Szajna v Australian Postal Corporation

The legislation 11 The applicant made her claim for compensation pursuant to ss 54(1) and 55(1) of the SRC Act. The respondent was required under s 61(1A) to consider and determine the claim for compensation. After the respondent rejected the claim, the applicant requested, pursuant to s 62(2), that the respondent reconsider its determination. The respondent made a decision under s 62(5) affirming its determination. The applicant then applied to the Tribunal for review of that decision pursuant s 64(1) of the SRC Act. 12 The respondent determined that it had no liability to pay compensation because Mr Szajna had not suffered an "injury" within the meaning of that expression in ss 5A(1) and 14 of the SRC Act. Section 14 provides, relevantly: (1) Subject to this Part, Comcare is liable to pay compensation in accordance with this Act in respect of an injury suffered by an employee if the injury results in death, incapacity for work, or impairment. 13 The word "injury" is defined in s 5A(1) of the SRC Act, so far as is relevant to this case, as follows: injury means: (a) a disease suffered by an employee; or (b) an injury (other than a disease) suffered by an employee, that is a physical or mental injury arising out of, or in the course of, the employee's employment; 14 The word "disease" is then defined in s 5B(1) of the SRC Act, relevantly, as follows: disease means: (a) an ailment suffered by an employee; … that was contributed to, to a significant degree, by the employee's employment by the Commonwealth or a licensee. 15 An "ailment" is defined in s 4(1) to mean "any physical or mental ailment, disorder, defect or morbid condition (whether of sudden onset or gradual development)".

The issues placed before the Tribunal 16 In their written and oral submissions to the Tribunal, each of the parties accepted that the central question for determination was whether or not Mr Szajna's death was the result of an "injury" within s 5A(1) of the SRC Act. They also agreed that the Tribunal should determine this question by deciding whether Mr Szajna's ventricular fibrillation was the inevitable consequence of his underlying coronary artery disease. It is unclear why the parties focussed on ventricular fibrillation, rather than cardiac arrest or the interruption of blood supply to the brain (a stroke), which seem to have been more immediate causes of his death. 17 In her statement of facts and contentions, the applicant put the issue in the following way: 3.8 It can be accepted that there is a distinction between a physiological change that is "nothing more than the sole and inevitable result of the ravages of a disease" [Kavanagh v The Commonwealth (1960) 103 CLR 547 per Dixon CJ] on the one hand, and a "disturbance of the normal physiological state" [Australian Postal Corporation v Burch (1998) 156 ALR 483] or "sudden physiological change" [Kennedy Cleaning v Petkoska (2000) 200 CLR 286] on the other. … 6.1 The issue for determination is whether the ventricular fibrillation suffered by Mr Szajna on 7 February 2012 was "nothing more than the sole and inevitable result of the ravages of" his pre-existing atherosclerotic disease, or whether there was a "sudden physiological change" that amounted to an injury. If it [sic] there was a sudden physiological change, even if caused by the underlying disease, then Mr Szajna suffered an "injury" within the meaning of s.5A and his resulting death is compensable. 18 The applicant's statement of facts and contentions concluded that: 8.1 The ventricular fibrillation that caused Mr Szajna's death was a sudden physiological change that was not the sole and inevitable progression of a pre-existing condition. Accordingly it should be accepted that the cause of Mr Szajna's death was an "injury" within the meaning of s.5A and that compensation should be paid to the Applicant accordingly. 19 In its statement of facts, issues and contentions, the respondent stated: 5.4 With respect to the issue of 'inevitable consequence', it is a question of whether this man's ventricular fibrillation was the inevitable consequence of his coronary artherosclerosis or underlying disease. It is not a question of whether coronary artherosclerosis is always the cause of ventricular fibrillation. 20 The respondent contended: 5.5 …Any ventricular fibrillation resulting in death in this case was an inevitable consequence of the underlying disease process of coronary atherosclerosis. 21 In the course of the hearing, after conceding that ventricular fibrillation falls within the concept of a disturbance of the normal physiological state, counsel for the respondent said: The other issue is whether or not the ventricular fibrillation was for this man the inevitable consequence of his underlying coronary artery disease. The doctors, in our respectful submission, should be asked to give evidence on that question and it's their medical opinion that we are looking for, not their understanding what might have been said in particular cases. If the Tribunal is content to proceed on that basis and if the doctors understand in effect what I have put, then that is the way we would ask the concurrent evidence to be taken. I think my friend endorses what I have just said. Counsel for the applicant indicated his endorsement of those remarks. 22 Counsel for the respondent then said: Yes, I agree, and, perhaps unnecessarily, I add that the real issue we say in this case is simply whether or not this man's ventricular fibrillation was the inevitable consequence of his underlying coronary artery disease. 23 The respondent's written outline of submissions referred to Comcare v Etheridge (2006) 149 FCR 522 and said of that case: 1.2 …It also indicates that the word "injury" is relevantly used in its ordinary English sense and that it is ultimately a question of fact whether the facts as found fall within that ordinary meaning. 24 Later in its written outline, the respondent said: 1.4 That second question is whether the putative "injury" is nonetheless the "inevitable" result of an underlying disease. If the answer to that question is positive, the event will not qualify as an "injury" in the requisite sense. The applicant does not dispute this principle, which she acknowledges (3.8 of her Statement of Facts, Issues and Contentions). It was accepted in Zickar v MGH Plastic Industries Pty Limited (1995) 187 CLR 310 at 318 and 325-327 per Brennan CJ, Dawson and Gaudron JJ, and was not contradicted in the majority joint judgement of Toohey, McHugh and Gummow JJ, whose statements at 326, 330-331, 333.8 and 334 would accommodate the proposition. Kirby J, the seventh judge in Zickar, agreeing with Toohey, McHugh and Gummow JJ as to result, made express, at 352, that the "approach to the definition of injury" which he favoured "does not necessarily mean that every catastrophe connected with a progressive disease will fall within the definition of 'personal injury', primarily so defined". Kirby J immediately proceeded to say that: "whether in the case of a progressive disease, leading inevitably to a sudden or identifiable pathological change, it can be said that such change constitutes a 'personal injury' can be left to determination on a case by case basis". 25 The respondent's submissions continued: 1.5 …[T]his second proposition (i.e. that the event relied on to comprise the "injury" cannot be the inevitable consequence of an underlying disease) has been acknowledged or accommodated in other cases, particularly Eduardo Ferro v Australian Postal Corporation [2010] AATA 119 at [48] and in Health Insurance Commission v Van Reesch & Anor [1996] FCA 1118; (1996) 45 ALD 302. 26 The respondent's statement of facts, issues and contentions had also referred to Zickar v MGH Plastic Industries Pty Ltd (1996) 187 CLR 310 ("Zickar"), Health Insurance Commission v Van Reesch [1996] FCA 1118; (1996) 45 ALD 302 ("Van Reesch") and Estate of Eduardo Ferro and Australian Postal Corporation [2010] AATA 119 ("Ferro") and relied upon them for the same or similar propositions. 27 The respondent's submissions concluded: 1.8 If … "the scene was set" for the Deceased, as the inevitable consequence of the underlying disease that he was suffering, that he would suffer ventricular fibrillation, and that is why he did suffer ventricular fibrillation, that ventricular fibrillation is not an "injury" in the requisite sense. 28 In his oral address, counsel for the applicant said: Really the way that the cases have developed is that it comes down to a distinction as between whether this ventricular fibrillation was really just the next part of the inevitable progress of the disease so it just can't be described as an injury, or whether it is a distinct event, whether or not - or even if caused by the disease, a distinct event that was not inevitable, not the inevitable result of the disease. If it's that, then it can properly be called an injury. 29 Counsel for the applicant submitted that as Professor O'Rourke had agreed that a person who has coronary artery disease may not necessarily experience ventricular fibrillation and may instead suffer myocardial infarction, it had not been demonstrated that the ventricular fibrillation was the inevitable result of the coronary artery disease. He also submitted that ventricular fibrillation was not "inevitable" because it might not necessarily have occurred on that day or at that level of severity. 30 Senior counsel for the respondent submitted: If the underlying disease inevitably leads to the ventricular fibrillation in the particular case, well, then that's what's happened as a matter of fact. Then it is not an injury. 31 Senior counsel for the respondent continued: In paragraph 11 of my friend's submissions, he does say that the only live issue is whether the ventricular fibrillation is the sole inevitable cause of the ravages of the disease. We accept that.

The Tribunal's decision 32 The Tribunal found against the applicant. In its reasons, under the heading "The question we must answer", the Tribunal said: 2. …The outcome of the proceedings turns on whether the ventricular fibrillation that occurred at work on 7 February 2012 can be regarded as an injury within the meaning of s 5A of the Act - in particular, whether it is an injury within the meaning of s 5A(1)(b), which refers to: …an injury (other than a disease) suffered by an employee, that is a physical or mental injury arising out of, or in the course of, the employee's employment… 3. There was no dispute that ventricular fibrillation meets one of the requirements the courts have said are inherent in the definition in s 5A(1)(b) - namely, that the employee suffered something in the nature of "a disturbance of the normal physiological state": Australian Postal Corporation v Burch (1998) 85 FCR 264 at 269 per Heerey, Sundberg and North JJ. But there is a second question that must be asked, and which will determine the outcome of these proceedings: was the ventricular fibrillation that Mr [Szajna] experienced on 7 February 2012 an inevitable consequence of his underlying coronary artery condition? If the answer is "yes", Mr [Szajna] did not suffer from an injury as that term is defined in s 5A of the Act. In substance, that means Mr [Szajna's] condition is wholly attributable to his underlying condition rather than anything occurring in his workplace, which means his employer is not liable to compensation to Mrs [Szajna] for her husband's untimely death. If ventricular fibrillation was not inevitable, the applicant will succeed. (Underlining added.) 33 The Tribunal then considered the medical evidence and accepted Professor O'Rourke's explanation that Mr Szajna's coronary artery disease compromised the heart so that at some indeterminate point the heart muscle must malfunction and ventricular fibrillation must occur. It accepted Professor O'Rourke's evidence that even if it had not occurred on 7 February 2012, it was inevitable that Mr Szajna would have experienced ventricular fibrillation at some point, provided he did not first die from another cause. 34 The Tribunal then concluded: 13. The law requires that we answer a precise question that may strike a lay observer (and the medical experts, for that matter) as counter-intuitive. We accept this may be one of those cases where it is difficult to follow how one fits medical evidence within legal rules. But that is what we must endeavour to do. Having asked and answered the question put to us, we must affirm the decision under review.

The grounds of appeal 35 The applicant's notice of appeal identifies the following questions as questions of law arising in the appeal: 1. Was it open to the Tribunal to conclude, on the facts as found by the Tribunal, that the ventricular fibrillation suffered by the Deceased was not an "injury" within the meaning of s 5A(1) of the SRC Act? 2. Did the Tribunal misconstrue the term "injury" as it appears in s 5A(1) of the SRC Act by imposing a test of whether the ventricular fibrillation suffered by the Deceased was wholly attributable to his underlying coronary artery condition? 3. Did the Tribunal misconstrue the term "injury" as it appears in s 5A(1) of the SRC Act by excluding the ventricular fibrillation suffered by the Deceased from the concept of "injury" on the basis that [the] Deceased would have experienced ventricular fibrillation at some point in the future in the absence of other events? 36 The applicant's case, as argued, focussed on the third of these "questions of law". 37 The grounds relied on by the applicant are: 1. On the facts as found by the Tribunal, it was not open to the Tribunal to conclude that the ventricular fibrillation suffered by the Deceased was not an "injury" within the meaning of s 5A(1) of the SRC Act in circumstances where it found that: (a) The Deceased suffered from a coronary artery condition. (b) The coronary artery condition caused the Deceased to suffer an episode of ventricular fibrillation. (c) The ventricular fibrillation was a disturbance of the normal physiological state. (d) Many people who experience untreated coronary artery disease will not develop ventricular fibrillation over the course of their lives. (e) It was not inevitable that the Deceased would experience ventricular fibrillation on a particular date. (f) It was inevitable the Deceased would experience ventricular fibrillation at some point in the future in the absence of other events. (g) At some indeterminate point in the future, the Deceased's heart muscle must malfunction and ventricular fibrillation would occur. 2. The Tribunal misconstrued the term "injury" as it appears in s 5A(1) of the SRC Act by posing and answering the wrong question, namely whether the ventricular fibrillation suffered by the Deceased was wholly attributable to his underlying condition rather than anything occurring in his workplace. 3. The Tribunal misconstrued the term "injury" as it appears in s 5A(1) of the SRC Act in that it wrongly excluded the ventricular fibrillation suffered by the Deceased from the concept of "injury" on the basis that, if not for the event on 7 February 2012, the Deceased would have experienced ventricular fibrillation at some point in the future in the absence of the other events. 38 The respondent filed a notice of objection to the competency of the appeal on the basis that the notice of appeal is not limited to questions of law as required by s 44 of AAT Act.

The submissions 39 The applicant submits that: (a) the Tribunal had mistakenly read into the expression "injury" in s 5A(1)(b) of the SRC Act a requirement that is not there, namely that the relevant physiological change or disturbance of the normal physiological state not be an inevitable progression of an underlying disease; (b) the error appears to derive from reading too much into a mere factual observation in Zickar at 334; and (c) once the Tribunal found that there had been a sudden and ascertainable or dramatic physiological change or disturbance of the normal physiological state, the Tribunal was required to find that the applicant had sustained an injury. 40 The respondent submits that: (a) the real point of contention before the Tribunal was whether Professor O'Rourke was correct in his opinion that ventricular fibrillation was the inevitable consequence of the progression of Mr Szajna's coronary artery disease; (b) the issue of inevitability was posed by the parties, and answered by the Tribunal, as a question of fact, not law; (c) the question of whether there was an "injury" is itself a question of fact, not law; (d) the Tribunal was entitled to find, as a matter of fact, that the inevitable result of an underlying disease did not fall within the word "injury"; and (e) as the applicant cannot demonstrate an error of law, the appeal cannot succeed.

Consideration 41 The Tribunal's function was to decide whether the decision made by the respondent to affirm its determination that the applicant was not entitled to compensation was the correct decision: Shi v Migration Agents Registration Authority (2008) 235 CLR 286 at [140] per Kiefel J. The only contentious issue before the Tribunal was whether Mr Szajna had suffered an "injury" within the meaning of that term in ss 5A(1) and 14(1) of the SRC Act. The approach of both parties was that this issue would be determined solely by the Tribunal answering the question of whether the ventricular fibrillation experienced by Mr Szajna on 7 February 2012 was the inevitable consequence of his underlying coronary artery disease. The parties concurred that if the answer was "yes", Mr Szajna had not suffered an "injury" within ss 5A(1) and 14(1) and the applicant was not entitled to compensation. 42 The Tribunal did what it was asked to do by the parties. It decided the question that they posed. Having decided that question, it concluded that there was no "injury" within ss 5A(1) and 14(1), as the parties agreed it must, and affirmed the decision under review. 43 The applicant now submits that having concluded that Mr Szajna's ventricular fibrillation was an inevitable consequence of his underlying coronary artery disease, the Tribunal made an error of law by concluding that it was then required as a matter of law to decide that Mr Szajna had not suffered an "injury". The substance of the applicant's argument is that the Tribunal applied a principle of law that does not exist. The purported principle is that a sudden physiological change that is an inevitable consequence of an underlying disease cannot be an "injury" within s 5A(1)(b) of the SRC Act. The applicant's argument is a deeply unattractive one because she relies upon an alleged error that she accepts the parties induced the Tribunal to make. 44 As unattractive as that argument may be, a decision of a Tribunal which is wrong in law, even though the error was substantially contributed to by the party bringing the appeal, may be overturned. The conduct of the applicant's case before the Tribunal goes to the Court's discretion as to whether to grant relief, rather than the question of whether an error of law was made: Kuswardana v Minister for Immigration & Ethnic Affairs (1981) 35 ALR 186 at 195; Hospital Benefit Fund of Western Australia Inc v Minister for Health, Housing and Community Services (1992) 39 FCR 225 at 231-233. 45 However, the respondent has not advanced any submission that relief should be refused on discretionary grounds. Rather, its case is that the Tribunal's decision involved only questions of fact and that nothing that can be characterised as an error of law has been alleged against the Tribunal or was made by the Tribunal. 46 In my opinion, the disposition of this appeal requires consideration of three issues: (a) Does the law preclude a sudden disturbance of a person's physiological state from being an "injury" if that disturbance is an inevitable consequence of an underlying disease? (b) Did the Tribunal consider that it was required as a matter of law to decide that Mr Szajna had not suffered an "injury" within the ordinary meaning of that word upon finding that the disturbance was an inevitable result of the underlying disease? (c) Did the Tribunal make an error of law?

The first issue: Does the law preclude a sudden disturbance of a person's physiological state from being an "injury" if that disturbance is an inevitable consequence of an underlying disease? 47 There was no dispute between the parties that Mr Szajna was an employee of the respondent, that he had suffered ventricular fibrillation in the course of his employment and that the ventricular fibrillation had resulted in his death. The dispute was confined to whether he had suffered an injury within the meaning of that word in ss 5A(1) and 14(1) of the SRC Act. 48 As the definition of "injury" in s 5A(1) of the SRC Act is pivotal to this appeal, it is worth repeating. Under that provision: "injury" means: (a) a disease suffered by an employee; or (b) an injury (other than a disease) suffered by an employee, that is a physical or mental injury arising out of, or in the course of, the employee's employment. 49 The applicant contended before the Tribunal that Mr Szajna suffered "an injury (other than a disease)", within paragraph (b) of s 5A(1), namely ventricular fibrillation. She did not argue that Mr Szajna had suffered a "disease" within paragraph (a). 50 The applicant proceeded in this way because the definition of "disease" in s 5B(1) of the SRC Act requires that there be a contribution to the ailment to a significant degree by the employee's employment. There was no evidence that Mr Szajna's employment with the respondent made any contribution to his coronary artery disease or to the consequent ventricular fibrillation that led to his death. 51 The words "in the course of, the employee's employment" in paragraph (b) of s 5A(1) (as an alternative to "arising out of") have the effect that no causal link is required between the "injury (other than a disease)" and the employment. It is enough that an "injury (other than a disease)" is sustained by an employee while performing his or her duties or doing something that he or she is reasonably required, expected or authorised to do in order to carry out such duties: Henderson v Commissioner of Railways (WA) (1937) 58 CLR 281 at 293-294 per Dixon J. 52 Accordingly, the issue for the Tribunal was whether the ventricular fibrillation suffered by Mr Szajna was an "injury (other than a disease)". In that expression, the word "disease" bears the meaning that it is given under s 5B(1): Australian Postal Corporation v Burch (1988) 85 FCR 264 at 268 ("Burch"). As there was no suggestion that Mr Szajna's ventricular fibrillation was a "disease" as defined in s 5B(1), the issue for the Tribunal devolved to whether the ventricular fibrillation was an "injury" under the ordinary meaning of that word. 53 The ordinary meaning of "injury" in workers' compensation legislation is "a sudden or identifiable physiological change": see Kennedy Cleaning Services Limited v Petkoska (2000) 200 CLR 286 ("Petkoska") per Gleeson CJ and Kirby J at [35]; Zickar at 336 per Kirby J. It is something distinct from the defect, disorder or morbid condition which enables it to occur: Accident Compensation Commission v McIntosh [1991] 2 VR 253 ("Accident Compensation Commission v McIntosh") per Murphy J at 262; Zickar at 335 per Toohey, McHugh and Gummow JJ; Petkoska at [36], [39] per Gleeson CJ and Kirby J. The issue arising here is whether the law qualifies the meaning of "injury" by providing that it does not encompass the inevitable consequence of an underlying disease. 54 Some of the submissions to the Tribunal concerning the significance of whether Mr Szajna's ventricular fibrillation was an inevitable consequence of his underlying coronary artery disease cited Ferro as their source. In Ferro, an employee had underlying coronary artery disease which resulted in ventricular fibrillation while he was at work, causing permanent brain damage. In that case, the Tribunal stated that: 45. The respondent contended that Mr Ferro's coronary occlusion and the ventricular fibrillation were inevitable. In Zickar v MGH Plastic Industries Pty Limited (1996) 187 CLR 310 (Zickar) the principle enunciated by the minority, and implicitly acknowledged by the majority, was that the inevitable consequences of the progress of a disease are not considered to be an injury simpliciter. 55 The Tribunal in Ferro went on to consider Burch and Petkoska and stated that: 48. Neither Burch nor [Petkoska] have challenged the clear recognition in Zickar that inevitable consequences, such as the progress of a disease, are not considered an injury simpliciter. 56 In Ferro, the Tribunal considered that the decision in Zickar established a "principle" that an inevitable consequence of a disease cannot amount to an "injury". It is necessary to examine Zickar to see whether it did establish such a principle. It will then be necessary to consider whether the Tribunal in this case purported to apply any such principle. 57 In Zickar, an employee suffered a ruptured aneurysm while he was at work, which caused an intracerebral clot and occlusion of a cerebral artery, resulting in brain damage. The evidence of Dr Stening, a neurosurgeon, was that an aneurysm is an area of weakness in the wall of a blood vessel supplying the brain. The weakness in the blood vessel wall balloons out and becomes thinner and thinner until the pressure of the blood behind it causes a tear, resulting in a leakage of blood into the fluid surrounding the brain. The blood's clotting mechanism may stop the bleed from progressing, but eventually the clotting mechanism breaks down causing a major rupture which is usually fatal. This is what had apparently happened to the employee in that case. 58 The structure and content of legislative provision considered by the High Court in Zickar was similar to s 5A(1) of the SRC Act. That provision defined "injury" to mean, relevantly, "personal injury" in paragraph (a) and "disease" in paragraph (b). The issue for the High Court was whether the definition of "injury" should be construed to mean that the natural consequences of a disease could be a "personal injury" within paragraph (a), or whether such consequences were only capable of coming within "disease" in paragraph (b). It is relevant to note that the case involved not merely the construction of "personal injury" but also the construction of the whole of the defined term "injury". 59 The minority judgment was given by Brennan CJ and Dawson and Gaudron JJ. Their Honours followed a long line of High Court authority which held that an identifiable physiological change resulting from the natural progression of a disease was not "injury by accident" or "injury" within the ordinary meaning of those terms in the relevant statutes. Their Honours referred, for example, to The Commonwealth v Ockenden (1958) 99 CLR 215, where Dixon CJ and Fullagar and Taylor JJ said at 224: Accordingly, for the purposes of the Commonwealth Employees' Compensation Act it is still true that a worker does not suffer personal injury by accident arising in the course of his employment where he suffers, at his place of employment, a sudden and distinct physiological change as the product of the inevitable development of a progressive disease from which he is suffering and where such change can in no way be attributable to or associated with some incident of his employment. 60 In construing the meaning of "injury", Brennan CJ and Dawson and Gaudron JJ applied Hockey v Yelland (1984) 157 CLR 124 which held that if an autogenous disease naturally progresses until it results in incapacity there is no "injury". The minority held that the essential steps and reasoning in Hockey v Yelland were established by a consistent and unbroken line of authority and concluded that the sole consequence of a progressive autogenous disease is not an "injury". 61 Therefore, the Tribunal in Ferro was correct that the minority in Zickar took the view that the inevitable consequences of the progression of a disease are not considered to be an "injury simpliciter" within paragraph (a) of the definition of "injury" considered in Zickar. That definition is not relevantly distinguishable from the definition of "injury" in s 5A(1) of the SRC Act. However, the minority's view cannot be considered to establish a "principle" unless it is consistent with the position adopted by the majority. That remains to be examined. 62 The majority consisted of Toohey, McHugh and Gummow JJ, who delivered a joint judgment, and Kirby J who delivered a separate judgment. In the joint judgment, their Honours explained that Hockey v Yelland must be read in its confined context of deciding whether the decision of the Tribunal in question demonstrated any error on the face of the record. Their Honours said at 333: If nothing more appeared than that the haemorrhage was merely the culmination or climax of a progressive disease, it could not be said that the rejection of the claim by reference to the opening words of the definition disclosed an error on the face of the record. But that is not the present case. 63 Their Honours continued at 334: But the present case is not one of an autogenous disease. Or, to put it more accurately, it is not an autogenous disease upon which the appellant relies. It may be accepted that the aneurism was an autogenous disease but the appellant's claim to personal injury within par (a) was based on the rupture which occurred. From Dr Stening's evidence, it is clear that the rupture of the aneurism was not inevitable and further that the rupture may have been minor, allowing the appellant, after treatment to return to his previous occupation. If there was no rupture there would be no event answering the description of personal injury and the appellant would be driven to rely upon par (b) of the definition. But there was such an event and the presence of a disease does not preclude reliance upon that event as personal injury. 64 Their Honours went on to say at 334-335: To say that the aneurism was a disease does not answer the question whether the rupture itself can fairly be described as an injury. Thus in Darling Island Stevedoring & Lighterage Co Ltd v Hankinson [(1967) 117 CLR 19] a worker suffered pain and later paralysis caused by the collapse of one or two infected vertebral bodies. The consensus of medical opinion was that the infection, unless discovered and treated successfully, would in the ordinary course of events have progressed ultimately to produce a collapse of the vertebrae and incapacity. The Workers' Compensation Commission treated the matter as an aggravation, acceleration, exacerbation and deterioration of a pre-existing disease. However, this Court held that the collapse of the vertebrae was an "injury" in the ordinary sense without resort to the extended definition in s 6(1)(b) of the Workers' Compensation Act 1926 (NSW). The decision is mentioned in Hockey v Yelland without any doubt being cast on its correctness. 65 I do not think that the judgment of Toohey, McHugh and Gummow JJ in Zickar supports any "principle" that the inevitable consequences of a disease cannot be an "injury" within the ordinary meaning of that word. Their Honours' citation of Darling Island Stevedoring & Lighterage Co Ltd v Hankinson (1967) 117 CLR 19, a case dealing with the consequence of a disease that was inevitable in the ordinary course of events, is inconsistent with any such principle. No support for such a principle can be inferred from their Honours' reference to Dr Stening's evidence that the rupture of the aneurysm was not inevitable. Their Honours were saying only that any evidence that the rupture was inevitable would have been relevant to the question of whether there was an "injury". Their Honours indicated that other factors affected that question, including whether the consequences of the rupture would have been less severe than from the mere progression of the disease, and whether the consequences could have been ameliorated by treatment. I consider that their Honours were saying no more than that the question of whether the consequences of a progressive disease amount to an "injury" depends on the evidence, and that whether such consequences are inevitable is a factor to be considered. Their Honours decided that as a matter of construction of the definition of "injury", a rupture which is a consequence of an underlying disease is not necessarily excluded as a "personal injury" within paragraph (a). 66 Kirby J's judgment is to similar effect. His Honour considered that Hockey v Yelland should be overruled and then said at 352: The approach to the definition of "injury" which I have favoured does not necessarily mean that every catastrophe connected with a progressive disease will fall within the definition of "personal injury" primarily so defined. Whether, in the case of a progressive disease, leading inevitably to a sudden or identifiable pathological change, it can be said that such change constitutes a "personal injury" can be left to determination on a case by case basis. It must be assumed that parliament intended the extended definition, enacted to cover cases of "disease" within s 4B of the 1987 Act, to have some operation. 67 In Burch, the employee had cardiomyopathy and apparently suffered an occlusion, or blocking, of a cerebral artery which caused a stroke. The claim for compensation was brought under the SRC Act. The Full Court considered that the stroke, which had been caused by the occlusion of an artery, could amount to an "injury". The Court cited the following passage from Accident Compensation Commission v McIntosh at 263, which, in my view, is far from supporting any principle to the effect suggested in Ferro: Long before the inclusion of these references to "disease" in the definition of "injury" [in the New South Wales legislation considered in O'Neill v Lumbey (1987) 11 NSWLR 640], claims for coronary occlusions, cerebral haemorrhage, ruptured aneurysms, aorta, oesophagus etc had commonly been made and had succeeded if occurring during a protected period, on the basis that they were "injury by accident", being clearly a physical injury - and accidental - being unexpected by the worker at the time that they occurred: cf. Clover, Clayton & Co. Ltd. v Hughes [1910] AC 242. 68 In Petkoska, an employee had been suffering from a condition of the heart which led to fibrillation and the release of a clot into the blood stream which then caused a stroke. A magistrate found that the employee had sustained a "physical injury" even though the stroke was probably initiated by heart disease. The employer argued that the legislation considered there was distinguishable from that considered in Zickar and that the stroke, being a consequence of a disease, was not an "injury". 69 McHugh, Gummow and Hayne JJ gave a joint judgment in which they concluded that the legislation under consideration was even more strongly in favour of the worker than in Zickar. In the course of their judgment, their Honours said: 68 The circumstance that a sudden physiological change has been caused or provoked by disease does not prevent it from constituting a "physical injury" for the purposes of s 7(1). 70 Gaudron J gave a separate judgment agreeing with McHugh, Gummow and Hayne JJ, but added some observations. Her Honour said: 50 Whether physiological change resulting from a progressive disease that is not employment related is or is not an injury for the purposes of workers' compensation legislation depends on the terms of the legislation in question. There is no doubt that, as a matter of ordinary language, the word "injury" is apt to include sudden physiological change resulting from a disease, as in the case of stroke resulting from progressive heart disease or the rupture of an aneurysm as a result of the progressive weakening of an arterial wall. 71 Gleeson CJ and Kirby J agreed that the appeal should be dismissed. Their joint reasons analysed the decision in Zickar, concluding at [39]-[40]: It is impossible to reconcile the approach urged by the appellant in this case with the reasoning of the majority in Zickar. If the appellant's approach were adopted, the mere fact that an ascertainable lesion or dramatic physiological change had taken place or that the normal physiological state had been disturbed would be irrelevant because it would be no more than the outcome, direct or indirect, of a progressive congenital or other disease process. However, this is not the way the majority approached the matter in Zickar. It is also inconsistent with the approach in McIntosh and Burch. All of those cases require that consideration be given to the precise evidence, on a fact by fact basis, concerning the nature and incidents of the physiological change accepted at trial. If this evidence amounts, relevantly, to something that can be described as a sudden and ascertainable or dramatic physiological change or disturbance of the normal physiological state, it may qualify for characterisation as an "injury" in the primary sense of that word. If such an injury happens within the protected period of employment, it is ordinarily compensable without proof of a specific causal connection with the worker's employment. If the propounded "injury" is distinct from the underlying pathology that constitutes a "disease" that directly or indirectly caused the sudden event to occur, it is unnecessary to proceed to the alternative and additional basis whereby, in such cases, compensation may also be recovered for the disease process if the statutory preconditions are met. The foregoing approach does not rob the disease provisions of the Act of utility. They would apply in cases of a disease in the nature of dermatitis, lead poisoning, brucellosis and many others of a progressive type. The disease provisions remain as alternative and additional heads of entitlement where a disease pathology exists with the appropriate employment connection, and does not manifest itself in the kind of sudden physiological change or disturbance of the normal physiological state that will constitute an "injury" in the primary sense. (Underlining added.) 72 Callinan J dissented in Petkoska. His Honour considered that the decision in Hockey v Yelland should be followed. 73 There is no suggestion in the judgments of the majority in Petkoska that an inevitable consequence of a disease cannot be an "injury" within the ordinary meaning of that word. In fact, the passages I have cited suggest the contrary. 74 The respondent's submissions to the Tribunal suggest that the decision of the Full Court of the Federal Court in Van Reesch supports the position that the inevitable consequence of disease cannot be an "injury". However, that is not so. 75 Another difficulty with the idea that there is a principle that the inevitable consequence of an underlying disease cannot amount to an "injury" within the ordinary meaning of that word lies in understanding what is meant by "inevitable". No doubt, there are many diseases of which it can be said that without treatment they will inevitably progress such that in the long term they will produce some sudden identifiable physiological change which is distinct from the disease. Some examples may be, depending on the evidence in a particular case, coronary occlusions, cerebral haemorrhages and ruptured aneurysms resulting in stroke. If, in fact, a person experiences such consequences in the short term, it is difficult to see why it must necessarily follow that the person has not suffered an "injury" in the ordinary sense of that word. The person has, after all, now experienced a sudden identifiable physiological change distinct from the disease that resulted in such change, regardless of the fact that such change would inevitably have been experienced in the long term. 76 What the cases establish is that: (a) In order to decide whether an employee has sustained an "injury" within the ordinary meaning of that word, consideration must be given to the precise evidence on a case by case basis. (b) If the evidence establishes something that can be described as a sudden and ascertainable or dramatic physiological change or disturbance of the normal physiological state, it may qualify as such an "injury". (c) It is necessary to consider whether the propounded "injury" is distinct from the underlying pathology that constitutes a "disease" that directly or indirectly caused the sudden change to occur. (d) The question of whether the physiological change or disturbance is the inevitable consequence of the progress of the disease may be relevant in deciding whether there is an "injury", but is not of itself necessarily determinative. 77 I consider that neither the decision of the majority in Zickar nor any other case since then establishes or supports any principle that the inevitable consequences of the progress of the disease cannot be an "injury". While such a principle is consistent with the view taken by Brennan CJ and Dawson and Gaudron JJ in Zickar and by Callinan J in Petkoska, theirs were dissenting opinions. 78 The references in the judgments of the majority in Zickar to "inevitability" are no more than an indication that there may be some circumstances in which it may be appropriate for a tribunal of fact to conclude that sudden manifestations of the inevitable consequences of an underlying disease may themselves be regarded as part of the disease, rather than an "injury". Gleeson CJ and Kirby J in Petkoska at [40] suggest that such circumstances may be unusual. I consider that that Ferro is incorrect insofar as it decided that a principle exists that the inevitable consequences of a disease cannot be an "injury" within the ordinary meaning of that word.

The second issue: Did the Tribunal consider that it was bound as a matter of law to decide that Mr Szajna had not suffered an "injury" within the ordinary meaning of that word upon finding that the disturbance was an inevitable result of the underlying disease? 79 It is necessary to consider whether the Tribunal purported to apply a "principle" that the inevitable consequences of the progress of a disease cannot be considered to be an "injury" within the ordinary meaning of that word. The respondent submits that the question of whether Mr Szajna had suffered an "injury" within s 5A(1) was presented by the parties to the Tribunal as a question of fact and must therefore have been decided by the Tribunal as a question of fact. It points out that the Tribunal did not did not state that it applied Ferro or refer to that case. 80 The parties presented the question of whether Mr Szajna's ventricular fibrillation was the inevitable consequence of his underlying coronary artery disease solely as a question of fact. However, the parties' submissions as to the consequences of that finding were sometimes presented as a question of law, sometimes as a question of fact and sometimes indeterminately. For example, in the passages set out at [19], [21], [22], [23], [27] and [30] of these reasons, it seems to have been submitted that whether there was an "injury" was a question of fact. However, in the passages described at [17], [24], [25] and [28], the submissions were to the effect that the inevitable consequences of a disease are not, as a matter of law, to be regarded as an "injury" within its ordinary meaning. The submissions of both parties referred to and encouraged the Tribunal to apply the decision in Ferro. Accordingly, I do not accept the respondent's submission that the Tribunal could not have applied the "principle" described in Ferro and I do not accept that the Tribunal must necessarily have regarded the question of "injury" as a question of fact, not law. 81 In its reasons, the Tribunal described the question which it said would determine the outcome of the application and the consequence of the answer as follows: [W]as the ventricular fibrillation that Mr [Szajna] experienced on 7 February 2012 an inevitable consequence of his underlying coronary artery condition? If the answer is "yes", Mr [Szajna] did not suffer from an injury as that term was defined in s 5A of the Act. (Underlining added.) 82 The Tribunal stated that the answer "yes" to the question of fact posed would mean that there was no "injury as that term is defined in s 5A". It did not consider merely that the answer "yes" to the question of fact would mean that there was no "injury" within the ordinary meaning of that word. As I will explain later, the distinction has some significance. 83 The Tribunal went on to explain why it considered that the answer "yes" would mean that Mr Szajna did not suffer from an "injury". It said: In substance, that means Mr [Szajna's] condition is wholly attributable to his underlying condition rather than anything occurring in his workplace… 84 It is not entirely clear what the Tribunal meant in this passage. The Tribunal seems to have thought that the fact that the physiological change relied upon by the applicant was an inevitable consequence of an underlying disease must have the consequence that the physiological change is not attributable, or causally connected, to the workplace and that such a causal connection is required. That is consistent with the Tribunal taking the approach the parties urged it to take that the inevitable consequences of the progress of a disease is to be regarded as merely part of the disease and cannot be an "injury" within s 5A(1) in the absence of a causal connection with the employment. 85 That the Tribunal took such an approach is also consistent with its conclusion that: The law requires that we answer a precise question that may strike a lay observer (and the medical experts, for that matter) as counter-intuitive. We accept this may be one of those cases where it is difficult to follow how one fits medical evidence within legal rules. But that is what we must endeavour to do. Having asked and answered the question put to us, we must affirm the decision under review. 86 The question that the Tribunal referred to was whether the ventricular fibrillation, being a sudden physiological disturbance, was an inevitable consequence of Mr Szajna's coronary artery disease. The Tribunal's references to requirements of "the law" and to "legal rules" indicate that it regarded itself as being bound as a matter of law to conclude that Mr Szajna had not suffered an "injury" as that term is defined in s 5A(1) of the SRC Act upon finding that the ventricular fibrillation was such an inevitable consequence. The parties had urged the Tribunal to apply Ferro, and it is probable that the Tribunal did apply the "principle" described in that case.

The third issue: Did the Tribunal make an error of law? 87 The respondent submits that whether Mr Szajna had suffered an "injury" within s 5A(1) was question of fact, that any error committed by the Tribunal in construing the word "injury" could only have been an error of fact, not law, and that, accordingly, s 44(1) is not engaged. 88 The respondent relied on Comcare v Etheridge. In that case one of the purported questions of law was whether "the inhalation or ingestion of an asbestos fibre is to be characterised as a matter of law as an injury (other than a disease) within the definition of 'injury' contained in s 4(1) of the SRC Act." Section 4(1) was in terms almost identical to the present s 5A(1). Branson J (with whom Spender and Nicholson JJ agreed) stated: 25 …[T]he question of whether a particular employee suffered an injury (other than a disease) within the meaning of s 4(1) of the SRC Act cannot be determined merely by reference to the terms of that Act and previously decided cases. On any claim made under the SRC Act in which the issue of whether the relevant employee suffered an injury (other than a disease) within the meaning of the Act is contested, determination of that issue will depend in part upon the proper construction of the definition of "injury" contained in s 4(1) and in part upon the evidence or admissions relied upon in support of the claim. In the absence of relevant admissions, the necessary evidence will have two aspects; first, evidence that the employee suffered something, and second, evidence that the something which he or she suffered was an "injury" within the meaning of the definition. 26 It is not suggested that the word "injury" is used in s 4(1) in other than its ordinary or common meaning. Consequently, and notwithstanding the potential relevance of expert evidence … the question of whether facts as found fall within the meaning of the word "injury" as defined is a question of fact rather than a question of law (Hope v Bathurst City Council (1980) 144 CLR 1 per Mason J at 7). 27 This is not to say that a finding by the Tribunal that a particular condition of the body is or is not to be characterised as an injury (other than a disease) within the relevant definition is not subject to judicial review. If the Tribunal reaches its finding by, eg, taking into account irrelevant information, by failing to take into account a relevant consideration or because it misapprehends what the term "injury" connotes in the SRC Act, its decision will be amenable to an order of review under s 5 of the ADJR Act. 89 Branson J's indication in [26] that the word "injury" is used in its ordinary or common meaning raises the question of which use of "injury" in s 4(1) of the SRC Act her Honour was referring to. The word "injury" appeared six times in s 4(1) of the SRC Act (as it does in the present s 5A(1)). The first two are relevant. First, it is used in the opening words, "injury means". The word "injury" appearing in that phrase is then defined in terms of paragraphs (a), (b) and (c). Next, it is used in paragraph (b) in the phrase "injury (other than a disease)". 90 Read in context, Branson J indicated that the word "injury" in the phrase "injury (other than a disease)" has its ordinary meaning, and the question of whether facts as found fall within that ordinary meaning of is not a question of law for the purposes of s 44(1) of the AAT Act. However, her Honour did not suggest that the word "injury" in the phrase "injury means" has its ordinary meaning. That word is defined and given a meaning that in part extends and in part limits its ordinary meaning. The defined term "injury" is a technical legal term, and its meaning is a question of law: Collector of Customs v Agfa-Gevaert Ltd (1996) 186 CLR 389 at 397 ("Agfa-Gevaert"). 91 The applicant submits that Branson J held at [27] that the Tribunal would commit an appealable error of law if it misapprehends what the term "injury" connotes in the SRC Act. I consider that her Honour was there referring to misapprehension of the word "injury" in its ordinary meaning and indicating that some errors of mixed law and fact may be reviewable under the Administrative Decisions (Judicial Review) Act 1977 (Cth), but cannot be the subject of an appeal under s 44(1) of the AAT Act. The view that errors of mixed fact and law cannot be appealed has since been doubted, but that issue is not relevant to this case: see Comcare v Martinez (No 2) v Comcare (2013) 212 FCR 272 at [86]-[87] per Robertson J and O'Kane v Comcare [2014] FCA 341 at [81] per Robertson J. 92 The applicant's third purported question of law asks whether "the Tribunal misconstrued the term "injury" as it appears in s 5A(1) of the SRC Act". The question is ambiguous as to which use of "injury" it refers to, but I consider that it covers both the question of whether the Tribunal misconstrued the defined term "injury" and the term "injury" in the phrase "injury (other than a disease)". This is a case where it is alleged that the Tribunal misconstrued the word "injury" in both its defined and ordinary meanings. 93 The question of fact for the Tribunal to decide was whether Mr Szajna's ventricular fibrillation was an "injury" within the expression "injury (other than a disease)" in s 5A(1). However, the Tribunal concluded that because it decided that the ventricular fibrillation was an inevitable consequence of the underlying coronary artery disease, the law required it to then decide that "Mr [Szajna] did not suffer from an injury as that term is defined in s 5A of the Act" (underlining added). It is probable that the Tribunal reached this conclusion by adopting the view that there is a "principle" established by Zickar that the inevitable consequences of the progress of a disease are not an "injury" within the ordinary meaning of that term and then reasoning that, in the absence of a causal connection with employment, there could be no "injury" as that term is defined in s 5A(1). In any event, by concluding that the defined term "injury" incorporated a legal principle that did not exist, the Tribunal made an error of law. 94 I consider that the Tribunal also made an error of law by misconstruing the word "injury" in the phrase "injury (other than a disease)" in paragraph (b) of s 5A(1). The Tribunal, by adopting the "principle" described above, wrongly construed "injury" in paragraph (b) as having a technical legal meaning, when, in fact, it bears only its ordinary meaning. The question whether a word or phrase in a statute is to be given its ordinary meaning or some technical or other meaning is a question of law: Agfa-Gevaert at 397. In Comcare v Etheridge, Branson J indicated at [25] that whether an employee has suffered an "injury" cannot be determined merely by reference to the decided cases. Yet that was what the Tribunal did here. It wrongly regarded itself as being bound by the decided cases to reach a particular conclusion on a question of fact, namely whether the applicant had an "injury (other than a disease)". 95 The first purported question of law identified by the applicant was whether it was open to the Tribunal to conclude, on the facts as found by the Tribunal, that the ventricular fibrillation was not an "injury" within the meaning of s 5A(1) of the SRC Act. I understand this question to raise an argument that was put as an alternative to the third question. The argument was that if there is a principle that an inevitable consequence of a disease cannot be an "injury", then the Tribunal erred in its understanding of what is meant by "inevitable". It is unnecessary to address this question in light of my conclusion that there is no such principle. 96 I do not understand the applicant to press the ground supporting the second question of law that she propounded. 97 I emphasise that I intend no criticism of the Tribunal. The Tribunal decided the case in the way that it was asked to by the parties. Unfortunately, the approach that the parties urged on the Tribunal was informed by their common misunderstanding of the law. The argument run by the applicant in this appeal is entirely inconsistent with the approach it took before the Tribunal. 98 However, the applicant has demonstrated error of law. The respondent did not submit that there are discretionary reasons why relief ought to be refused. I will therefore allow the appeal and order that the Tribunal's decision be set aside and that the Tribunal hear and decide the application again. 99 As I have made plain, this appeal has been a product of the way the case was conducted by both parties in the Tribunal. I consider that fairness as between the parties requires that there should be no order as to the costs of the appeal. I certify that the preceding ninety-nine (99) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justice Rangiah.