decision, namely posing the question by reference to a disease said to have first occurred in 1997. 50 Comcare responded by submitting that the Full Court did not conclude that the entire line of inquiry adopted by the AAT in its first decision was skewed by the identified error of law, as is reflected in the Full Court's use of provisional language such as "might" and "possibility". The Full Court did not hold that the error of law definitely impacted upon the first decision. Indeed, Comcare submitted, the Full Court acknowledged the possibility that the AAT may have reached the right result on the merits (see [4] of Buchanan J's reasons). Furthermore, Comcare submitted that, in its second decision, the AAT simply relied on relevant aspects of its first decision in the context of accurately and appropriately analysing the Full Court's orders and reasons for judgment. 51 Ground 5 has two elements. The first relates to the claim that the primary judge should have concluded that the AAT did not consider the question of a contribution of Mr Smith's Commonwealth employment to the aggravation of his hip osteoarthritis. Mr Smith had contended on the remittal that the various medical research studies had no relevance because they were concerned with the causes of his osteoarthritis rather than the aggravation of that condition and, in rejecting his objection to that evidence, he submitted that the AAT merely repeated and relied upon those medical studies without addressing the complaint that a distinction had to be drawn between the cause of his osteoarthritis and its aggravation. Mr Smith argued that the primary judge erred in [80] of his reasons for judgment in finding that there was no error even if the studies were not concerned with aggravation of his hip osteoarthritis. 52 In response, Comcare contended that the primary judge did not err in concluding that the AAT had addressed the question of aggravation in its second decision. Comcare also submitted that it was open to the AAT to rely on all of the available evidence, including the medical studies which addressed the question of, among other things, what kind of activities affected the development of, or had an association with, hip osteoarthritis. 53 The second element of ground 5 relates to Mr Smith's contention that the primary judge ought to have concluded that the AAT in its second decision limited, or may have limited, its consideration to Mr Smith's condition as taken to have been sustained in 1997. Mr Smith pointed to [3] of the reasons for the AAT's second decision and its summary of the effect of the Full Court's ruling that the error in the AAT's first decision meant that the AAT "may have been distracted by its finding that the ailment had its onset in 1997 and may only have considered such contribution during the few years prior to 1997" (emphasis added). He contended that this suggested that the AAT continued erroneously to view its task as assessing whether Mr Smith's employment had contributed to a disease only in 1997. He further submitted that the AAT's reference in [11] of its reasons for its second decision, that it took into account the whole of Mr Smith's employment, also left unclear whether, insofar as material contribution was concerned, the AAT limited its analysis to an ailment sustained in 1997. 54 In response, Comcare submitted that Mr Smith carried the burden of demonstrating appealable error on the part of the primary judge and that it was insufficient in this context merely to suggest that the AAT "may" or "might have" erred in the way contended for by Mr Smith and then to criticise the primary judge for not finding relevant appealable error for the purposes of s 44 of the AAT Act. Furthermore, Comcare submitted that, on a fair reading of the reasons for the AAT's second decision, "it is clear that the mischief that the Tribunal sought to correct was the perception that it might, or might possibly, have limited its consideration of the appellant's employment to the years prior to 1997". It contended that the AAT adequately addressed those provisional concerns by considering Mr Smith's work duties during the relevant period i.e. 1983 to 1993, in finding that his employment during that period did not materially contribute to the aggravation of his condition.

Determination of the appeal 55 It is again convenient to deal with the grounds of appeal in the order in which they were addressed by the parties.

Ground 4 56 For the following reasons, we are not satisfied that the appellant has established that the primary judge misconstrued the Full Court's judgment in his Honour's description in [71] of his reasons for judgment (see [31] above). That paragraph is directed to explaining why his Honour rejected Mr Smith's strong reliance on Wang. His Honour emphasised that: (a) the Full Court did not conclude that the findings of the AAT in its first decision were affected by the error of law identified by the Full Court (namely making a finding about a matter which arose under s 7(4) of the SRC Act without any proper foundation, whether by way of prior finding of fact for the purpose of s 14 or by way of assumption); and (b) the Full Court concluded that, in the first AAT decision, the Tribunal may not have assessed the whole period of Mr Smith's employment by the Commonwealth in determining the issue of liability under s 14 of the SRC Act. 57 In our respectful opinion, the primary judge's description of the Full Court's findings in [71] of his Honour's reasons for judgment accurately reflects the relevant parts of Buchanan J's reasons for judgment. Buchanan J described the AAT's error in [35] of his Honour's reasons for judgment (see [16] above). That error was to make a finding in respect of s 7(4) of the SRC Act (i.e. the date of "onset" of Mr Smith's symptoms of the aggravation of his osteoarthritis, which the AAT found in [63] of the reasons for its first decision should be deemed to be 1997 because that was when Mr Smith was given an injection to his hip). The AAT's attention in its first decision to the s 7(4) issue was described by Buchanan J as "premature and unnecessary", as well as ultimately contrary to its own findings on liability, because the issue presented by the provision only arises in a case such as Mr Smith's where there is a finding that the aggravation of his hip condition was attributable to his employment with the Commonwealth when that matter was viewed over the whole period of his Commonwealth employment (i.e. since 1983) and not merely as at 1997 or "a few" years immediately prior to that date. 58 Furthermore, in our opinion, the primary judge was correct to describe the effect of the Full Court's judgment as requiring the AAT to give fuller reasons if it were the fact that it had considered the whole period of Mr Smith's employment by the Commonwealth. 59 Having identified the relevant error of law, Buchanan J described the next issue as whether the error was material in the sense of rendering the AAT's findings of fact to be potentially unsafe or incomplete. As Buchanan J pointed out at [30], the primary judge in the first Federal Court decision had proceeded on the basis that, if the AAT had committed an error of law, it did not affect the AAT's ultimate conclusion. However, a majority of the Full Court disagreed with that approach. As Buchanan J explained in [38] and [39] of his Honour's reasons for judgment: (a) it was not "sufficiently clear" that the AAT did, in fact, assess the whole period from 1977 to 2008 in determining the question of liability under s 14 and there was a possibility that it was deflected from doing so by focusing on that aspect of the medical evidence which indicated that the aggravation of Mr Smith's hip condition was confined to events only a few years prior to 1997 and not the whole period from at least 1983; and (b) there was a reasonable possibility that the AAT's error in respect of the s 7(4) question "might have sent it on the wrong line of enquiry about the issues arising under s 14", a concern which his Honour found was supported by the contents of [81] of the reasons for the AAT's first decision. 60 In addition, at [28] of Buchanan J's reasons for judgment, in describing as "certainly contestable" Mr Smith's contention that the AAT had not given attention to his working conditions over the whole of the period from 1983, his Honour observed that, in its first decision, the AAT had in fact evaluated the whole of the period of Mr Smith's work at Wagga from 1987, but may not have considered his time at Forbes between the period 1983 and 1987, because there was no reference in the AAT's reasons for decision to his work at that abattoir during that period. 61 In our view, Mr Smith has failed to establish appealable error in the primary judge's understanding of the effect of the Full Court judgment. In the present case, the submission for Mr Smith that the primary judge erred by not distinguishing between the legal error as found and the consequences of that error is unsustainable. The legal error found by the Full Court was operative only because of the inability to exclude its potential consequences. But for that inability, the error necessarily would have been immaterial, and the appeal to the Full Court would have been dismissed. The warnings in Wang at [73]-[74] about the difficulty of "disentangling findings of fact" from legal error are not engaged in the (unusual) circumstances of the present case. Furthermore, we consider that his Honour was correct to reject Mr Smith's contention that, on the remittal, the AAT conducted the proceedings otherwise than in accordance with the Full Court judgment. The AAT correctly described the relevant error in its first decision as identified by the Full Court in [3] of the reasons for its second decision (see [21] above).

Ground 1 62 Mr Smith complains that the primary judge erred in taking the view that the orders of the Full Court did not require the AAT to consider afresh his application for compensation under the SRC Act. 63 For the reasons given above, we do not consider that the primary judge misconstrued the Full Court's judgment or orders. In our view, his Honour correctly understood the effect of the Full Court's orders as requiring the AAT to turn its mind to the question posed by s 14, namely whether Mr Smith's employment by the Commonwealth for the period commencing 1983 onwards contributed to the aggravation of his hip condition, and not to simply confine its consideration to either 1997 or the few years immediately preceding that date as the AAT may have done in its first decision. 64 As the primary judge made clear in [68] of his reasons for judgment, he was satisfied from the reasons for the AAT's second decision that the AAT had considered the whole of the relevant period (i.e. 1983 to 1993 as confined by Mr Smith on the remittal). In other words, in the reasons for its second decision, the AAT clarified that it had taken into account Mr Smith's working conditions and duties both at Forbes during the period 1983 to 1987, as well as those in Wagga from 1987 onwards (see, in particular, [8] and [11] of those reasons). 65 In our view, no appealable error has been demonstrated in respect of this aspect of the primary judge's reasoning.

Ground 3 66 This ground appears to be predicated on the proposition that the primary judge misconstrued the Full Court's judgment, in particular, in relation to the question of the potential effect of the error of law as identified by the Full Court. However, as is evident from the reasons above, we do not consider that the primary judge erred in the emphasis he gave to the fact that the Full Court remitted the matter for the primary purpose of the AAT clarifying whether or not it had in fact assessed the entirety of Mr Smith's employment with the Commonwealth from 1983 onwards in determining the issue of liability under s 14 and not simply confining itself to 1997 or a few years leading up to that date. Accordingly, this ground also fails.

Ground 5 67 As noted above, the focus of the first element of ground 5 relates to Mr Smith's unsuccessful objection at the remitted hearing to the relevance of the various medical research studies to the question of liability under s 14. He contends that those studies were concerned with the causes and not the aggravation of his hip condition and were therefore irrelevant. Mr Smith's complaint is that the primary judge erred in not finding error of law in the AAT's rejection of his objection to that evidence. 68 As the primary judge pointed out at [80] of his reasons for judgment, it was the expert medical witnesses who referred to these medical studies, including Dr Browne, who was called by Mr Smith. His Honour found that the AAT did refer to, address and consider Dr Browne's evidence. As to the AAT's rejection of Mr Smith's objection, the primary judge observed that even if it were true that the medical studies were all concerned with the causes of hip osteoarthritis and not aggravation, any such error was immaterial as it did not mean that the AAT failed to consider and determine whether the aggravation was contributed to in a material degree by Mr Smith's employment with the Commonwealth for the purposes of s 14. We do not consider that any appealable error has been demonstrated in his Honour's approach and reasoning. Indeed, we respectfully agree with it. 69 The second element of ground 5, which is outlined in [52] above, substantially overlaps with grounds 1 and 4 in contending that the primary judge erred in not accepting Mr Smith's argument that the AAT in its second decision confined its consideration and determination to whether it confined the issue of aggravation to the few years prior to 1997. 70 In our view, the primary judge was correct in rejecting this contention for substantially similar reasons as those given above in respect of grounds 1 and 4 of the appeal. In its second decision the AAT made abundantly clear that it had turned its mind to events relating to Mr Smith's work in Forbes and Wagga during the period 1983 and 1993 before concluding that his work during that period did not contribute in a material degree to aggravating his hip condition. It is equally clear from [3] of the reasons for the AAT's second decision that the AAT correctly understood the nature of the error of law identified by the Full Court in the AAT's first decision. The AAT did not err in its second decision by referring to and relying on certain paragraphs of the reasons for its first decision which were not affected by that error. The Full Court made no definitive finding that the AAT's reasons for its first decision were all tainted by the identified error. It is significant in this respect that the Full Court did not set aside the AAT's first decision (contrast the position in Morales v Minister for Immigration and Multicultural Affairs [1998] FCA 334; (1998) 82 FCR 374 at 387). We do not accept the submissions for Mr Smith that this fact is immaterial. Such an order was sought by Mr Smith, and not granted. The Full Court also required only "further consideration and determination" of the matter by the AAT. The terms of the Full Court's orders are consistent with the primary judge's decision about the meaning of those orders. 71 The appeal should be dismissed and the appellant ordered to pay the respondent's costs. I certify that the preceding seventy-one (71) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justices Jessup, Jagot and Griffiths.