High Court of Australia Mason C.J. Gaudron and McHugh JJ. Byrnes v Repatriation Commission [1993] HCA 51 ORDER Appeal allowed with costs. Set aside the order of the Full Court of the Federal Court and in lieu thereof: (i) allow the appeal to that Court with costs; and (ii) remit the matter to the Administrative Appeals Tribunal for determination. Cur. adv. vult. The Court delivered the following written judgment:— Sept. 15 Mason C.J., Gaudron and McHugh JJ. The question in the appeal is whether the Administrative Appeals Tribunal, Veterans' Appeals Division ("the Tribunal") erred in law in holding that it was satisfied "beyond reasonable doubt, that there is no sufficient ground for determining that the [appellant's] cervical and thoracic spondylosis was war-caused" for the purposes of the Veterans' Entitlements Act 1986 Cth ("the Act"). Between 7 September 1942 and 21 September 1945, the appellant served in the Royal Australian Navy ("R.A.N."). He claims that he suffered injury to his neck on three occasions during the course of that service. These injuries are the basis of his claim that his present condition of cervical and thoracic spondylosis is causally connected with his war service. He alleges that the first injury occurred at Townsville in February 1943 while he was on day leave from his R.A.N. unit. He ricked his neck when he dived into a swimming pool "where there was an insufficiency of water". According to the appellant he spent four or five days in Townsville General Hospital with "pretty severe" neck pain. He was treated with liniments and other medication to relieve the pain. After he rejoined his unit, the pain in his neck persisted for some weeks, particularly when he was working in confined spaces. He alleges that his neck was again injured some time after April 1943 while he was trimming coal on a ship which rolled unexpectedly. On this occasion he was hit hard on the back of the head and neck by a piece of coal. As a result he suffered "terrible pain" at the back of his neck and across his shoulders. In 1945, he suffered another injury when he fell and hit his head and shoulders on the riveted bulkhead of a ship. This fall caused severe pain to his head and shoulders. No record of the second and third incidents appears on the service record of the appellant, but the Tribunal found that this was "not surprising". Furthermore, although his service record contradicted the appellant's evidence concerning the month and duration of his stay in Townsville General Hospital, it gave considerable support to the appellant's account of that incident. The service record shows that the appellant spent three days in Townsville Hospital in January 1943 with "cervical myositis". This suggests that the appellant was admitted to hospital because he was suffering from some inflammation of the muscles in the cervical region of his spine. The only finding made by the Tribunal concerning the Townsville incident was that it "led to nothing except pain-killers and an absence from duty of three days for observation". However, the Tribunal also said "that there is no evidence to show that any of the three occurrences upon which [the appellant] bases his case caused severe injury". Medical support for the appellant's case was given by Dr. Rowden, an orthopaedic surgeon, who said in evidence that he thought that "it would be very wrong to state categorically" that there was no relationship between the injury sustained in Townsville and the appellant's present condition. Dr. Rowden thought that a link between the occurrences during the appellant's war service and his cervical spondylosis was a reasonable hypothesis. He said that he believed that the appellant had sustained a significant injury to his neck at Townsville. Dr. Rowden's hypothesis assumed that the injury was "a ligamentous injury to the neck and perhaps an injury to the disc, but this is all hypothetical, of course". He acknowledged that "we do not know the extent of ligamentous injury that this man received in that initial neck injury". But he said that, if there is an increase in movement of the cervical spine caused by ligamentous laxity, early degenerative changes can occur. In this case, he believed that the injury had increased the strain on the appellant's neck which had been further increased by work as a stoker. A different view was expressed by Dr. Whitty, another orthopaedic surgeon, who said that the hypothesis put forward by Dr. Rowden was unlikely. Dr. Whitty assessed the odds against it as "20 to 1". He said that, from the description of the injuries, he did not think they "were likely to be severe enough" to have caused the appellant's spondylosis. Dr. Whitty thought that the absence of any significant treatment to the appellant in January 1943 also indicated that the injury he sustained during that month was not severe. He also said that, if the three incidents were related to the appellant's spondylosis, bony changes to the appellant's cervical spine should have been evident by 1981. However, X-rays had revealed no such changes. Furthermore, there was no evidence of any injury to the appellant's thoracic spine during his war service. Dr. Whitty concluded that the appellant's spondylosis was the result of advancing age. Two government medical officers had also concluded that no connexion existed between the appellant's war service and his spondylosis. In his reasons for judgment, Dr. A. P. Renouf, a Senior Member of the Tribunal, considered the medical evidence and said: The medical evidence is reduced to that of the two medical officers of the respondent, the two X-ray reports and the evidence of Dr. Whitty and Dr. Rowden. Of this remaining evidence, only that of Dr. Rowden favours the applicant. This is one of the reasons why I do not believe that the material before me raises a reasonable hypothesis connecting the applicant's spondylosis with the circumstances of his service. Other reasons include that there is no evidence to show that any of the three occurrences upon which [the appellant] bases his case caused severe injury (I regard the second two as trivial while the first led to nothing except pain-killers and an absence from duty of three days for observation) and that despite the existence of an anxiety state, [the appellant] did not complain of nor seek medical treatment for his spinal problems either upon discharge or for many years thereafter. All I can find in the circumstances is that there is no more than a possibility of a causal connection between the applicant's spondylosis and his service. Hence, a reasonable hypothesis of such a connection has not been raised. This being the case, I am satisfied, beyond reasonable doubt, that there is no sufficient ground for determining that the applicant's cervical and thoracic spondylosis was war-caused. Upon this material, the question arises whether the reasons of the Tribunal in rejecting the appellant's claim contain an error of law. The answer to that question depends upon the construction and meaning of s. 120 of the Act which relevantly provides: (1) Where a claim under Part II for a pension in respect of the incapacity from injury or disease of a veteran, or of the death of a veteran, relates to the operational service rendered by the veteran, the Commission shall determine that the injury was a war-caused injury, that the disease was a war-caused disease or that the death of the veteran was war-caused, as the case may be, unless it is satisfied, beyond reasonable doubt, that there is no sufficient ground for making that determination. (3) In applying subsection (1) or (2) in respect of the incapacity of a person from injury or disease, or in respect of the death of a person, related to service rendered by the person, the Commission shall be satisfied, beyond reasonable doubt, that there is no sufficient ground for determining: (a) that the injury was a war-caused injury or a defence-caused injury; (b) that the disease was a war-caused disease or a defence-caused disease; or (c) that the death was war-caused or defence-caused; as the case may be, if the Commission, after consideration of the whole of the material before it, is of the opinion that the material before it does not raise a reasonable hypothesis connecting the injury, disease or death with the circumstances of the particular service rendered by the person. (6) Nothing in the provisions of this section, or in any other provision of this Act, shall be taken to impose on: (a) a claimant or applicant for a pension or increased pension, or for an allowance or other benefit, under this Act; or (b) the Commonwealth, the Department or any other person in relation to such a claim or application; any onus of proving any matter that is, or might be, relevant to the determination of the claim or application. Mr. Emmett Q.C., who appeared for the respondent, conceded that the Tribunal had made one error of law in giving its reasons. He accepted that the Tribunal's reasoning was "flawed" when it said that the material did not raise "a reasonable hypothesis connecting the [appellant's] spondylosis with the circumstances of his service" because "only" the evidence of Dr. Rowden favoured the appellant. This concession was correctly made. In Bushell v Repatriation Commission [1] , Mason C.J., Deane and McHugh JJ. pointed out that, for the purpose of s. 120(3), it is not decisive that a medical opinion that supports a hypothesis "has little support in the medical profession or among scientists". Their Honours went on to say [2] : [T]he case must be rare where it can be said that a hypothesis, based on the raised facts, is unreasonable when it is put forward by a medical practitioner who is eminent in the relevant field of knowledge. Conflict with other medical opinions is not sufficient to reject a hypothesis as unreasonable. 1. (1992) 175 C.L.R. 408, at p. 414. 2. ibid., at pp. 414-415. However, Mr. Emmett submitted that the Tribunal had relied on other, independent reasons in rejecting the appellant's claim and that those reasons contained no error. He submitted that the Tribunal's finding that there was no evidence that any of the three occurrences had "caused severe injury" meant that the evidentiary material raised no fact or facts which supported Dr. Rowden's hypothesis. In Bushell [1] , Mason C.J., Deane and McHugh JJ. said: The material will raise a reasonable hypothesis within the meaning of s. 120(3) if the material points to some fact or facts ("the raised facts") which support the hypothesis and if the hypothesis can be regarded as reasonable if the raised facts are true. Mr. Emmett placed much reliance on this passage. He asserted that, without evidence that the appellant had sustained a severe injury to his neck, the material did not "point to facts which, if they are true, [would] support the hypothesis" put forward by Dr. Rowden. Accordingly, the Tribunal had correctly applied the principal judgment in Bushell when the Tribunal held that it was satisfied beyond reasonable doubt that there was no sufficient ground for determining that the appellant's spondylosis was war-caused. 1. (1992) 175 C.L.R. 408, at p. 414. The statement in Bushell that the material must point to some fact or facts which support the hypothesis means no more than that the material before the Commission must raise some fact or facts which give rise to the hypothesis. When that fact or those facts have been identified, the question for determination is whether the hypothesis is reasonable. In Bushell [3] , Mason C.J., Deane and McHugh JJ. said: [A] hypothesis cannot be reasonable if it is "contrary to proved scientific facts or to the known phenomena of nature [4] ". Nor can it be reasonable if it is "obviously fanciful, impossible, incredible or not tenable or too remote or too tenuous" [5] . In some cases, the hypothesis may assume the occurrence or existence of a "fact". That itself does not make the hypothesis unreasonable. So, in the present case, the appellant's hypothesis is not unreasonable simply because it assumes that the appellant sustained a severe injury when he dived into a swimming pool in Townsville, notwithstanding that the materials before the Commission did not reveal the extent of the injury which he then suffered. 1. (1992) 175 C.L.R., at p. 414. 2. Commissioner for Government Transport v Adamcik (1961), 106 C.L.R. 292, at p. 306. 3. East v Repatriation Commission (1987), 16 F.C.R. 517, at p. 532. Once a reasonable hypothesis is raised, the question for the Commission is then whether it is satisfied beyond reasonable doubt that there is no sufficient ground for making a determination that the injury was war-caused. The Commission will be so satisfied if it is satisfied beyond reasonable doubt that the factual foundation of the hypothesis has been disproved [6] , either by proof beyond reasonable doubt that a fact or fact relied upon to support the hypothesis is not true, or by proof beyond reasonable doubt of the truth of a further fact, inconsistent with the hypothesis [7] . 1. Bushell (1992), 175 C.L.R., at p. 416. 2. ibid., at p. 427, per Brennan J. The passages in the joint judgment in Bushell that indicate that once the "raised facts" raise a reasonable hypothesis that is the end of the matter unless the raised facts are disproved [8] should not be taken to suggest that proof beyond reasonable doubt of a further, inconsistent fact will not be sufficient, under s. 120(1), to preclude a finding by the Commission that the injury was war-caused. The remarks of the majority in Bushell were directed specifically to a situation where the raised facts giving rise to the hypothesis covered "the whole of the material" bearing on the hypothesis. They were not directed to a case where the veteran relies on part only of the material before the decision maker. Proof beyond reasonable doubt of a fact inconsistent with the reasonable hypothesis would, by implication, demonstrate that "the factual foundation upon which the hypothesis can operate does not exist" [9] . 1. ibid., at pp. 414, 415-416. 2. (1992) 175 C.L.R., at p. 416, per Mason C.J., Deane and McHugh JJ.; see also p. 427, per Brennan J. The position may be summarized as follows: (1) First, sub-s. (3) of s. 120 is applied: do all or some of the facts raised by the material before the Commission give rise to a reasonable hypothesis connecting the veteran's injury with war service? The hypothesis will not be reasonable if it is contrary to known scientific facts or is obviously fanciful or untenable. If the hypothesis is not reasonable, the claim fails. Proof of facts is not in issue at this point. (2) If a reasonable hypothesis is established, sub-s. (1) of s. 120 is applied. The claim will succeed unless: (a) one or more of the facts necessary to support the hypothesis are disproved beyond reasonable doubt; or (b) the truth of another fact in the material, which is inconsistent with the hypothesis, is proved beyond reasonable doubt, thus disproving, beyond reasonable doubt, the hypothesis. Contrary to the submission of Mr. Emmett, the appellant's claim was not dependent on proof that he had sustained a severe injury. The sustaining of a severe injury was part of the hypothesis upon which the appellant relied to support his case. He testified that he had dived into a pool and injured his neck, causing him to be hospitalized. This was the factual foundation for the hypothesis that the dive had caused a severe ligamentous injury to his neck and perhaps to a disc. Because of ligamentous laxity, movement of the cervical spine had increased. This had caused early degenerative changes which had resulted in the appellant's spondylosis. Furthermore, the strain on the appellant's neck had been further increased by his naval work as a stoker. If the appellant had been able to prove that he sustained a severe injury to his neck, part of the hypothesis would have been proved. Indeed, proof of a severe injury would have been the factual foundation of another hypothesis leading to the same conclusion but with a higher degree of probability than the hypothesis upon which the appellant was forced to rely. Similarly, proof beyond reasonable doubt that the appellant had not suffered a severe injury would have disproved the hypothesis put forward by Dr. Rowden. In the absence of proof that the appellant had or had not sustained a severe injury, however, his case had to be determined by examining whether it was a reasonable hypothesis that his spondylosis was caused by an injury to his neck which occurred when he dived into a shallow pool causing him to be hospitalized for three days. His case could succeed even though there was no evidence that the 1943 incident had resulted in severe injury. Sustaining severe injury was part of the hypothesis; it was not a matter for proof or evidence in his case. As a matter of law and not merely of fact, once a reasonable hypothesis was raised the Commission was bound to find in favour of the appellant unless it was satisfied beyond reasonable doubt of at least one of two matters. First, that the appellant had not suffered injury of such severity to set in train a process which could cause spondylosis. Secondly, that the evidence of Dr. Rowden concerning the hypothesis and the evidence of Dr. Whitty that there was a 20 to 1 chance of it being correct were unacceptable. Only if one or other of these matters were negatived to the required standard of proof would it be open to the Commission to conclude that the injury was not war-caused. Although nothing in s. 120 (see s. 120(6)) imposes on any person any onus of proving any matter relevant to a determination under that section, the Commission, as a matter of law, could not be "satisfied, beyond reasonable doubt, that there is no sufficient ground for making that determination" (s. 120(1)) unless it was satisfied as to one or other of these matters. Two specialists, eminent in their field, were agreed that diving into a pool and injuring the neck of the diver could lead to spondylosis of the neck. They disagreed merely as to the likelihood that the diving and neck injury in this case had led to spondylosis. Although Dr. Whitty thought that the hypothesis was unlikely, he nevertheless conceded that there was one chance in twenty-one that the hypothesis was valid. It was not open to the Tribunal, therefore, to say that the hypothesis relied on by the appellant was not reasonable because there was only a 20 to 1 chance of it being valid. A hypothesis within that degree of probability cannot as a matter of law be regarded as unreasonable for the purposes of s. 120. The Tribunal made no finding that it was satisfied beyond reasonable doubt that the appellant had not suffered a severe ligamentous injury to his neck. Nor was it open to the Tribunal to make such a finding. No material was put before the Tribunal which would entitle it to make such a finding. Dr. Whitty thought that the absence of any significant treatment to the appellant's neck in Townsville in 1943 indicated that the injury was not severe. But this evidence is not capable of proving beyond reasonable doubt that the appellant did not sustain a severe injury. Moreover, Dr. Whitty's concession that there was a 20 to 1 chance that the hypothesis of Dr. Rowden was correct confirms the existence of a reasonable doubt as to whether the appellant suffered a serious injury. Furthermore, the Tribunal made no finding that it rejected Dr. Whitty's evidence that there was a 20 to 1 chance that the hypothesis put forward by the appellant was correct. On the contrary, it seems to have acted upon his evidence. It follows that it was not open to the Tribunal to be satisfied that there was no sufficient ground for making the determination. Accordingly, the appeal must be allowed. Because the appellant has sought no more than an order that the matter be remitted to the Tribunal for determination according to law, it is unnecessary to determine whether it would be appropriate for this Court to determine the claim of the appellant.