Comcare v Power

The decision-making process under the SRC and AAT Acts 10 Comcare is a body established under s 68 of the SRC Act. Its functions are largely set out in s 69. They include making determinations under the Act. A dissatisfied claimant may request a reconsideration of a determination under s 62(2) (s 61(1)) or Comcare may decide to undertake a reconsideration of its own motion (s 62(1)(a)). Provided the determination is a "reviewable decision" application may be made to the Tribunal for review of the determination (s 64). "Reviewable decision" is defined in s 60(1) to mean a decision made under s 38(4) or s 62. Consequently, each of the reconsideration determinations made in the present case was a reviewable decision for the purposes of the Act enabling Ms Power to seek merits review in the Tribunal. 11 The SRC Act imposes disclosure obligations on claimants who initiate AAT proceedings which may preclude them from adducing evidence (s 66). Generally speaking, the parties bear their own costs (s 67(1)). Nevertheless, in proceedings instituted by a claimant, if the Tribunal makes a decision varying or setting aside a reviewable decision and substituting one which is more favourable to the claimant, the Tribunal may order Comcare to pay the claimant's costs (s 67(8)). 12 The process of review is otherwise regulated by the AAT Act and Pt IV in particular. I shall return to the relevant provisions of the AAT Act later in these reasons. It is sufficient at this point to note three matters. 13 First, for the purpose of reviewing a decision, the Tribunal may exercise all the powers and discretions conferred by any relevant enactment on the maker of the decision under review: AAT Act s 43(1). Metaphorically speaking, this means that the Tribunal "stands in the shoes" of the decision-maker (Esber v Commonwealth of Australia (1992) 174 CLR 430 at 440); its task is to make the "correct or preferable" decision (Drake v Minister for Immigration and Ethnic Affairs (1979) 24 ALR 577 at 589). In the present case, they were decisions under s 62 of the SRC Act in relation to Ms Power's reconsideration applications. 14 Secondly, subject to the AAT Act and Regulations and any other enactment, the Tribunal's procedures are entirely within the Tribunal's discretion: s 33(1)(a). Proceedings must be conducted with "as little formality and technicality, and with as much expedition, as the requirements of [the] Act and of every other relevant enactment and a proper consideration of the matters before the Tribunal permit": s 33(1)(b). And the Tribunal is not bound by the rules of evidence but may inform itself on any matter in such manner as it thinks appropriate: s 33(1)(c). That means, for example, that, subject to relevance and procedural fairness, the Tribunal may have regard to unsworn statements and hearsay. Flick and Perry JJ drew particular attention to the significance of s 33(1) in their joint judgment in Sullivan v Civil Aviation Authority (2014) 226 FCR 555 at [88]. 15 Thirdly, the Tribunal is nonetheless bound to give reasons and where those reasons are given in writing, they must include the Tribunal's findings on material questions of fact and refer to the evidence or other material on which those findings were based (s 43(2B)).

The Tribunal proceeding 16 The two review applications were heard together. The issues the Tribunal considered were: (1) whether Ms Power continued to suffer the effects of the compensable injury; (2) if so, whether she was entitled to compensation for medical expenses (under s 16 of the SRC Act) or for payments for incapacity for work ("under s 19"); (3) whether Ms Power suffers from a psychological condition which was significantly contributed to by her compensable injury; and (4) if so, whether she was entitled to compensation for that condition under s 14 of the SRC Act. 17 Although the Tribunal concluded that Ms Power had exaggerated her symptoms and that her evidence was "not entirely reliable", it found in her favour on every issue, save in relation to the question of whether Comcare should make payments for incapacity for work. As the evidence on the question of incapacity was not recent, the Tribunal remitted this question to Comcare for its determination. 18 The Tribunal began its consideration with an analysis of the medical evidence called by the parties. After noting that some of that evidence was conflicting, the Tribunal set out what it said were its findings at [39]-[40]: 39 Ms Power had some degenerative changes in her L4-L5 and L5-S1 discs before the compensable injury. Those changes were asymptomatic. The compensable injury aggravated that degeneration of her spine. The effects of such an injury would normally have reduced or ceased within months of the injury, but those effects could continue for years. 40 Ms Power exaggerates her symptoms. Nonetheless (and leaving aside, for the moment, the video surveillance evidence and her fall at a shopping centre), it is possible that she still continues to suffer the effects of the compensable injury. 19 No doubt, these were findings the Tribunal made based on the medical evidence. They were not the sum total of its findings. The significance of this observation will become clear when I deal with the issues raised by the appeal. 20 The Tribunal then proceeded to analyse the surveillance evidence, which Comcare submitted disclosed that Ms Power did not then and no longer suffers from the effects of the compensable injury. 21 The surveillance was carried out on seven days between 17 December 2012 and 6 January 2013, including two consecutive days in December, and four consecutive days in January. Apparently the Tribunal was taken to some of it at the hearing and the video recordings were also provided to the medical witnesses for their consideration. The doctors' views differed on what the surveillance revealed about Ms Power's condition but the Tribunal adopted the description given by Ms Power's general practitioner, Dr Tim Watson, that it showed Ms Power "walking in various different locations, sitting, driving her vehicle, shopping, getting items out of her car, getting in and out of her car and various other menial tasks of everyday activity". 22 After considering the surveillance evidence, the accounts given by Ms Power and her fiancé relating to it, and the opinions given by the various medical practitioners as to its significance, the Tribunal set out its findings based on that evidence at [60]-[61]: 60 Ms Power regularly uses her TENS machine and Toradol. She thinks that they have efficacy beyond their actual physiological effect. Ms Power was wearing her TENS machine at all times during the video. She did not have the benefit of pain reduction due to Toradol at all times during the video. 61 Ms Power is not seen doing anything in the video that is inconsistent with her still suffering, at that time, from the effects of the compensable injury. 23 In relation to the finding in [61] the Tribunal noted (at [62]): Ms Power can be seen on the video moving in a way that suggests that she was protecting her back. I also think it is significant that, notwithstanding Dr Talbot's and Dr Stubbs's views about the video, both agreed that Ms Power does not do anything in the video that is inconsistent with Dr Talbot's assessment of her capacity to work - an assessment that he made on the basis that she was suffering from the effects of the compensable injury. 24 Dr John Talbot and Dr Geoffrey Stubbs were Comcare's witnesses. They are (or at least were at the time of the hearing) orthopaedic surgeons. 25 The Tribunal accepted (at [69]-[70]) that Ms Power had fallen in the shopping centre. It noted its earlier finding that it was possible that Ms Power continued to suffer the effects of the compensable injury and said that none of the evidence about the fall supported a conclusion that the effects of the compensable injury had ceased beforehand. Consequently, it concluded that the fall had aggravated the existing back injury, rather than being a new cause of Ms Power's back pain, and that Comcare was therefore liable to pay the medical expenses incurred in relation to that injury. 26 The Tribunal then turned to the question of whether Ms Power suffered any psychological condition which was significantly contributed to by her compensable injury. 27 The Tribunal referred to the medical evidence on this question, stated that it had considered that evidence, and made the following findings at [83]: Ms Power suffers from an adjustment disorder with mixed features of anxiety and depressed mood, with a date of injury of 18 August 2013. The pain that she experienced from the compensable injury contributed to a significant degree to her developing that adjustment disorder. 28 With respect to the second of the two findings, the Tribunal noted (at [84]) that "Dr Lewin said that Ms Power's pain was a 'more than trivial' cause of her psychological condition". The Tribunal then stated: Section 5B(3) of the SRC Act provides that "significant degree" means "a degree that is substantially more than material". I think that my finding is consistent with Dr Lewin's characterisation. 29 The Tribunal said that it followed from its findings at [83] that Ms Power was entitled to compensation for her psychological injury under s 14 of the SRC Act and that, under s 16, Comcare was required to meet the cost of her medical treatment for that injury. The Tribunal referred to its earlier decision to remit the question of compensation for incapacity for work to Comcare, noted Dr Lewin's opinion expressed in his report of 8 August 2014 that Ms Power's psychological condition was not such as to impair her capacity for work, but observed that Comcare would no doubt obtain further evidence before it made a determination.

The appeal 30 Appeals from the Tribunal lie to this Court on a question of law: AAT Act s 44(1). In its notice of appeal Comcare identified the following five questions: (1) Did the Tribunal apply illogical reasoning, or in the alternative make a legally unreasonable decision, in having made a finding that, 'it is possible that [Ms Power] continues to suffer the .effects of the compensable injury' (at [40] of the Reasons), then concluding that Ms Power continues to suffer from the effects of the compensable injury (at [72] of the Reasons)? (2) Did the Tribunal fail to state and apply the correct standard of proof in concluding that Ms Power continues to suffer from the effects of the compensable injury? (3) Did the Tribunal misconstrue, or misapply, the expression to a 'significant degree as it appears in s 5B of [SRC] Act? (4) Did the Tribunal's jurisdiction extend to being able to determine liability under s. 16 and 19 of the SRC Act in respect of the claim for the adjustment disorder injury? (5) Did the Tribunal fail to provide reasons for its decision in breach of its obligation to do so under s 43(2B) of the [AAT Act]? 31 Comcare sought orders allowing the appeal, setting aside the Tribunal's decision, remitting the matter to the Tribunal to be heard and decided again according to law, and requiring Ms Power to pay the costs of the appeal. It relied on the following grounds: (1) In circumstances where the Tribunal only found that it was 'possible' that the effects of the compensable injury were continuing, the subsequent conclusion that Ms Power continued to suffer from the effects of that injury was a product [of] illogical reasoning or was a legally unreasonable decision. (2) The Tribunal failed to identify, or apply the correct standard of proof in respect of being satisfied on the balance of probabilities, as opposed to possibilities, when it concluded that the effects of the compensable injury were continuing, having only found that it was 'possible' that those effects did so continue. (3) The Tribunal misconstrued and misapplied, the expression 'to a significant degree" as it appears in s.SB of the SRC Act in concluding (at [84] of the Reasons) that Dr Lewin's opinion that Ms Power's 'pain was more than a trivial cause of the psychological condition' was 'consistent' with that expression. (4) The Tribunal failed to provide reasons, in breach of its obligation to do so under s 43(2B) of the AA T Act, because it: a. failed to provide reasons, or adequate reasons, as to how, having found that it was only 'possible' that Ms Power still continues to suffer the effects of the compensable injury, that liability under the SRC Act continued in respect of that injury; and b. failed to provide reasons, or adequate reasons, for concluding that Dr Lewin's opinion that Ms Power's 'pain was more than a trivial cause of the psychological condition' was 'consistent' with the test of contribution 'to a significant degree'. (5) In the absence of a determination and a reviewable decision in respect of s.16 and 19 for the adjustment disorder injury the Tribunal's jurisdiction with regard to that claim was limited solely to s.14 of the SRC Act. 32 Ground 5 was not pressed. Consequently, question 4, to which it relates, falls away.

Issues on the appeal 33 The following issues arise: (1) Was the Tribunal's conclusion that Ms Power continued to suffer from the effects of the compensable injury the product of illogical reasoning or a legally unreasonable decision? (2) Did the Tribunal fail to identify or apply the correct standard of proof? (3) Did the Tribunal misconstrue the expression "to a significant degree" in s 5B of the SRC Act? (4) Did the Tribunal fail to provide reasons in breach of its obligation under s 43(2B) of the Act?

Was the Tribunal's conclusion that Ms Power continued to suffer from the effects of the compensable injury the product of illogical reasoning or a legally unreasonable decision? 34 Comcare submitted that the Tribunal erred in law because there was "no logical connection between the evidence and the inferences or conclusions drawn" (Minister for Immigration and Citizenship v SZMDS (2010) 240 CLR 611 at [135] (Crennan and Bell JJ)). Noting that the compensable injury was an aggravation of lumbar disc degeneration and that the Tribunal had found only that it was "possible" that Ms Power continued to suffer the effects of that injury, Comcare submitted, in effect, that it was illogical to conclude anything but that the effects of the compensable injury had ceased. 35 Mr Robinson SC, who appeared with Mr Whybrow for Ms Power, contended that Comcare's submissions largely amounted to an attack on the merits of the Tribunal's decision and submitted that question 1 "does not constitute a question of law". I reject the submission. Question 1 is not concerned with the merits of the decision but with its legality. If the question were answered in the affirmative, it could demonstrate that there had been a jurisdictional error: see Re Minister for Immigration and Multicultural affairs; Ex parte S20/2002 [2003] HCA 30, 73 ALD 1; SZMDS; and Minister for Immigration and Citizenship v Li (2013) 249 CLR 332. As a 5-member Full Court explained in Haritos v Commissioner of Taxation [2015] FCAFC 92; 147 ALD 265 at [202]: one of the functions of s 44 is to ensure that the tribunal stays within its jurisdiction. It follows that jurisdictional error would found a question of law under s 44. An appeal on the question whether the tribunal made a jurisdictional error in a specified respect, such as denying a party procedural fairness … would be, in our opinion, an appeal on a question of law. 36 In Haritos at [204] the Full Court construed one of the questions posed in the notice of appeal (question 4) as being: whether the tribunal's reasoning process was illogical, irrational or lacking a basis in findings or inferences of fact supported on logical grounds and thus made a decision it was not authorised to make. 37 In Haritos, however, the Full Court also observed at [213] that a conclusion that a decision involves a lack of reason or logic sufficient to amount to an error of law is not to be drawn lightly and that not every lapse in logic will be an error of law. 38 The difficulty with Comcare's submission is that it rests on the premise that the Tribunal found only that it was possible that Ms Power continued to suffer the effects of the compensable injury. I do not accept that this is so. The Tribunal's reasons must be read as a whole. They must also be read fairly, without concern for precision of language, and without regard to "some inadequacy [which might] be gleaned from the way … the reasons are expressed": Minister for Immigration and Ethnic Affairs v Wu Shan Liang (1996) 185 CLR 259 at 272. Reading the Tribunal's reasons in this way I do not accept that the Tribunal erred as Comcare alleged. 39 The Tribunal's finding at [40] was of an interim nature, based on part of the evidence. It did not take into account all the evidence. The Tribunal acknowledged as much at the time. What it said was subject to what was disclosed by the other evidence, including the surveillance evidence and the evidence concerning the fall at the shopping centre. As Ms Power argued, the finding at [40] was but a step in the reasoning process. The Tribunal's ultimate conclusion on the first question appears at [72]. It was that Ms Power continues to suffer the effects of the compensable injury. 40 So how did the Tribunal move from its finding that it was possible that Ms Power continued to suffer the effects of the compensable injury to its conclusion that she did? Is there a logical pathway? 41 First, Ms Power said in evidence that in order to be able to do all she was seen to be doing in the video, she must have been wearing her TENS machine and she must have received injections of Toradol on each of the days the video was taken. 42 The Tribunal referred (at [48]) to the evidence from Dr Peter Burgess, an orthopaedic surgeon, that a TENS machine is an electronic device that "blankets" pain, (at [52]) to Dr Stubbs' evidence that it distracted the user from the pain, and (at [53]) to the opinions of Drs Stubbs, Talbot and Watson that the TENS machine (and the Toradol) might have a placebo effect. It noted that TENS is an acronym for transcutaneous electrical nerve stimulation. It also referred to evidence from Drs Talbot and Stubbs that Toradol was a powerful non-steroidal anti-inflammatory medication, usually used in the management of post-operative pain. 43 Although the Tribunal found that Ms Power gave unreliable evidence, both about her use of the TENS machine and the frequency with which she received Toradol injections, Ms Power's fiancé, with whom the Tribunal found (at [50]) that she lived, gave evidence that he injected her with Toradol and that it appeared to give her pain relief for a day, sometimes a few days. The Tribunal noted (at [54]) Dr Stubbs' evidence that the Toradol might reduce the pain and therefore improve movement but would not affect any mechanical restrictions. 44 Secondly, although the TENS machine was not visible on the video, the Tribunal accepted (at [51]) Ms Power's evidence that she was likely to be wearing it while she was under surveillance. Indeed, at [60] the Tribunal found that she regularly used both her TENS machine and Toradol and that she was wearing her TENS machine at all times "during the video". The Tribunal did not accept Ms Power's evidence that she received an injection of Toradol on each of the days covered by the video (also at [51]). Instead, it found (at [60]) that she did not have the benefit of pain reduction due to Toradol at all times during the video. The obvious inference from this finding is that the Tribunal believed that Ms Power was in pain at least some of the time during the periods when she was under surveillance. 45 Comcare did not challenge these findings. 46 Thirdly, the Tribunal noted (at [62]) that on two separate occasions - when Ms Power squatted to pick up her shoes and when she bent her knees before brushing some crumbs off a seat before sitting down (see [57]) - that Ms Power could be seen on the video moving in such a way as to suggest that she was protecting her back. This was also Dr Burgess's opinion. Dr Burgess gave oral evidence to the effect that Ms Power's current condition was the result of the compensable injury. The Tribunal noted (at [57]) that Dr Burgess had testified that there was nothing in the video which was inconsistent with that conclusion. Importantly, Dr Burgess had examined Ms Power more than a year after the fall. The Tribunal had referred to this evidence at [26]-[27]. 47 Fourthly, the Tribunal also noted (at [62] as well) that Drs Talbot and Stubbs had agreed that Ms Power did not do anything under surveillance which was inconsistent with Dr Talbot's opinion given in his report of 2 October 2012 that Ms Power was fit to work, in administrative office duties, four hours a day with certain restrictions on driving, standing and lifting. While that report was not included in the appeal book and the Tribunal's summary of the written opinion at [32]-[33] does not make it clear, Mr Dube, who appeared for Comcare on the appeal, informed the Court that Dr Talbot's opinion at that time was that the restrictions on Ms Power's capacity to work resulted from the compensable injury. 48 Fifthly, while the Tribunal found (at [68]) that much of Ms Power's evidence concerning the fall at the shopping centre on 6 February 2013 was unreliable, and that she had not disclosed the fall to a number of doctors for almost a year, Drs Burgess and Watson both gave evidence that the fall aggravated (or would have aggravated) the compensable injury. The Tribunal concluded that Ms Power did not disclose the fall to the various doctors because she was fearful that it might affect her compensation payments (not, it might be inferred, because she had previously recovered from the compensable injury). It seems tolerably clear that the Tribunal was persuaded by what it had seen in the video that in the month before the fall Ms Power was still suffering from the effects of the compensable injury. 49 The Tribunal said (at [69]) that none of the evidence about the fall supported a conclusion that those effects had ceased before the fall. Comcare criticised this as an apparent non sequitur. But the criticism overlooks the fact that the evidence about the fall included the history given by Ms Power to her then GP, Dr Suzanne Ward, whom she consulted within days of the fall. The Tribunal referred at [64] to the notes of Ms Power's consultation with Dr Ward on 11 February 2013 in which it was recorded that Ms Power "fell over last week and now increased back pain" (emphasis added). 50 In this way it can be seen that the Tribunal reasoned from the possibility that Ms Power continued to suffer the effects of the compensable injury to the conclusion that she did and that those effects were aggravated by the fall at the shopping centre. While one could quibble with the way in which the Tribunal expressed itself at times, there is nothing illogical about its reasoning process or the conclusion itself, certainly nothing that would reveal an error of law. The failure to articulate that the conclusion recorded at [72] - that "Ms Power continues to suffer from the effects of the compensable injury …" - was reached on the balance of probabilities does not render it illogical. On the probative evidence before the Tribunal, a logical or rational decision maker could have come to the same conclusion. It was no part of Comcare's case that only one conclusion was open on the evidence. Crennan and Bell JJ observed in SZMDS at [135]: Whilst there may be varieties of illogicality and irrationality, 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. A decision might be said to be illogical or irrational if only one conclusion is open on the evidence, and the decision maker does not come to that conclusion, or if the decision to which the decision maker came was simply not open on the evidence or if there is no logical connection between the evidence and the inferences or conclusions drawn. None of these applied here. It could not be said that the reasons under consideration were unintelligible or that there was an absence of logical connection between the evidence as a whole and the reasons for the decision. 51 The same can be said here. 52 Ground 1 should be dismissed.

Did the Tribunal fail to identify or apply the correct standard of proof? 53 I turn now to consider Comcare's second question. Comcare submitted that it was not apparent anywhere in the reasons that the Tribunal understood or applied "the balance of probabilities test to the question of continuing liability". Rather, Comcare submitted that the reasons show that, having found that it was "possible" that Ms Power continued to suffer from the effects of the compensable injury, the Tribunal "did not then go on to satisfy itself, having regard to the correct standard of proof of the question before it" and therefore erred in law. 54 While some of the language the Tribunal used is troubling, I reject these submissions, too. 55 To a large extent, the reasons I have given for dismissing the first ground of appeal are sufficient to dispose of this ground, too. But there are some additional matters that call for consideration. 56 I begin with the Tribunal's remarks at [71]. There the Tribunal said: Ms Power exaggerates her symptoms and her evidence is not entirely reliable. But, as noted above, Comcare bears a practical onus of demonstrating that the effects of the compensable injury have ceased. Comcare has not discharged that onus. 57 The observation about Comcare bearing "a practical onus" is somewhat enigmatic. To speak in terms of a party having any onus of poof (whether legal or evidential) in proceedings before the Tribunal is apt to mislead. 58 It is well established that there is no such thing as a legal onus of proof in the Tribunal. As Woodward J explained in McDonald v Director-General of Social Security (1984) 1 FCR 354 at 357 the Tribunal is effectively required by s 43 of the AAT Act to put itself in the position of the administrator and, based on the material before it, to make its own decision. There is no presumption that the administrator's decision is correct: 59 The decision the subject of this ground of appeal is the decision made on 6 June 2013 on Ms Power's request for a reconsideration of Comcare's determination that she no longer suffered from the effects of the compensable injury and the determinations necessarily following from it. That decision was made under s 62 of the SRC Act, which relevantly provides: … (4) On receipt of a request, the determining authority shall reconsider the determination or cause the determination to be reconsidered by a person to whom its power under this section is delegated, being a person other than a person who made, or was involved in the making of, the determination. (5) Where a person reconsiders a determination, the person may make a decision affirming or revoking the determination or varying the determination in such manner as the person thinks fit. … 60 McDonald was concerned with a Tribunal decision to affirm a decision of a delegate of the Director-General of Social Security to cancel an invalid pension. Woodward J referred to s 33(1)(c) of the AAT Act, which, it will be recalled, provides that the Tribunal is not bound by the rules of evidence and may inform itself on any matter in such manner as it thinks fit. His Honour continued at 358: It is true that facts may be peculiarly within the knowledge of a party to an issue, and a failure by that party to produce evidence as to those facts may lead to an unfavourable inference being drawn - but it is not helpful to categorise this common-sense approach to evidence as an example of an evidential onus of proof. The same may be said of a case where a good deal of evidence pointing in one direction is before the Tribunal, and any intelligent observer could see that unless contrary material comes to light that is the way the decision is likely to go. Putting such cases to one side there can be no evidential onus of proof in proceedings before the AAT unless the relevant legislation provides for it, and in the present case the Social Security Act 1947 (Cth) does not. 61 In this case it was common ground that the SRC Act did not provide for an evidential onus. 62 In circumstances like this, Woodward J concluded (at 358): If the AAT finds itself in a state of uncertainty after considering all the available material, unable to decide a question of fact either way on the balance of probabilities, it will be necessary for it to analyse carefully the decision it is reviewing. If, for example, it is a decision whether or not to cancel a pension in the light of changed circumstances, then it has failed to achieve the statutory requirement of reaching a state of mind that the pension should be cancelled. If, on the other hand, it is a decision, to be made in the light of fresh evidence, whether or not the pension should ever have been granted in the first place, then it has failed to be satisfied that the person ever was permanently incapacitated for work. 63 Here, as Comcare acknowledged in argument, the decision the Tribunal was reviewing was whether or not to terminate Ms Power's compensation entitlements arising from the compensable injury in the light of changed circumstances. It was not reviewing a decision based on fresh evidence as to whether compensation should ever have been awarded. In a case such as this, as Woodward J explained in McDonald at 359, having considered all the available evidence, if the Tribunal was left in a state of indecision, it should have been resolved in the claimant's favour. 64 Jenkinson J approached the question of onus of proof in a similar way. At 369 his Honour stated: There is, however, in my opinion a dilemma in which either a court or an administrative authority determining rights or liabilities may find itself, for the resolution of which the same principles are applicable by each tribunal. Either tribunal may find itself unpersuaded either that a circumstance exists or that it does not exist. (The same may be said of a past or a future circumstance.) The court or the administrative authority will determine, by reference to the substantive law, whether it is the existence or the non-existence of the circumstance which is determinative of the question for decision. In this case the AAT would determine whether the Social Security Act 1947 (Cth), upon its proper construction, required that the applicant's pension be cancelled if she were found not to be permanently incapacitated for work, or required that the pension be cancelled unless she were found to be permanently incapacitated for work. In the former case the Tribunal's lack of persuasion that permanent incapacity did not exist would preclude cancellation. In the latter case the Tribunal's lack of persuasion that permanent incapacity did exist would result in cancellation. 65 Comcare did not make any formal submission that the approach taken in McDonald was wrong and should not be followed. 66 The Tribunal did not refer to McDonald. It did refer, however, to Telstra Corporation Ltd v Arden [1994] FCA 524; 20 AAR 285 and Commonwealth v Borg [1991] FCA 710. 67 In Telstra v Arden Burchett J considered that what was said in McDonald was consistent with his own statement in Reitano v Commonwealth of Australia (unreported, Evatt, Northrop and Burchett JJ, 13 December 1985) that, where the question was whether an employee who had previously been found to be entitled to compensation was no longer eligible, "the burden of persuasion be borne by the arguments against the existing entitlement of the applicant [worker]". 68 In Commonwealth v Borg the Full Court was hearing an appeal from the orders of a single judge setting aside a Tribunal decision affirming a determination by a delegate of the Commissioner for Employees' Compensation (made two years after liability had been determined in the employee's favour) to the effect that any incapacity suffered or medical expenses incurred by the employee were no longer the result of the original injury she had sustained in the course of her employment ("soft tissue injury, cervical spine and neck injury") so that liability to pay compensation had ceased. The original determination was that original injury had aggravated a pre-existing depression. In two respects, then, the case is similar to the present in that it concerned a review of a reconsideration of a determination in which liability had earlier been accepted and it involved the aggravation of a pre-existing ailment. After harking back to what he and Woodward J had said in McDonald on the question of onus, Jenkinson J (with whom Sweeney J agreed) said: I think that the Act required on its proper construction that the delegate should not make the determination he did make unless he was persuaded that one of the entitling circumstances had on or before [the date of the decision] ceased to exist. … Determinations made before [that date] had established [the employee]'s entitlement to payments in all respects except one. Those determinations had not established what the period of incapacity was: the end of the period had been left by the last determination made before [that date] to be thereafter determined by the Commissioner or his delegate. … [T]he delegate must in my opinion be persuaded as to when the time was or will be on which the period has ended or will end. Unless persuaded of that he is not in my opinion authorised by the Act to make the determination he did make, which is a determination that the period of the incapacity in which the injury resulted has ended and that any incapacity existing at the time of the determination is not an incapacity in which the injury resulted. The function of the Tribunal on review is the same. (Emphasis added.) 69 Neither of these judgments, however, used the expression apparently embraced by Comcare and adopted by the Tribunal ("a practical onus"). From what I was led to believe, it derives from a remark made by Mansfield J in Brackenreg v Comcare (2010) 187 FCR 209, to which Mr Dube drew my attention during the hearing. The expression appears once (in [61]) in the course of an exposition of the reasoning in another case. Comcare, however, relied on an extract in Brackenreg of the passage in Woodward J's reasons in McDonald at 358 (quoted at [60] above) where the expression does not appear. 70 Nonetheless, I accept that is reasonable to say, as a practical matter, that Comcare would have to persuade the Tribunal of the circumstances which justify a finding that compensation payments should no longer be made. The statement the Tribunal made in the present case that Comcare did not discharge its onus should be taken to mean that the Tribunal was not persuaded that Ms Power was no longer suffering from the effects of the compensable injury. 71 It is entirely plausible that the Tribunal found itself in the state of uncertainty to which Woodward J referred in McDonald at 358. That is, after considering all the available material, it was unable to decide either way on the balance of probabilities whether Ms Power continued to suffer the effects of the compensable injury, in which case it would have been bound to decide the matter in Ms Power's favour. In these circumstances, the statement at [40] (picked up again at [69]) that it was possible that Ms Power continued to do so might be readily understandable. But as I have already explained, the Tribunal went further, concluding that she did continue to suffer those effects. I am unable to see how it could have reached this conclusion unless it was satisfied on the balance of probabilities that Ms Power continued to suffer the effects of her compensable injury or, at least, that it was not satisfied on the balance of probabilities that she no longer did. In any case, as the Tribunal was plainly not persuaded that "one of the entitling circumstances had … ceased to exist" in that it was not persuaded that Ms Power did not continue to suffer the effects of her compensable injury, I am not satisfied that there is any substance in this ground of appeal. 72 For all these reasons I am not satisfied that the Tribunal erred in law as alleged and ground 2 of the notice of appeal must be dismissed.

Did the Tribunal misconstrue and misapply the expression in s 5B of the SRC Act: "to a significant degree"? 73 Section 5B provides: (1) In this Act: disease means: (a) an ailment suffered by an employee; or (b) an aggravation of such an ailment; that was contributed to, to a significant degree, by the employee's employment by the Commonwealth or a licensee. (2) In determining whether an ailment or aggravation was contributed to, to a significant degree, by an employee's employment by the Commonwealth or a licensee, the following matters may be taken into account: (a) the duration of the employment; (b) the nature of, and particular tasks involved in, the employment; (c) any predisposition of the employee to the ailment or aggravation; (d) any activities of the employee not related to the employment; (e) any other matters affecting the employee's health. This subsection does not limit the matters that may be taken into account. (3) In this Act: significant degree means a degree that is substantially more than material. (Original emphasis.) 74 It does not seem to have been in dispute that the adjustment disorder diagnosed by Dr Lewin was an ailment (and therefore a disease within the meaning of the Act). Nor does it seem to have been in dispute that, if it was contributed to, to a significant degree, by the compensable injury, then the adjustment disorder was compensable, too. 75 At [80] of its reasons the Tribunal made the following observations: Dr Lewin identified a number of causes of Ms Power's adjustment disorder. At the hearing, he said that her emotional response to pain was one of several contributing factors. It was not, he said, the sole cause but it was 'more than trivial'. Dr Lewin declined an invitation, from counsel for Ms Power, to say that Ms Power's pain had contributed to her psychological condition to a "significant degree" - a term used in the SRC Act. 76 As I read the Tribunal's decision, its finding that the pain from the compensable injury contributed to a significant degree to Ms Power's adjustment disorder is based (at least, in part) on Dr Lewin's evidence. The statement at [84] of the reasons that its finding is consistent with Dr Lewin's characterisation must mean that the Tribunal's construction of the definition of "significant degree" in s 5B(3) was that "a degree that is substantially more than material" is synonymous with "more than trivial". Without more, that is a misconstruction of s 5B and demonstrates that the correct test was not applied. As the Tribunal acknowledged, Dr Lewin declined to go further. In his report he noted that Comcare had asked his opinion about causation. In response he noted what Ms Power had told him but stopped short of expressing an opinion. He wrote: The first episode occurred within the context of the death of a parent and the birth of her third child by Caesarean section. The second episode occurred within the context of a marital problem. The second episode remitted once the marital problem was resolved. Ms Power reported no symptoms and no impairment of functioning in the period prior to a workplace injury in 2010. 77 Were it not for the oral evidence, that might have been enough for the Tribunal to infer that Dr Lewin's opinion was that the pain resulting from the compensable injury was the only cause of the adjustment disorder. But that inference was not open following the oral evidence. 78 A contribution to a degree that is substantially more than material must necessarily be substantially greater than one which is trivial. 79 The Tribunal's approach apparently ignores s 5B(3). It also reflects a lack of appreciation of the legislative history and the case law to which it appears it was not taken by the legal representatives of either party. 80 The SRC Act came into force in 1988. The definition of "disease" originally appeared in s 4 of the Act. Section 4 read: disease means: (a) any ailment suffered by an employee or (b) the aggravation of any such ailment; being an ailment or an aggravation that was contributed to in a material degree by the employee's employment by the Commonwealth or a licensed corporation. (Emphasis added.) 81 The SRC Act replaced the Compensation (Commonwealth Government Employees) Act 1971 (Cth) (the 1971 Act), which stipulated that the employment be "a contributing factor to the disease". It did not expressly require the contribution to be a material one. In Australian Telecommunications Commission v Treloar (1989) 90 ALR 202, which was concerned with the 1971 Act, Davies J held at 204, however, that the contribution had to be of a causal nature and therefore "causally significant or, to use another term, material". His Honour's opinion was that the new definition in the SRC Act was similar. In Treloar v Australian Telecommunications Commission (1990) 26 FCR 316 the Full Court endorsed this interpretation, observing at 323 that the insertion of the word "material" "served only to emphasise that the section is not brought into play unless it be established by evidence that features of the employment did in fact and in truth contribute to the condition complained of", and, provided the causal connection were established on the balance of probabilities, the size of the contribution did not matter. This approach was consistent with the common law jurisprudence. In Bonnington Castings Ltd v Wardlaw [1956] AC 613 at 621 Lord Reid explained the meaning of a material contribution as follows: What is a material contribution must be a question of degree. A contribution which comes within the exception de minimis non curat lex is not material, but I think that any contribution which does not fall within that exception must be material. I do not see how there can be something too large to come within the de minimis principle but yet too small to be material. 82 In other words, a material contribution is one which is greater than minimal or, one might say, trivial. 83 In Comcare v Canute (2005) 148 FCR 232 at 249, however, French and Stone JJ took issue with the application of this approach to the definition of "disease" in the SRC Act. Although their Honours accepted that a "but for" test was inappropriate, after referring to the Minister's second reading speech on the introduction of the Bill which became the SRC Act, they said: the changes brought about by the enactment of the SRC Act were intended to require that the contribution be "more than a mere contributing factor" … Content must be given to the word "material" contained in the definition of "disease" in the legislation as it presently stands. The inclusion of this term imposes an evaluative threshold below which a causal connection may be disregarded. 84 However their Honours did not consider it necessary to explain the meaning of "material" further nor to define the "evaluative threshold". It should be noted that, according to the Minister's second reading speech: Under the existing Act an employee was required to establish only that his or her employment was a contributing factor in the contraction of a disease. This test does not adequately reflect the rights and obligations of the Commonwealth and its employees in relation to work-related disease and frequently results in the Commonwealth being liable to pay compensation for diseases which have little, if any, connection with employment. This Bill seeks to remedy that situation by requiring an employee to show that his or her employment contributed in a material degree to the contraction of the disease. The Government believes that this is a test which is firm but fair and which properly reflects the balance between the interests of the Commonwealth as employer and its employees. An employee will not be required to show that his or her employment caused the disease, or even that it was the most important factor in the contraction of the disease. It is intended that the test will require an employee to demonstrate that his or her employment was more than a mere contributing factor in the contraction of the disease. Accordingly, it will be necessary for an employee to show that there is a close connection between the disease and the employment in which he or she was engaged. (Emphasis in Canute.) 85 In Comcare v Sahu-Khan (2007) 156 FCR 536 at [14] Finn J observed that the legislative history of the definition of "disease" makes it plain that the term "material" in the phrase "in a material degree" in the SRC Act was not used to denote a contribution which was only greater than de miminis. Thus, it appears that, despite the common law approach to "material contribution", the intention of the SRC Act was that the contribution of the employment to the disease of an afflicted employee had to be not just greater than trivial. In Sahu-Khan Finn J noted (at [15]) that the Shorter Oxford English Dictionary defined "materially" to include "substantially" and "considerably". 86 Even so, his Honour went on to say (at [16]): Bearing in mind that the course of statutory construction is often not aided by substituting for the word used in an enactment, another word which is not so used, probably the best that can ultimately be said is that the s 4 definition: (i) requires a stronger causal relationship between the employment and the ailment, etc suffered than that exacted by the 1971 Act; (ii) "in a material degree" requires an evaluation of all relevant contributing factors for the purpose of asking whether the employee's employment did or did not contribute materially to the suffering of the ailment, etc, in question ("the threshold evaluation"); (iii) whether this will be so in a given case will be a matter of fact and degree. 87 His Honour was not satisfied that the Tribunal had applied the correct test because it had referred to what was said by the Full Court in Treloar and there was a "lack of any obvious consideration of an evaluative threshold beyond a de minimis test" (by which I take him to mean that the Tribunal applied the Treloar test of a contribution greater than de minimis) (see [7] and [17]). 88 To similar effect, in Dunstan v Comcare [2011] FCAFC 108; 125 ALD 362 at [39] Gray and Cowdroy JJ observed that "Canute must be regarded as authority for the proposition that the intention of Parliament was to impose a more stringent test of the causal relationship between employment and disease than the Full Court in Treloar had thought". 89 Section 5B was inserted into the SRC Act by the Safety, Rehabilitation and Compensation and other Legislation Amendment Act 2007 (Cth) and commenced on 13 April 2007. The outline of the proposed changes in the Explanatory Memorandum to the Bill (EM) began with the following statement: The Bill amends the Safety, Rehabilitation and Compensation Act 1988 (SRC Act) to maintain the financial viability of the scheme - which has come under growing pressure from increasing numbers of accepted claims, longer average claim duration and higher claim costs, partly as a result of court interpretations of the legislation. 90 The first of the principal amendments identified in the EM was the amendment to the definition of "disease". Its purpose, it was said, was "to strengthen the connection between the disease and the employee's employment". One of the examples of the "court interpretations of the legislation" which was implicitly criticised was the interpretation given by the Full Court in Treloar. The Regulation Impact Statement included in the EM referred under "[d]efinition of 'disease'" to the italicised passage in the second reading speech extracted in the joint judgment in Canute (see above at [84]) and said: It was the original intention of the SRC Act that an employee's eligibility for compensation payments for a disease suffered by the employee should require a close causal connection between the employee's work and the contraction or aggravation of the disease. The causality test requires an employee's employment to have contributed in a "material degree" to the contraction or aggravation of the disease. 91 The Statement acknowledged what had been said in Canute but added that the comments made there might "reduce the erosion in the meaning" but were "yet to be tested at law". 92 Several options were canvassed and their potential impacts assessed. The option of requiring employment to make a "significant contribution" to the contraction of a disease was recommended, amongst other reasons, because it was "considered to provide a stronger causal connection between an employee's employment and the contraction or aggravation of a disease" than the existing test, even if "material degree" were defined. Concern was expressed that there was "a risk that this test would still allow for worker's compensation eligibility in cases where employment has made only a minor contribution to the illness". 93 There is no room for doubt that the purpose of the 2007 amendments was to strengthen the connection necessary between the employment and the contraction or aggravation of a disease. Including a definition of "significant" as "substantially more than material" makes this abundantly clear. In other words, it is insufficient that the contribution of the employment be "more than trivial"; it had to be substantially more than trivial. The Tribunal did not recognise this, despite its reference to the definition. The error the Tribunal made is similar to the one made by the Tribunal in Sahu-Khan. In a valiant attempt to save the decision Mr Robinson drew attention to the fact that Dr Lewin had said "certainly more than trivial", but this was no more than an emphatic way of saying "more than trivial". It did not satisfy the statutory test and the Tribunal was mistaken in thinking otherwise. 94 Moreover, the current test of contribution also requires an evaluative exercise to be undertaken. That is apparent both from the words used in subs (1) of s 5B and also the matters to which subs (2) draws attention. The Tribunal did not engage with any of them. Indeed, it did not mention subs (2) at all. While the chapeau to the subsection states that those matters "may" (not "shall") be taken into account, a word which is generally permissive, properly construed it is at least arguable that in this context it is directory; in other words that "may" means "shall": see Julius v Lord Bishop of Oxford (1880) 5 App Cas 214 at 222-223 (Earl Cairns LC); North Australian Aboriginal Justice Agency Ltd v Northern Territory [2015] HCA 41 at [209] (Nettle and Gordon JJ). In the absence of argument on this question I refrain from expressing a concluded view. Nevertheless, there is nothing in the Tribunal's reasons to indicate that it carried out the kind of evaluative exercise required by the statute. 95 There is another problem with the Tribunal's conclusions with respect to Ms Power's psychological condition. I mentioned earlier the Tribunal's reference to s 19 of the SRC Act and its decision to remit to Comcare the question of whether Ms Power has any continuing incapacity to work. There is an apparent inconsistency between on the one hand the Tribunal's remittal decision and the reasons given for it at [74]-[75] and on the other its decision to award compensation to Ms Power under s 14 of the Act with respect to her adjustment disorder. Compensation under s 14 is only payable if an injury suffered by Ms Power within the meaning of the Act results in incapacity for work or impairment. Section 19 is concerned with the amount to be paid where an injury results in incapacity. It does not come into operation until or unless a decision to that effect is made and no such decision was made. Accordingly, that aspect of the decision could not stand in any event.

Did the Tribunal fail to provide reasons in breach of its obligation under s 43(2B) of the AAT Act? 96 The Tribunal is required to give reasons (either orally or in writing): AAT Act s 43(2). Section 43(2B) provides that, where the Tribunal gives its reasons in writing, "those reasons shall include its findings on material questions of fact and a reference to the evidence or other material on which those findings were based". 97 Mr Robinson was content to assume that a failure by an administrative tribunal to provide adequate reasons is an error of law. There is authority in the Full Court to this effect: see Dornan v Riordan (1990) 24 FCR 564 at 573 and Civil Aviation Safety Authority v Central Aviation Pty Ltd (2009) 179 FCR 554. Dornan concerned an appeal against an order made under the Administrative Decisions (Judicial Review) Act 1977 (Cth) about a determination of the Pharmaceutical Benefits Remuneration Tribunal made under the National Health Act 1953 (Cth), where the statutory duty to provide reasons appeared in s 98BD. But the pendulum has swung in both directions, before and after Dornan. In Dornan at 573 the Full Court held that "a substantial failure to state reasons for a decision, in the circumstance that a statement of reasons is a requirement of the exercise under the statute of the decision-making power, constitutes an error of law". In so doing it rejected an observation to the contrary by Brennan J in his dissenting opinion in Repatriation Commission v O'Brien (1985) 155 CLR 422 at 445-446. 98 Since then, doubt has been cast on the correctness of this statement in Dornan and the reasoning process underlying it and the issue has been the subject of much debate in the authorities, beginning with Comcare v Lees (1997) 151 ALR 647 (Finkelstein J). That debate is summarised in a number of judgments, including Kennedy v Australian Fisheries Management Authority (2009) 182 FCR 411 at [60]-[75] (Tracey J) (a judgment concerning the obligation to give reasons contained in s 160(1)(b) of the Fisheries Management Act 1991 (Cth)) and Sent v Commissioner of Taxation [2012] FCA 382; 57 AAR 27 at [133]-[137] (Murphy J) (an appeal from the AAT), where views were expressed that Dornan was no longer good law. In the context of an appeal under s 44 of the AAT Act I incline to the view expressed by Mortimer J in Repatriation Commission v Holden [2014] FCA 605; 63 AAR 481 at [75] that "so long as a question of law is raised in respect of the Tribunal's alleged non-compliance with ss 43(2) and 43(2B), this Court has jurisdiction to determine the matter and exercise the powers conferred on it by s 44 of the AAT Act if it finds such a failure to have occurred". 99 In any event, in the present case I am not persuaded that there has been a failure to give reasons as required by s 43(2B). The Tribunal set out its findings on questions of fact it considered material and referred to the evidence on which those findings were based and the statement of reasons explains its "path of reasoning" in sufficient detail to enable the Court to see whether the opinion involves an error of law: Wingfoot Australia Partners Pty Ltd v Kocak (2013) 252 CLR 480 at [55]. The statement of reasons in this case meets this description. It is also sufficient to enable Comcare to understand why it lost. 100 Comcare conceded that the Tribunal was not obliged to set out its findings on every matter of fact which might objectively be considered material, referring to Minister for Immigration and Multicultural Affairs v Yusuf (2001) 206 CLR 323 (see [9]-[10] (Gleeson CJ), [33]-[34] (Gaudron J), [62]-[69] (McHugh, Gummow and Hayne JJ)). 101 Yusuf was concerned with s 430 of the Migration Act 1958 (Cth), which is in relevantly identical terms to s 43(2B) of the AAT Act. As the plurality said in Yusuf at [68] of the obligation imposed by s 430 of the Migration Act: Neither expressly nor impliedly does this section require the Tribunal to make, and then set out, some findings additional to those which it actually made. In Singh [Minister for Immigration and Multicultural Affairs v Singh (2000) 98 FCR 469], significance was attached to the use of the word "material" in s 430(1)(c). It was said that "material" in the expression "'material questions of fact" must mean "objectively material". Even if that were right, it would by no means follow that the Tribunal was bound to set out findings that it did not make. But it is not right to read "material" as providing an objective or external standard of materiality. A requirement to set out findings and reasons focuses upon the subjective thought processes of the decision-maker. All that s 430(1)(c) obliges the Tribunal to do is set out its findings on those questions of fact which it considered to be material to the decision which it made and to the reasons it had for reaching that decision. (Original emphasis.) 102 The same is true of the obligation under s 43(2B) of the AAT Act: see, for example, Smith v Comcare [2014] FCA 811; 64 AAR 204 at [90] (Robertson J); Kelly v Australian Postal Corporation [2015] FCA 1064 at [44]-[45] (Griffiths J). 103 Comcare argued, however, that: [T]he Tribunal's reasons did not explain, or set out the findings on material questions of fact for either of: 1. how, having found that it was only 'possible' that Ms Power still continues to suffer the effects of the compensable injury, that liability under the SRC Act continued in respect of that injury; and 2. concluding that Dr Lewin's opinion that Ms Power's 'pain was more than a trivial cause of the psychological condition' was 'consistent' with the test of contribution 'to a significant degree'. 104 As I have already observed, the Tribunal set out its findings on the facts it considered material to its decision. The proposition that the Tribunal did not explain how Comcare had a continuing liability for the effects of the compensable injury must be rejected for the reasons I have given above at [41]-[51] in relation to ground 1. The proposition that the Tribunal did not explain why Dr Lewin's opinion was consistent with the statutory test should also be rejected. The Tribunal's obligation under s 43(2B) was to set out the reasons for concluding that the Commonwealth's employment contributed to a significant degree to Ms Power's psychological condition. It discharged that obligation at [78]-[84]. It referred (at [81]) to Dr Watson's evidence that "the psychological condition developed as a result of the compensable injury" and at [84] to Dr Lewin's opinion, which it erroneously considered answered the statutory description. 105 Ground 4 must therefore be rejected.

Conclusion 106 Grounds 1, 2 and 4 should be dismissed but ground 3 upheld. The Tribunal's finding at [83] that the pain Ms Power experienced from the compensable injury contributed to a significant degree to her developing an adjustment disorder with mixed features of anxiety and depressed mood is infected by legal error. 107 While the Tribunal referred to Dr Watson's opinion that the psychological condition developed as a result of the compensable injury, given the significance attributed to Dr Lewin's evidence in its reasons I cannot say that it would be futile to remit the matter to the Tribunal "because if it [had] applied the proper test it would nonetheless be driven ineluctably to the same conclusion": Wiegand v Comcare Australia (No 2) [2007] FCA 237; 94 ADL 154 at [8] (Finn J). I am not satisfied that Dr Lewin's opinion and the Tribunal's erroneous construction of s 5B of the SRC Act did not influence its findings on the question of whether Ms Power's employment with the Commonwealth significantly contributed to her adjustment disorder and its ultimate conclusion that Comcare was liable to pay compensation in respect of it. 108 It follows that the appeal should be allowed in part and the matter remitted to the Tribunal but the remitter should be limited to the hearing and determination of the question whether Ms Power's adjustment disorder was significantly contributed to by her employment with the Commonwealth. Having regard to the Tribunal's view that the adjustment disorder might have an effect on Ms Power's continuing incapacity for work, the hearing and determination of the remitted question should take place before Comcare determines whether it is liable to pay compensation for incapacity for work, and if so in what weekly amounts. 109 Orders will be made to this effect. 110 That leaves the question of costs. Since Comcare has succeeded on only one of the four grounds pressed, I am of the opinion that it should recover only a proportion of its costs. Some of the preparation for the appeal, including the production of appeal books and the half day hearing, would have been necessary in any event so an order that Comcare recover costs in direct proportion to its success is probably unreasonable. Taking all relevant factors into account, I propose that Ms Power pay half of Comcare's costs. Those costs, however, should not include the costs of and incidental to the photocopying of individual pages of the Tribunal's judgment for insertion in Part C of the appeal book when the entire decision was already in Part A. Nor should they include the costs of and incidental to the preparation of a second copy of the authorities and legislation. Those costs were incurred unnecessarily, for no good reason and for no apparent purpose. They were, indeed, wasteful. 111 If either party seeks a different costs order, application should be made within 21 days accompanied by submissions not exceeding two pages. The other party will have 14 days to respond in like kind and I will decide the question on the papers. If no application is made, I will make orders in chambers to the effect of the terms I have proposed. I certify that the preceding one hundred and eleven (111) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justice Katzmann.