Comcare v Wuth

2.1 The decisions by Comcare 39 Section 19 of the SRC Act provides that Comcare is to pay to an employee, who is incapacitated for work as a result of an injury, compensation for each week during which the employee is incapacitated. The relevant statutory formula is set out in s 8 of the SRC Act (quoted below at [44]). 40 On 23 December 2013, Comcare affirmed its decision that Ms Wuth's NWE calculated under s 8(1) of the SRC Act for the purposes of s 19 should be based on 29.4 hours work per week (or a work week comprising 4 days rather than 5 days), irrespective of the hours actually worked by Ms Wuth (the NWE reviewable decision). 41 Ms Wuth also made a claim on 19 February 2014 under ss 24 and 27 of the SRC Act for compensation for permanent impairment and non-economic loss. However, on 21 March 2014, Comcare decided that it was not liable to pay permanent impairment compensation in respect of a "chronic daily headache" under s 24, and consequently that it was not liable to pay compensation for non-economic loss under s 27 of the SRC Act. Comcare affirmed that determination on 2 July 2014 (the PI reviewable decision).

2.2 The Tribunal's decision 42 In February and July 2014, Ms Wuth applied to the Tribunal under s 64 of the SRC Act for review of the NWE reviewable decision and PI reviewable decision respectively. The Tribunal made its decision on both applications on 9 December 2015. 43 The Tribunal identified the issues on review at [14] as follows: • whether Ms Wuth's normal hours prior to the injury were 29.4 hours (four days a week) or 36.75 hours (five days a week) - that depends on how her normal hours should be determined under s 8 of the SRC Act, which affects her normal weekly earnings as calculated under that provision; and • whether Comcare is liable to pay Ms Wuth compensation for permanent impairment and non-economic loss under ss 24 and 27 of the SRC Act - that depends on: • whether she has suffered an injury that has resulted in a permanent impairment; and • if so: • whether her degree of permanent impairment can be assessed under the approved Guide, or under the AMA 5, or using clinical judgment; and • whether her degree of permanent impairment is 10% or more.

2.2.1 The Tribunal's finding on the NWE issue 44 With respect to the first issue, s 4(1) of the SRC Act defines "normal weekly earnings" to mean the normal weekly earnings of an employee calculated under s 8 of the SRC Act. Section 8(1) in turn provides that: (1) For the purposes of this Act, the normal weekly earnings of an employee (other than an employee referred to in subsection (2)) before an injury shall be calculated in relation to the relevant period under the formula: (NH × RP) + A where: NH is the average number of hours worked in each week by the employee in his or her employment during the relevant period; RP is the employee's average hourly ordinary time rate of pay during that period; and A is the average amount of any allowance payable to the employee in each week in respect of his or her employment during the relevant period, other than an allowance payable in respect of special expenses incurred, or likely to be incurred, by the employee in respect of that employment. 45 The Tribunal noted at [15] that "… the values of RP and A are agreed; only the value of NH (Ms Wuth's normal hours) is in issue." The value of RP was $42.78 per hour. 46 The Tribunal found that the "relevant period" (defined in ss 4(1) and 9(1) of the SRC Act) was 13 February 2007 to 26 February 2007, that period being "the latest period of 2 weeks before the date of the injury during which the employee was continuously employed" (Tribunal reasons at [16]). 47 The Tribunal noted that Ms Wuth's evidence was not contested and accepted her as a witness of truth (Tribunal reasons at [17]). Based upon that evidence and the documents, the Tribunal found with respect to her employment with the Department that: 18. In late 2006, Ms Wuth expected that her condition would improve within the following few months to the extent that she would be able to work five days a week. Before she moved to the Department on 27 November 2006, Ms Wuth had a discussion with the manager of the branch into which she was to move (the Branch Manager). The understanding between Ms Wuth and the Branch Manager was that Ms Wuth would commence working for the Department four days a week, and that she would increase her working hours to full-time when she was well enough to do so. She expected that that would be within a few months of commencing. Ms Wuth would not have agreed to the move if there had not been the option of her returning to full-time work. 19. The letter of offer from the Department (dated 9 November 2006) said that Ms Wuth's remuneration would be "pro-rated based on part time hours of 29.4 hours per week", which was four-fifths of a nominal full-time working week (36.75 hours). Ms Wuth accepted the offer on 14 November. 20. Ms Wuth entered into an Australian Workplace Agreement (AWA) with the Secretary of the Department. Clause 2.3 of that AWA, headed "Hours of work", relevantly provided: You are required to work ordinary hours and such reasonable additional hours as are necessary for the performance of your duties. Your ordinary hours are 36 hours and 45 minutes per week or 7 hours and 21 minutes per day, subject to any part-time arrangements agreed between you and your Manager. If you work part-time your remuneration (salary and any performance bonus) and leave entitlements will be calculated on a pro rata basis, based on the full-time ordinary hours. Your remuneration includes payment for all hours worked, including reasonable additional hours. The relevant period for the purposes of calculating the average hours you work shall be 12 months. Time Off In Lieu (TOIL) may be granted by your Manager, in consultation with the General Manager, to recognise short term additional hours worked. 21. Before she moved to the Department, Ms Wuth was working full-time for four days a week, using personal leave for the fifth day. At the Department, her salary was paid on a pro rata basis: four-fifths of a full-time salary. She did not use personal leave for the fifth day as she had done previously. 22. In late 2006, Ms Wuth worked about four-fifths of a full-time workload. In early 2007, in the lead up to the Budget, she and her colleagues were expected to work longer hours. By February 2007, and during the relevant period, Ms Wuth was working more than 36.75 hours a week - that is, more than a full-time workload. This involved her working long hours for four days a week, and sometimes working 2-3 hours on her "day off" each week. Consistent with her AWA, Ms Wuth was credited with some time off in lieu (TOIL) in recognition of the additional hours that she worked. 48 Ms Wuth submitted before the Tribunal that she was a full-time employee of the Department, even though her employment was subject to part-time arrangements agreed between her and her manager, or in the alternative, that there was an understanding that she would become a full-time employee and her hours should be calculated on the basis of the hours she might have worked but for the injury. For these reasons, Ms Wuth submitted that NWE should be calculated on the basis that she worked an average of at least 36.75 hours (5 days) a week during the relevant period. 49 The Tribunal found that Ms Wuth was a part-time employee (albeit with a shared expectation that she would eventually work full-time) who was remunerated consistently on a pro-rata basis, with access to TOIL when she worked more than her agreed part-time hours (Tribunal reasons at [34]). On this basis, the Tribunal agreed with Comcare that Ms Wuth's NWE should be calculated on the basis that she worked an average of 29.4 hours (4 days) a week during the relevant period (Tribunal reasons at [35]). In so finding, the Tribunal found that it was bound to apply s 8 of the SRC Act without regard to the possibility, or even the probability, that Ms Wuth would have become a full-time employee of the Department if she had not been injured, on the basis of the Full Court decision in Comcare v Nicolas [2014] FCAFC 122; (2014) 225 FCR 369 (Nicolas) (Tribunal reasons at [27]). In that case, the Full Court held that "[t]he task of the AAT was to examine whether the two-week period before the injury… was fairly representative of normal weekly earnings pre-injury, not to assess whether those earnings might be expected to increase in the future"(at [42] (the Court)). 50 Ms Wuth submitted in the further alternative that her average number of hours was 36.75 hours because she worked at least that many hours each week of the relevant period, even though her agreed hours were fewer. That argument was also rejected by the Tribunal. It found that her normal hours should be determined under s 8(1) having regard to her agreed hours only, and not the extra hours that she worked beyond her agreed hours during the relevant period: 31. Although she was not entitled to overtime, Ms Wuth had access to TOIL when she worked more than her agreed hours. The value of NH in s 8(1) must be determined having regard to the employee's "ordinary, non-overtime hours". So, in this review, NH should be determined having regard to Ms Wuth's agreed hours only, and not those extra hours that she worked beyond her agreed hours during the relevant period. The AWA required that Ms Wuth work those agreed hours and "reasonable additional hours", for which she would be paid a set salary. (emphasis added) 51 For these reasons, the Tribunal found that Comcare was correct to calculate Ms Wuth's NWE on the basis that she worked an average of 29.4 hours a week during the relevant period (Tribunal reasons at [35]).

2.2.2 The Tribunal's findings on the PI issue 52 With respect to the second issue before the Tribunal, subs 24(1) of the SRC Act provides that, where an injury to an employee results in a permanent impairment, Comcare is liable to pay compensation to the employee in respect of the injury. Where compensation is payable under s 24, Comcare is liable to pay additional compensation for non-economic loss in accordance with s 27. 53 Subsection 4(1) of the SRC Act defines: "impairment" to mean "the loss, the loss of the use, or the damage or malfunction, of any part of the body or of any bodily system or function or part of such system or function"; and "[p]ermanent" to mean "likely to continue indefinitely". 54 With respect to assessing whether an impairment is permanent, subs 24(2) of the SRC Act provides: (2) For the purpose of determining whether an impairment is permanent, Comcare shall have regard to: (a) the duration of the impairment; (b) the likelihood of improvement in the employee's condition; (c) whether the employee has undertaken all reasonable rehabilitative treatment for the impairment; and (d) any other relevant matters. 55 Subsections 24(4) and (5) of the SRC Act require Comcare to determine the degree of an employee's permanent impairment under the provisions of the approved Guide and to express that degree as a percentage. Where the degree of impairment however is less than 10%, Comcare is not liable to pay compensation under s 24 by virtue of subs 24(7). The approved Guide, namely, the Guide to the Assessment of the Degree of Permanent Impairment, is a legislative instrument binding on Comcare and the Tribunal by virtue of subs 28(4) of the SRC Act. The applicable version of the approved Guide was edition 2.1 (Tribunal reasons at [45]). 56 In assessing permanent impairment, the Tribunal took into account several medical reports, including from Associate Professor Owen White, a neurologist, on which Ms Wuth relied, and Dr Janaka Seneviratne, a consultant neurologist and clinical neurophysiologist, on which Comcare relied (Tribunal reasons at [39]-[40] and [58]). Based upon the medical evidence, the Tribunal found that Ms Wuth had suffered an injury which was contributed to in a significant degree by her employment and resulted in a permanent impairment for the purposes of s 24(1) of the SRC Act (Tribunal reasons at [42]-[43]). 57 The Tribunal found that, as Ms Wuth's claim was not defence-related, only Part 1 of the approved Guide applied (Tribunal reasons at [46]-[48]). However, the Tribunal found at [48] that Part 1 did not deal with migraines or headaches and, as Ms Wuth and Comcare agreed, "her impairment cannot be assessed in accordance with the provisions of Part 1. The tables do not provide a meaningful and clinically reliable answer" (citing Farrell v Comcare [2015] FCA 1337 at [46] (Flick J)). 58 The Tribunal then set out the parties' contentions as to the applicability of the AMA5 as follows: 50. Ms Wuth says that the AMA 5 does not provide impairment ratings for her condition. … Accordingly, Ms Wuth says, the degree of her whole person impairment should be assessed using clinical judgment. She says that that would result in an assessment of at least 10% impairment, which would mean that Comcare is liable to pay her compensation under s 24 of the SRC Act. 51. Comcare says that Ms Wuth's impairment can be assessed under the AMA 5, so clinical judgment is not to be used. Comcare says that, applying the AMA 5, Ms Wuth's degree of impairment is no more than 3%, so Comcare is not liable to pay her compensation under s 24. 59 Specifically, Comcare submitted before the Tribunal that Ms Wuth's impairment should be assessed under Chapter 18 of the AMA5, which included a protocol for assessing pain related impairment pursuant to which an examiner may award quantitative pain related impairment subject, in Comcare's submission, to a cap of 3%. 60 The Tribunal accepted at [57] that "Ms Wuth's impairment is of a kind that cannot be assessed in accordance with the provisions of Part 1 of the approved Guide, and the AMA 5 does not provide impairment rating for her condition. The degree of Ms Wuth's whole person [i]mpairment must be assessed (as the AMA 5 suggests) using clinical judgment." 61 The Tribunal then noted that Associate Professor White was of the view that in the absence of any other applicable table, it would be tenable to assess Ms Wuth with a whole person impairment of 10% under Table 12.5.3 of Part 1 of the approved guide, which is about the trigeminal nerve. Associate Professor White's evidence was that it might also be possible to apply Chapter 18 of the AMA5. On this basis Associate Professor White assessed Ms Wuth's impairment class as moderate (Tribunal reasons at [60]). Dr Seneviratne considered that the approved guide was not applicable to Ms Wuth and instead applied Chapter 18 of the AMA5, arriving at an impairment class of mild. Dr Seneviratne's calculation of this assessment was corrected in closing submissions before the Tribunal, with the result that his evidence was also that the proper impairment class was moderate (Tribunal's reasons at [61]). 62 The Tribunal however found that neither the approved Guide nor the AMA5 could be used to assess the degree of Ms Wuth's impairment. In the critical passage of its reasons, the Tribunal found: 63. Using clinical judgment to determine the degree of Ms Wuth's impairment involves comparing the impairment resulting from her headaches to impairment resulting from similar conditions with similar impairment of function in performing activities of daily living. [FN59] The table in the AMA 5 for rating impairment of consciousness and awareness assigns 0%-14% impairment ("Class 1") for "minimal limitation" and 15%-39% ("Class 2") for "moderate limitation" in performance activities of daily living. [FN60] The table for rating impairment due to episodic loss of consciousness or awareness assigns 0%-14% impairment ("Class 1") for a disorder that "limits daily activities" and 15%-29% ("Class 2") for a disorder that "interferes with some daily activities". [FN61] Of the conditions for which the AMA 5 provides impairment ratings, these are, I believe, the conditions that are most similar to Ms Wuth's and with the most similar impairment of function in performing activities of daily living. Comparing her impairment with impairment resulting from those two conditions, I think that Ms Wuth's level of impairment is analogous to the upper end of Class 1 for each condition. It is possible that her impairment is analogous to Class 2 for each condition, but there is not sufficient evidence before me to make such a finding. 63 Footnote 59 above referred to the passage in the AMA5 which is quoted below at [94], while footnotes 60 and 61 referred to Tables 13.2 and 13.3 respectively of the AMA5. 64 The Tribunal concluded that: 64. Having regard to the medical evidence before me, I make the following finding, on the balance of probabilities: Ms Wuth's degree of whole person impairment, assessed using clinical judgment, is 14%. 65 In making this finding, the Tribunal noted at [65] that: Even though the reports of Associate Professor White and Dr Seneviratne are of limited assistance in determining the degree of Ms Wuth's whole person impairment, this finding is not inconsistent with those reports. Associate Professor White concluded that the degree of impairment was 10%, impermissibly applying Table 12.5.3 of Part 1 of the approved Guide. Dr Seneviratne, in his first report, said that Ms Wuth's impairment had "adverse effects on her lifestyle, day-to-day life and work capacity" and that she had "no work capacity for pre-injury duties" 66 The Tribunal also noted at [65] that the fact that Ms Wuth is incapacitated for work is consistent with a finding of a degree of impairment of at least 14% and that, while Part 2 of the approved Guide only applies to defence-related claims and not to the present claim, the finding made by the Tribunal was consistent with the application of the approved Guide to defence-related claims for similar conditions.

2.3 The decision of the primary judge 67 By a notice of appeal filed in the Federal Court on 5 January 2016, Comcare appealed the PI reviewable decision on a question of law under s 44 of the AAT Act. Comcare identified several questions of law, namely, whether the Tribunal had misconstrued Chapter 18 of the AMA5, misconstrued and misapplied the clinical judgment impairment evaluation method provided by the AMA5, denied Comcare procedural fairness, and taken into account irrelevant considerations. 68 Ms Wuth cross-appealed the Tribunal's decision affirming the NWE reviewable decision. 69 The primary judge upheld Ms Wuth's cross-appeal, holding that the Tribunal erred in failing to use 36.75 hours as the actual average number of hours worked to calculate Ms Wuth's NWE, in accordance with s 8(1) of the SRC Act (Wuth (FCA) at [27]). In this regard, his Honour found that there was no dispute that Ms Wuth was paid for only 29.4 hours work a week, including in the relevant period; nor that she did not expect to be paid for the extra hours above 29.4 hours per week that she worked during the relevant period, but rather expected to receive TOIL (Wuth (FCA) at [23]-[24]). 70 Nonetheless, the primary judge held that NWE referred to the actual number of hours which Ms Wuth worked in the relevant period, being 36.75 hours, for the following reasons: 25. … the only applicable provisions in the SRC Act on which to calculate Ms Wuth's normal weekly earnings were those in ss 8(1) and 9(1). Those provisions referred not to the hours in the relevant period for which she was paid in money, but to the hours that she actually worked. The fact that Ms Wuth was content to take consideration for her labour in the form of leave (time off in lieu) for the additional hours that she worked did not mean that the statutory calculation of her normal weekly earnings could be performed by only using the 29.4 hours for which she received monetary consideration particularly in circumstances where she also received consideration in the form of TOIL. 26. The NH figure in s 8(1) applies to facts, not hypotheses. The only relevant fact that the Tribunal needed in order to ascertain the NH value in s 8(1) was the actual average number of, namely, more than 36.75, hours a week that Ms Wuth worked in the relevant two week period. In her notice of cross-appeal Ms Wuth only sought a finding that the NH figure be 36.75 hours per week based on the Tribunal's finding that in fact she worked in excess of that time during each of the two weeks in the relevant period. Accordingly, that figure should be used as the NH value in calculating her normal weekly earnings under s 8(1). 71 Comcare's appeal against the PI decision was, however, dismissed by the primary judge. 72 First, the primary judge found that it was open to the Tribunal to find that Ms Wuth's pain related impairment was unrateable under Chapter 18 of the AMA5 (Wuth (FCA) at [56]). His Honour considered that Chapter 18 contemplated that a qualitative assessment or rating can be made for a person who has only a pain related impairment which is not limited to a cap of 3%, and held that Comcare's argument to the contrary would lead to an "unreasonable and arbitrary result" (Wuth (FCA) at [66]). A challenge to these findings by Comcare in Ground 3 of the amended notice of appeal was ultimately abandoned. His Honour then found that: 67. Properly understood, the purpose of Ch 18 was to provide a qualitative assessment methodology that decision makers could use as a reasonable basis for awarding compensation, including where that depended, as under ss 24(6) and 28(4) of the SRC Act, on attributing a percentage for permanent impairment. The lay decision maker could form his, her or its own opinion as to the appropriate percentage, guided by the medical assessment, in accordance with Ch 18, of the qualitative degree and manifestation of any pain-related impairment. 73 Furthermore, his Honour found that: 76. …the approved Guide's reference to the AMA Guides for assessment of conditions of migraine or tension headaches, having regard to the principles of policy, consistency and fairness to which Dixon CJ referred in Commissioner for Railways (NSW) v Agalianos (1995) 92 CLR 390 at 397, was intended to result in a principled qualitative, not quantitative, assessment (at least in cases where no organ or body part dysfunction was involved) on which an administrative decision maker, such as Comcare or the Tribunal, could act in accordance with s 28(4) of the SRC Act to assign a percentage under s 24(6) based on a lay "clinical judgment". (emphasis added) 74 For those reasons, the primary judge found that the Tribunal did not misconstrue Chapter 18. His Honour then concluded with respect to Ground 3 of the appeal that: 78. In that context, the Tribunal was entitled to use its own "clinical judgment" or make its own assessment in accordance with Ch 18, including Step VIII in [18.3d] and Step 6 in [18.5]. The Tribunal needed no medical qualifications to do [so]. It was performing the administrative function of using the qualitative assessments by Assoc Prof White and Dr Seneviratne to arrive at its own assessment of a percentage amount of Ms Wuth's permanent impairment in accordance with ss 24(6) and 28(4) of the SRC Act. Ground (3) also fails. 75 Finally, the primary judge rejected the proposition that Comcare had been denied any procedural fairness. In this regard, his Honour found that Comcare knew that: (1) both of the medical experts had opined that Ms Wuth could not be assigned a percentage whole person impairment under the approved Guide or AMA Guides for her chronic migrainous headache pain-related impairment (Wuth (FCA) at [79]); (2) Chapter 18 of the AMA5 provided for such a situation by requiring an examiner (or, as in this case, qualified experts who gave evidence) to perform a qualitative assessment of a person's pain related impairment when that impairment could not be rated quantitatively "so that administrative agencies can make informed decisions about whether or not to compensate these individuals" (Wuth (FCA) at [79]); and (3) the Tribunal stood in Comcare's decision-making "shoes" and was required to give the correct and preferable decision on the medical evidence before it (Wuth (FCA) at [80]). 76 His Honour found that: 81 Comcare knew all of this at the hearing in which the Tribunal had to exercise its decision-making function to decide Ms Wuth's application for compensation under s 24. How Comcare could say that it did not have the opportunity to put its case as to what Ms Wuth should be awarded is shrouded in mystery. Comcare submitted to the Tribunal that she should get nothing because of its contention that the maximum percentage available was 3% and, since that was below the 10% minimum in s 24(7), her claim had to fail. Comcare knew that none of the doctors whose reports were in evidence had ascribed a percentage for her degree of impairment, but that was what Ms Wuth wanted the Tribunal to do. 82 There was no evidence from any officer of Comcare that it understood that the Tribunal was not engaged in a hearing of Ms Wuth's whole claim for a decision under s 24, including under ss 24(6) and 28(4). Ms Wuth's counsel asked the Tribunal in final submissions to make a clinical judgment. It had power under s 33(1)(c) of the AAT Act to do so, by informing "itself on any matter in such manner as it thinks appropriate". Comcare had the opportunity of being heard on the substantive issue. It did not put to the Tribunal that it should not do as counsel for Ms Wuth had sought. 83 The Tribunal's function in that context was to make a decision about the ultimate question that it had to resolve, namely what percentage should it assign under ss 24(6) and 28(4)… 77 Nor, his Honour found, had Comcare shown any practical injustice. Comcare had led no evidence as to what it might have done "had it somehow not appreciated that the role of the Tribunal was to make the very decision that ss 24(6) and 28(4) required it to make." (Wuth (FCA) at [83]). Moreover, his Honour found that "the Tribunal was not using 'clinical judgment' as an expert medical practitioner. It was using the evidence before it, including the expert evidence, to make the evaluative administrative decision where the approved Guide and the AMA Guides did not provide a quantitative value or range of values for determining the percentage degree of Ms Wuth's permanent impairment under s 24(6)" (Wuth (FCA) at [84]).

3.1 Grounds 1, 1A and 2: construction of NWE in s 8(1) of the SRC Act 78 It was not in issue that TOIL constitutes paid days off for working extra hours over the 24.9 hours that it was agreed Ms Wuth would work. As such, TOIL was earned for hours that Ms Wuth in fact worked, and was not paid in advance. As counsel for Ms Wuth submitted, by working extra hours, Ms Wuth earned time off with pay for those hours. There was, in Ms Wuth's submission, no warrant for saying that she ought not be compensated for the loss of TOIL under the beneficial scheme created by the SRC Act. Thus, in Ms Wuth's submission, the extra hours worked by her beyond those agreed counted as hours worked for the purposes of calculating NWE under s 8(1) of the SRC Act. (I note that no issue was taken with Comcare's submission that Ms Wuth was ineligible to receive overtime, and no submissions were made as to how the relevant provisions might apply where an employee was entitled to elect between receiving TOIL or overtime for extra hours worked.) 79 Comcare, however, submitted that, properly construed, the reference in s 8(1) of the SRC Act to the average number of hours worked was a reference to the average number of hours worked by the employee for which she or he was paid. In support of this construction, Comcare relied upon a number of contextual considerations. (1) First, the formula in s 8(1) of the SRC Act is used to calculate NWE for the purposes of the periodic calculation under s 19 of the SRC Act. NWE in other words was said to be the "index" by reference to which the amount of compensation is calculated. In Comcare's submission, given that this is the function of calculating NWE, it would make no sense to include hours in the component "NH" where the employee had no entitlement to remuneration, referring by analogy to the calculation of overtime. (2) Secondly, Comcare relied upon s 8(5) of the SRC Act as supporting its construction. It submitted that this provision provided an "escape clause" in circumstances where calculating NWE by reference to the preceding two weeks before the injury "would not fairly represent the weekly rate at which the employee was being paid in respect of his or her employment before the injury…". In particular, the focus in subs (5) on the weekly rate "being paid" was, in Comcare's submission, a further reason for construing "NH" in s 8(1) as a reference to paid hours of work. 80 The narrow construction of NWE in s 8 of the SRC Act for which Comcare contends should not be accepted. 81 Under established principles the starting point in the task of statutory construction is the legislative text. As Hayne, Heydon, Crennan and Kiefel JJ explained in Alcan (NT) Alumina Pty Ltd v Commissioner of Territory Revenue (Northern Territory) [2009] HCA 41; (2009) 239 CLR 27 (Alcan) at [47] "[t]he language which has actually been employed in the text of legislation is the surest guide to legislative intention". Comcare's construction lacks support in the statutory text, seeking to write words into s 8(1) of the SRC Act which do not appear. Thus, as Ms Wuth submitted, whereas s 8(1) simply provides that "NH is the average number of hours worked in each week by the employee in his or her employment during the relevant period", Comcare would add the qualifier "for which the employee received payment in money" or, alternatively, substitute the word "average" for the word "agreed". In so doing, Comcare seeks in my view to fill gaps perceived by Comcare in the legislation and to press a construction too much at odds with the words that the Parliament has chosen: Taylor v The Owners - Strata Plan No 11564 [2014] HCA 9; (2014) 253 CLR 531 at [38] (French CJ, Crennan and Bell JJ). 82 Equally, the rate of pay (RP) is simply defined in s 8(1) as "the employee's average hourly ordinary time rate of pay during [the relevant] period". As such, contrary to Ground 1A of Comcare's amended notice of appeal, it does not follow from accepting that "NH" represents an average of the actual hours worked by Ms Wuth that "RP" must be "reduced in direct proportion to any increase in NH, with the result that her [NWE] would be the same whether one used 29.4 hours or 36.75 hours (or some other figure) as NH." On a natural reading of the definition, "RP" is a fixed item. To read "RP" otherwise is again to read words into the section which do not appear. In this case, the ordinary rate of pay in the equation provided for by s 8(1) was fixed at $42.87 per hour (as evidenced by Ms Wuth's payslip for the pay period 22 February 2007 to 7 March 2007). 83 Furthermore, the purpose of the formula in subs 8(1) is to provide a means of assessing compensation by reference to the employee's average hourly ordinary time rate of pay multiplied by their average working hours during a two week period immediately before the injury. To this is added under s 8(2), compensation at the average hourly overtime rate of pay over the relevant period where the employee "is required to work overtime on a regular basis". In so providing, the Parliament has created a formula that is likely, in practical terms, to be easily applied (subject to the capacity to depart from the formulas in limited circumstances), as opposed to a more nuanced approach which might result in a more accurate assessment of compensation in the individual case. That being so, it still remains the case that the purpose of the formula, when read with s 19, is to ensure a measure of compensation which approximates the loss occasioned by a worker through injury. In those circumstances, where accuracy may be supplanted by simplicity, the purpose of the provision is not furthered by adopting either gloss upon the words enacted by the Parliament for which Comcare contends, and thereby confining the operation of the formula by reading in words which Parliament has not seen fit to include. While I would not put the position as broadly, nonetheless the statement by Burchett J in Brennan v Comcare (1994) 50 FCR 555 at 561 with respect to the SRC Act, that "[i]t would be impossible, in construing beneficial legislation, to reject the literal effect in favour of restricting the availability of the benefits", lends some further support to the construction which I prefer. This is not a case where construing the Act beneficially would strain the language of the provision or take no account of its context: Comcare v Pires [2005] FCA 747; (2005) 143 FCR 104 (Pires) at [47] (Jacobson J) (referring to Bull v Attorney-General (NSW) (1913) 17 CLR 370 at 384 (Isaacs J)). 84 Nor, in my view, is Comcare's construction assisted by reference to subs 8(4) and (5) of the SRC Act. Subsection (4) applies only where the shortness of the relevant period means that it is "impracticable" to calculate NWE by reference to the relevant period and the formula in subs (1) and (2). Subsection (5), in turn, applies where the shortness of the relevant period means that calculating NWE by reference to that period would not "fairly represent" average weekly earnings, such as where for example an employee is injured only 5 days after commencing work. As such, "[s]ection 8(4) and (5) guards against any arbitrary or plainly unfair outcome arising from the operation of s 9(1) [defining the 'relevant period']": Nicolas at [17] (the Court). It cannot be inferred from that exceptional purpose that the reference in subs 8(5) to "being paid" should govern the construction of the general rule in s 8(1) of the SRC Act. I also agree with the reasons of Flick J at [19] (which I have read in draft) as to why the decision in Nicolas does not otherwise assist Comcare's construction. 85 Finally, while the Tribunal relied by analogy at [30] upon the decision in Pires in support of its construction, that decision is distinguishable. In Pires, Jacobson J held that overtime which was not required or regular should not be factored into the calculation under s 8(1) of the SRC Act. However, that decision turned upon his Honour's construction of s 8(2) of the SRC Act as making exclusive provision for the circumstances in which NWE was to include an amount for average overtime payments over the relevant period (Pires at [37] - [43]). 86 It follows that no error has been established in the primary judge's construction of NWE in s 8 of the SRC Act and therefore in the finding that the Tribunal erred in not having regard to the fact that Ms Wuth worked no less than 36.75 hours during the relevant period. Grounds 1, 1A and 2 of the amended notice of appeal must be dismissed.

3.2 Grounds 4, 5 and 6: the Tribunal's application of the "clinical judgment" impairment evaluation method in Section 1.5, the AMA5 Guide 87 It will be recalled that Grounds 4 and 5 of the amended notice of appeal allege that the Tribunal misconstrued the "clinical judgment" impairment evaluation method, and lacked power to assess the degree of permanent impairment suffered by Ms Wuth using its own (lay) "clinical judgment". Ground 6 raises the question of whether, in so doing, the Tribunal acted in breach of procedural fairness. As to the latter, it was rightly not in issue that the Tribunal was required to comply with the requirements of procedural fairness. That said, the precise content to be given to the requirement to accord procedural fairness and the question of whether it has been breached will depend upon the facts and circumstances of the particular case, including the relevant statutory framework: SZBEL v Minister for Immigration and Multicultural and Indigenous Affairs [2006] HCA 63; (2006) 228 CLR 152 (SZBEL) at [26] (Gleeson CJ, Kirby, Hayne, Callinan and Heydon JJ). 88 Before turning to consider these grounds, I note that, both before the Tribunal and the primary judge, Comcare's arguments regarding Chapter 18 of the AMA5 and the application of Section 1.5 were intertwined. It was therefore in the context of finding that Chapter 18 of the AMA5 was intended to result in a principled qualitative (and not a quantitative) assessment, and that the Tribunal had therefore not misconstrued Chapter 18 of the AMA5, that the primary judge found that the Tribunal was entitled to use its own "clinical judgment" to assess Ms Wuth in accordance with Chapter 18 of the AMA5 (Wuth (FCA) at [76] - [79]). On appeal Comcare abandoned its argument regarding Chapter 18 of the AMA5. As a consequence, the argument regarding the Tribunal's application of "clinical judgment" assumed a different emphasis on the appeal from that before the primary judge. 89 Section 28(1) of the SRC Act provides that Comcare may prepare a Guide to the Assessment of the Degree of Permanent Impairment setting out: (a) criteria by reference to which the degree of the permanent impairment of an employee resulting from an injury shall be determined; (b) criteria by reference to which the degree of non-economic loss suffered by an employee as a result of an injury or impairment shall be determined; and (c) methods by which the degree of permanent impairment and the degree of non-economic loss, as determined under those criteria, shall be expressed as a percentage. 90 A Guide prepared under subs (1) or a variation or revocation of such a guide under subs (2) must be approved by the Minister and is a legislative instrument once so approved (subs 28(3) and (3A) of the SRC Act). Section 28(4) of the SRC Act provides that: Where Comcare, a licensee or the Administrative Appeals Tribunal is required to assess or re-assess, or review the assessment or re-assessment of, the degree of permanent impairment of an employee resulting from an injury, or the degree of non-economic loss suffered by an employee, the provisions of the approved Guide are binding on Comcare, the licensee or the Administrative Appeals Tribunal, as the case may be, in the carrying out of that assessment, re-assessment or review, and the assessment, re-assessment or review shall be made under the relevant provisions of the approved Guide. (emphasis added) 91 The use of the word "shall" makes it clear that applying the relevant provisions of an approved Guide is a mandatory obligation imposed upon Comcare and the Tribunal. 92 Under the heading "Principles of Assessment" in Part 1 of the approved Guide, Principle 12 provides that: In the event that an employee's impairment is of a kind that cannot be assessed in accordance with the provisions of Part 1 of this guide, the assessment is to be made under the American Medical Association's Guides to the Evaluation of Permanent Impairment 5th edition 2001. An assessment is not to be made using the American Medical Association's Guides to the Evaluation of Permanent Impairment for: … chronic pain conditions, except in the case of migraine or tension headaches..… Any reference in this guide to the American Medical Association's Guides to the Evaluation of Permanent Impairment is a reference to the 5th edition 2001. 93 By operation of s 14(1)(b) of the Legislation Act 2003 (Cth), as then in force, the effect of Principle 12 of the approved Guide is, relevantly, to incorporate without modification the AMA5 to cases of migraine or tension headaches. As such, as Comcare submitted, the AMA5 binds Comcare and the Tribunal in the same way as if it were a part of the approved Guide. 94 Relevantly, as earlier explained, Section 1.5 of the AMA5 provides that: In situations where impairment ratings are not provided, the Guides suggests that physicians use clinical judgment, comparing measurable impairment resulting from the unlisted condition to measurable impairment resulting from similar conditions with similar impairment of function in performing activities of daily living. 95 In "suggest[ing]" that physicians use clinical judgment, it is plain from the context that the text is not suggesting that others might use clinical judgment, but is rather a suggestion to physicians as to how they might undertake the necessary comparison in situations where no impairment ratings are provided. As such, as Comcare submits, the AMA5 permitted only a physician to use clinical judgment, and did not permit the decision-maker independently in the absence of any expert evidence to compare the unlisted condition with an allegedly similar impairment that was measurable. 96 Comcare also submitted that the Tribunal had acted in breach of procedural fairness in undertaking this comparison independently of any expert evidence. In this regard, while Ms Wuth submitted before the Tribunal that it should exercise its own clinical judgment, and indeed the Tribunal understood that the use of clinical judgment was opposed by Comcare (Tribunal reasons at [50] - [51] (quoted at [58] above)). It was not in issue that none of the medical practitioners had given evidence on any comparison between Ms Wuth's condition and Tables 13.2 and 13.3 of the AMA5, despite the Tribunal ultimately undertaking this exercise. Nor did Ms Wuth submit before the Tribunal that the clinical judgment which she urged the Tribunal to undertake should be done by reference to these tables. Furthermore, the Tribunal is not a specialist tribunal comprised of experts in the medical field; nor was there any requirement that the Tribunal be constituted by an expert in the relevant field in the present case. In those circumstances, Comcare's submission that the Tribunal acted in breach of the requirements of procedural fairness should be accepted. 97 In this regard, as Comcare submitted, the case is similar to that in Rodriguez v Telstra Corporation Ltd [2002] FCA 30; (2002) 66 ALD 579 (Rodriguez). In that case, the Tribunal had found that by September 1998 Mr Rodriguez's depressive disorder had ceased to be applicable to his employment, and was no longer an "injury" under the SRC Act. Mr Rodrigues submitted that the Tribunal, in so concluding, had substituted its own opinion for that of the medical experts or, put another way, the Tribunal's conclusion was unsupported by any evidence. In upholding the appeal, Kiefel J found that no medical expert had expressed the opinion arrived at by the Tribunal and none of the medical experts were questioned on the factual basis which underpinned the Tribunal's opinion (Rodriguez at [21]-[22]). Justice Kiefel also referred to the fact that the applicant tended to camouflage his depression, which in turn highlighted the complexity of the task as one requiring expert psychiatric evaluation (Rodriguez at [22]). Her Honour held that, "if a view is formed by a Tribunal which goes beyond the opinions expressed by the experts in evidence, fairness requires that it be disclosed and the parties permitted an opportunity to address it" (Rodriguez at [24]). This is so irrespective of whether the Tribunal member is medically qualified (Rodriguez at [24]). 98 Further, while accepting that the Tribunal is not bound by the rules of evidence and may inform itself as it thinks fit, her Honour held this does not mean that the rules of evidence are to be ignored. Rather, her Honour held that: 25. ….The more flexible procedure provided for does not justify decisions made without a basis in evidence having probative force: Pochi v Minister for Immigration and Ethnic Affairs (1979) 36 FLR 482, 492, referring to Consolidated Edison Co v National Labour Relations Board (1938) 305 US 197, 229; The King v War Pensions Entitlement Appeal Tribunal; Ex parte Bott (1933) 50 CLR 228, 256. The drawing of an inference without evidence is an error of law: Australian Broadcasting Tribunal v Bond (1990) 170 CLR 321, 355-356; Repatriation Commission v Maley (1991) 24 ALD 43 (Full Court). Similarly such error is shown when the Tribunal bases its conclusion on its own view of a matter which requires evidence. In Collector of Customs (Tasmania) v Flinders Island Community Association (1985) 60 ALR 717, 722 a Full Court of this Court held that it was unjustifiable, and therefore legally erroneous, for a Tribunal to base its conclusion upon its own understanding of traditional aboriginal concepts of community ownership and interests, in the absence of any evidence on the matter. 26. It may be said that expert evidence is sometimes over-utilised and is called in situations where an arbiter of fact is in a position to determine the matter for itself. Sometimes all that is necessary is for a method or process to be explained, so that the Court or Tribunal can then apply it to the facts it finds. On the other hand, there are cases where a whole question is, in effect, relegated to experts to give evidence upon it. This was such a case. The Tribunal was not put in a position where it could simply draw its own inferences. In an area which required an understanding of a disorder it could only receive the opinions, have the bases for them explained if they differed and apply logic to determine which were to be accepted. 99 Equally, it is plain that the Tribunal fell into error here in basing its conclusion at [64] as to the appropriate comparison upon its own views, when that was a matter requiring expert evidence. Not only in this regard does Section 1.5 of the AMA5 suggest that physicians use clinical judgment to undertake the relevant comparisons, but immediately thereafter Section 1.5 of the AMA5 explains that: The physician's judgment, based upon experience, training, skill, thoroughness in clinical evaluation, and ability to provide the Guides criteria as intended, will enable an appropriate and reproducible assessment to be made of clinical impairment. Clinical judgment, combining both the "art" and "science" of medicine, constitutes the essence of medical practice. 100 In those circumstances, as Comcare submitted, it was incumbent upon the Tribunal to follow an approach akin to that agreed between the parties on appeal and ordered by the Court in Riley v Comcare [2011] AATA 674 and applied in Roxas v Comcare [2012] AATA 747, namely, that: (i) having determined that there was no applicable Table for the applicant's impairment, the Tribunal should have referred to the Principles of Assessment in Part 1 of the Guide; (ii) those Principles provide that in the event that an employee's impairment is of a kind that cannot be assessed in accordance with the provisions of Part 1 of the Guide, the assessment is to be made under the edition of the AMA Guides; (iii) the AMA Guides provide that "in situations where impairment ratings are not provided, the Guides suggest that physicians use clinical judgement comparing measurable impairment resulting from the unlisted condition to the measurable impairment resulting from similar conditions with similar impairment of function in performing activities of daily living"; (iv) accordingly, if the tribunal is satisfied that neither guide provides a specific means by which the impairment can be assessed, the tribunal should consider evidence from doctors as to the degree of impairment suffered based on their clinical judgement (informed by considering the degree of impairment resulting from similar listed conditions in the relevant edition of the AMA Guides). 101 It is plain that the comparison between Tables 13.2 and 13.3 was ultimately a critical issue in the Tribunal's decision. However, it was not raised by the Tribunal in advance of its decision. Nor was sufficient notice given merely by an open-ended submission by Ms Wuth, made without reference to Tables 13.2 and 13.3, that the Tribunal may undertake its own clinical evaluation (see above at [58]). Equally the cryptic reference to the issue at [8.3] of Ms Wuth's submissions to the Tribunal was insufficient to give fair notice to Comcare. As such, Comcare was not afforded an opportunity to address or lead evidence on any new or changed issues arising by reason of the different basis on which the Tribunal ultimately decided the application. Yet, as McHugh J, for example, stated with respect to the rules of procedural fairness in Minister of State for Immigration and Ethnic Affairs v Teoh (1995) 183 CLR 273 at 311-312 (in dissent but in a passage approved by McHugh and Gummow JJ in Re Minister for Immigration and Multicultural and Indigenous Affairs; ex parte Lam [2003] HCA 6; (2003) 214 CLR 1 at [81]-[83] (Lam)): In the absence of a clear contrary legislative intention, those rules require a decision-maker 'to bring to a person's attention the critical issue or factor on which the administrative decision is likely to turn so that [she or] he may have an opportunity of dealing with it. See also e.g. Kioa v West (1985) 159 CLR 550 at 587 (Mason J); Saeed v Minister for Immigration and Citizenship [2010] HCA 23; (2010) 241 CLR 252 at [19] (French CJ, Gummow, Hayne, Crennan and Kiefel JJ); SZBEL at [25]-[32] (Gleeson CJ, Kirby, Hayne, Callinan and Heydon JJ); and SZSSJ v Minister for Immigration and Border Protection (No 2) [2015] FCAFC 125; (2015) 234 FCR 1 at [118] (Rares, Perram and Griffiths JJ); see also, by analogy, Seltsam Pty Ltd v Ghaleb [2005] NSWCA 208 (Seltsam) at [78] - [79] (Ipp JA (with whose reasons Mason P agreed at [2])). 102 It follows that the Tribunal should have advised the parties that it was concerned that the appropriate comparison should be undertaken by reference to Tables 13.2 and 13.3, and afforded them the opportunity to make submissions and lead expert medical evidence on the appropriateness of that comparison under the AMA5. 103 For these reasons, the primary judge, with respect, fell into error in finding that there was no breach of procedural fairness by the Tribunal. 104 Furthermore, I respectfully disagree with the primary judge's findings at [84]. Contrary to his Honour's view, I consider that no further evidence was required in order for Comcare to establish that the breach of procedural fairness resulted in a practical injustice: Lam at [37] - [38] (Gleeson CJ), [122] (Hayne J). As Comcare submitted, the Tribunal proceeded on a basis that was neither foreshadowed to Comcare, or could reasonably have been contemplated by it given that the approved Guide required evidence from a suitably qualified physician as to the appropriate comparison and that no such evidence was before the Tribunal. As such, Comcare was denied the opportunity to lead expert evidence on whether Tables 13.2 and 13.3 afforded an appropriate comparison applying the "clinical judgment" assessment methodology in Section 1.5 of the AMA5. It was therefore denied the opportunity to be heard which it ought fairly to have been given in the totality of the circumstances: Minister for Immigration and Border Protection v WZARH [2015] HCA 40; (2015) 256 CLR 326 at [55] (Gageler and Gordon JJ); see also by analogy Seltsam at [79] (Ipp JA (Mason P agreeing)). 105 Finally and in any event, as Comcare submits, it was not open to the Tribunal to undertake a clinical evaluation for itself without medical evidence on the comparison required, given the binding nature of the approved Guide, because the AMA5 (being incorporated into, and therefore part of, the approved Guide) made it clear that that process was to be undertaken by physicians.

4. CONCLUSION 106 For the reasons given above, I would therefore allow the appeal in part but reserve costs so as to afford the parties the opportunity to make short submissions. I certify that the preceding seventy-three (73) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justice Perry.