Practice and Procedure - effect of a previous decision on the same matter by the Tribunal considered - question whether that decision gave rise to res judicata or issue estoppel - consideration of relevant statutory provisions.

Veterans' Entitlements Act 1986 ss.6, 8, 14, 120(1), 120(3), 175

Administrative Appeals Tribunal Act 1975 s.37

Re Repatriation Commission and Cruise Decision No. 5881, 8 May 1990

Re Cooper and Commonwealth of Australia (1988) 16 ALD 213

Re Hopper and Australian Meat and Livestock Research (1990) 11 AAR 329

Re Bertram and Repatriation Commission Decision No. 7188, 11 June 1991

Re Langley and Repatriation Commission [1992] AATA 73; (1992) 15 AAR 417

Re Plumb and Comcare Decision No. 7770, 14 February 1992

Re Quinn and Australian Postal Corporation Decision No. 8047, 18 June 1992

Re The Hospital Benefit Fund of Western Australia and Department of Health, Housing and Community Services and Anor Decision No. 8076, 2 July 1992

Plumb v Comcare unreported, 18 September 1992, Federal Court, Full Court

Re Fuller and Comcare Australia Decision No. 8293, 7 October 1992

Blair v Curran [1939] HCA 23; (1939) 62 CLR 464

Commonwealth v Sciacca (1980) 17 FCR 476

Bogaards v McMahon [1988] FCA 161; (1988) 8 AAR 556

Administration of Papua and New Guinea v Daera Guba [1973] HCA 59; (1973) 130 CLR 353

Thrasyvoulou v Environment Secretary (1990) 2 AC 273

Bushell v Repatriation Commission unreported, 7 October 1992, High Court, Full Court, 92/035

East v Repatriation Commission (1987) 4 ALR 518

Repatriation Commission v Webb (1987) 76 ALR 131

Webb v Repatriation Commission (1988) 78 ALR 696

Repatriation Commission v Bushell [1991] FCA 185; (1991) 23 ALD 13

Repatriation Commission v Whetton [1991] FCA 472; (1992) 24 ALD 33

Registrar of the Court of Appeal v Maniam (No. 1) (1991) 25 NSWLR 459

Registrar of the Court of Appeal v Maniam (No. 2) (1992) 26 NSWLR 309

The determination under review is set aside. In substitution the Tribunal determines that the death of Mr Cruise from acute myeloblastic leukemia and polycythaemia rubra vera, a form of myeloproliferative syndrome, was war-caused and that in respect of her claim lodged on 5 October 1990 Mrs Cruise is entitled to payment of pension as his widow under the provisions of the Veterans' Entitlements Act 1986.

This is an application to review a decision of the Repatriation Commission made 27 November 1990 and affirmed by the Veterans' Review Board ("VRB") on 18 October 1991 which determined that the death of the applicant's husband, Laurence Cruise, was not war-caused within the meaning of that term in s.8 of the Veterans' Entitlements Act 1986 ("the Act").

2. At the hearing Mr D De Marchi, a solicitor appeared for the applicant. Mr A Smith, an officer of the Department of Veterans' Affairs, appeared for the respondent. The Tribunal received in evidence the documents ("the T documents") lodged pursuant to s.37 of the Administrative Appeals Tribunal Act 1975 (the "AAT Act") and the further exhibits tendered during the hearing. After the hearing the Tribunal noticed that two documents in the T documents were incomplete in that the last page of each appeared to be missing. A request was made to Mr Smith for those two pages and they were obtained. Mr De Marchi called Mrs Cruise who gave her evidence over the telephone. He also called Dr Parkin, a haematologist. At the conclusion of the hearing on Monday, 28 September 1992, leave was reserved to the parties to call further medical evidence. Mr De Marchi on 2 October 1992 lodged a submission to which was attached a further report by Dr Parkin.

3. The material contained in the T documents establishes that Mr Cruise was born on 11 April 1912 and that he served in the Royal Australian Air Force from 22 June 1943 to 25 October 1945. During that period he served in New Guinea from December 1943 to June 1945. On 1 May 1980 Mr Cruise was diagnosed as suffering from polycythaemia rubra vera ("PRV"). At that time the medical superintendent of Heidelberg Repatriation Hospital, in reporting to Mr Cruise's general practitioner on that diagnosis, suggested that a condition diagnosed as cirrhosis of the liver twenty-five to thirty years earlier may have been the early stages of PRV. In 1982 Mr Cruise was referred by the Repatriation General Hospital to Professor Penington at the University of Melbourne for a second opinion as to treatment of his PRV. Professor Penington wrote:

"I have no doubt that this man's polycythaemia vera goes

back to the 1950s and that it has become progressively more

troublesome in recent years."

Mr Cruise died on 24 July 1984. The death certificate gives the cause of death as:

"Acute myeloblastic leukemia - 8 weeks

Myeloproliferative syndrome - 10 years +"

It is not in dispute that PRV is a form of myeloproliferative syndrome and that acute leukemia occurs as a complication of PRV. Dr Parkin said in evidence that leukemia is a terminal event in something like 10 to 20 per cent of patients who have PRV.

4. For Mrs Cruise to obtain a war widow's pension it is necessary that her husband's death be taken to have been war-caused. Section 8 of the Act provides so far as relevant:

"8(1) Subject to this section, for the purposes of this Act,

the death of a veteran shall be taken to have been

war-caused if -

. . .

(b) the death of the veteran arose out of, or was

attributable to, any eligible war service rendered by the

veteran;

. . .

(d) in the opinion of the Commission, the death of the

veteran was due to an accident that would not have occurred, or

to a disease that would not have been contracted, but for his or

her having rendered eligible war service or but for changes in

the veteran's environment consequent upon his or her having

rendered eligible war service; or

(e) the injury or disease from which the veteran died -

(i) was suffered or contracted while the veteran was

rendering eligible war service, but did not arise out of that

service; or

(ii) was suffered or contracted before the commencement

of the period, or last period, of eligible war service rendered

by the veteran, but not while the veteran was rendering eligible

war service, and, in the opinion of the Commission, the injury or

disease was contributed to in a material degree by, or was aggravated

by, any eligible war service rendered by the veteran, being

service rendered after the veteran suffered that injury or

contracted that disease, but not otherwise."

5. Because Mr Cruise served overseas he rendered operational service within the meaning of that term in s.6 of the Act and therefore the relevant standard of proof is that provided in s.120(1) and s.120(3) of the Act. They read as follows:

"120(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."

"120(3) In applying sub-section (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. Before proceeding to consider the substantive issue in this matter it is necessary to deal with a procedural and evidentiary point which arises because on 8 May 1990 this Tribunal, differently constituted, ("the previous Tribunal") delivered a decision as to whether or not the death of Mrs Cruise's husband was war-caused, Re Repatriation Commission and Cruise (Decision No. 5881 of 8 May 1990). The previous Tribunal decided:

"The decision under review is set aside and, in substitution for it,

it is decided that the death of the respondent's

husband, Laurence Colgan Cruise, was not war-caused and

consequently pension is not payable to the respondent as his

dependant under the provisions of the Veterans' Entitlements Act

1986."

7. In order to give context to that decision and this application it is appropriate to set out the history of Mrs Cruise's claims to have her husband's death accepted as war-caused.

(i) Mr Cruise died on 24 July 1984.

(ii) On 26 September 1984 Mrs Cruise lodged a claim for

pension in which she claimed that her husband's death was

war-caused. She supported that claim with a lengthy statement

(T24, pp 57-58).

(iii) On 23 July 1985 Mrs Cruise's claim was rejected by a

delegate of the Repatriation Commission (T26, p 65). The

delegate relied on a report by a medical officer of the

Department of Veterans' Affairs (T25, pp 60-64).

(iv) Mrs Cruise sought review by the VRB on 27 August 1985.

(v) The matter was heard by the VRB on 30 July 1986 but was

adjourned to enable further medical evidence to be obtained.

(vi) On 28 October 1986 the VRB set aside the decision of

the Repatriation Commission and substituted a decision that

Mrs Cruise was entitled to a widow's pension with effect from

25 July 1984 (T27, p 67). In reaching that decision the VRB

referred to extracts from Mr Cruise's service file and medical

file and to a medical report by Professor Penington dated

1 September 1986 (T27, pp 75-76).

vii) The Repatriation Commission sought review of that

decision by this Tribunal.

(viii) The AAT on 8 May 1990 set aside the VRB decision

that Mr Cruise's death was war-caused and substituted a

decision that it was not war-caused.

(ix) On 5 October 1990 Mrs Cruise lodged a further claim for

pension in which she again sought to have her husband's

death accepted as war-caused under the Act.

(x) On 27 November 1990 a delegate of the Repatriation

Commission determined:

(T30, p 119)

"The matter of a causal link between the late veteran's

death and his war service had previously been considered by the

Administrative Appeals Tribunal as recently as 8 May 1990. The

Tribunal was satisfied, to the requisite standard of proof, that

no reasonable hypothesis of such a link had been established and

refused the widow's claim for a pension.

. .

Nevertheless I have reconsidered all of the available

evidence and I am of the opinion that the material before me

does not raise a reasonable hypothesis connecting the cause of

Mr Cruise's death with his war service. I am therefore satisfied

, beyond reasonable doubt, that there is no sufficient

ground for determining that his death was war-caused."

(xi) Mrs Cruise sought review of that determination by the

VRB.

(xii) On 18 October 1991 the VRB decided to affirm the

decision of the Repatriation Commission (T33, pp 122-127)

saying:

(pp 126-127)

"The argument Mr Horan had asked the Board to consider is as

follows: There is evidence connecting the cause of death with

the veteran's pre-existing condition of polycythemia. There is

also evidence suggesting a temporal coincidence between the

onset of this condition and war service. Against this

background a comment made by Professor Penington . . . can be

seen to establish a reasonable hypothesis, even in the presence

of divergent medical opinion. Professor Penington's comment is

that:

'The veteran's very poor diet and his general ill-health (on

service) would have contributed to the progress of the

polycythemia'.

In the Board's view, this contention was adequately dealt

with by the Administrative Appeals Tribunal in its decision

dealing with the applicant's previous claims when it stated as

follows:

'It is unfortunate that Professor Penington was not called to

give oral evidence so that he could amplify the statement in his

second letter referred to above. There is no evidence before

the Tribunal as to any mechanism by which poor diet or

ill-health could have contributed to, or aggravated, the

polycythemia or as to any research showing that it has done so

in other persons. It must, therefore, in our view remain a

matter of mere speculation, an hypothesis which is not pointed

to by any of the material before the Tribunal.'

In this respect the Board's notes the statement by the

advocate at the hearing that he was himself unaware of any

research which related poor diet or ill-health to the condition

polycythemia.

Having reviewed the whole of the material available to it

and for the reasons given above, the Board is of the opinion

that the evidence does not raise a reasonable hypothesis

connecting the veteran's death with the circumstances of the

particular service rendered. The Board therefore is satisfied

beyond reasonable doubt that there is no sufficient ground for

determining that the veteran's death was war-caused. In these

circumstances, the Board is required to affirm the decision

under review."

(xiii) On 30 December 1991 Mrs Cruise lodged an application

for review by this Tribunal.

(xiv) At a preliminary conference the Repatriation

Commission sought to argue that this Tribunal did not have

jurisdiction to review the determination of the Repatriation

Commission which was affirmed by the VRB. Subsequently, at a

callover to fix a date for the hearing of the jurisdictional

point, Mr Smith advised Deputy President Forrest that the

Repatriation Commission did not contest jurisdiction. Deputy

President Forrest therefore, on 1 July 1992 made the following

decision:

"Upon hearing Mr De Marchi, solicitor for the applicant

and Mr Smith, officer of the respondent, the Tribunal

decides that it has jurisdiction in this matter."

8. Where there has been an issue as to jurisdiction it is not impossible, although we hope it would be rare, that different members of the Tribunal may have different views as to whether or not the Tribunal has jurisdiction to deal with a matter. In this matter that did not present a problem as this Tribunal agrees that the Tribunal has jurisdiction under s.175 of the Act to review the Repatriation Commission decision made on 27 November 1990 and affirmed by the VRB on 18 October 1991. However a related difficulty arose at the hearing. Mr Smith said that if Mr De Marchi sought to raise any of the hypotheses that were rejected by the Tribunal previously he would be "raising res judicata at the end of the day". Mr De Marchi submitted that implicit in the decision of Deputy President Forrest was a decision that the findings of the Tribunal in the decision delivered 8 May 1990 do not give rise to any issue estoppel or res judicata in this hearing. In his final address Mr Smith clarified his submission. He said that if the Tribunal has already made a decision on a particular hypothesis then in the absence of new evidence as to that hypothesis, the finding on that hypothesis is covered by issue estoppel. However he added:

"But I do not really think it needs to apply - the facts and

the medical arguments that have unfolded in this case. So I

do not actually make a submission that it applies in this

particular proceeding."

9. The question whether or not any earlier decision of this Tribunal gives rise to issue estoppel or res judicata is a difficult one. It has been considered by the Tribunal on a number of occasions, some examples are Re Cooper and Commonwealth of Australia (1988) 16 ALD 213, Re Hopper and Australian Meat and Livestock Research (1990) 11 AAR 329, Re Bertram and Repatriation Commission (Decision No. 7188 dated 11 June 1991), Re Langley and Repatriation Commission [1992] AATA 73; (1992) 15 AAR 417, Re Plumb and Comcare (Decision No. 7770 dated 14 February 1992), Re Quinn and Australian Postal Corporation (Decision No. 8047 dated 18 June 1992), Re The Hospital Benefit Fund of Western Australia Inc. and Department of Health, Housing and Community Services (Decision No. 8076 dated 2 July 1992), and Re Fuller and Comcare Australia (Decision No. 8293 dated 7 October 1992). It has also recently been considered by the Federal Court in Plumb v Comcare (unreported Federal Court decision dated 18 September 1992) but unfortunately, although the Court has delivered its decision, its reasons are not yet available.

10. Dixon J (as he then was) explained the distinction between res judicata and issue estoppel in Blair v Curran [1939] HCA 23; (1939) 62 CLR 464 at page 532. He said:

"The distinction between res judicata and issue-estoppel is

that in the first the very right or cause of action claimed or

put in suit has in the former proceedings passed into judgment,

so that it is merged and has no longer an independent existence,

while in the second, for the purpose of some other claim or

cause of action, a state of fact or law is alleged or denied the

existence of which is a matter necessarily decided by the prior

judgment, decree or order."

In Commonwealth v Sciacca (1980) 17 FCR 476 at page 480 the Full Federal Court said:

"A finding by an administrative tribunal will not give rise

to an issue estoppel. In W J and F Barnes Pty Ltd v Federal

Commissioner of Taxation [1957] HCA 23; (1957) 96 CLR 294, Kitto J said (at 315)

that a taxation board of review's decision was not an

adjudication; it was administrative in character and could not

create an issue estoppel.

The question is not a straightforward one and it was not

fully argued before us. Because of our view that the judgment

of Gallop J did not give rise to any relevant issue estoppel, it

is unnecessary to decide the point and, accordingly, we express

no view upon it."

11. These cases were considered by Deputy President Thompson in Re Hopper at page 333 ff. He pointed out that Pincus J in Bogaards v McMahon [1988] FCA 161; (1988) 8 AAR 556 had cast some doubt on the proposition that a finding by an Administrative Tribunal will not give rise to an issue estoppel but had not decided the point as it was not necessary to the question immediately before the Court. Pincus J relied on Administration of Papua and New Guinea v Daera Guba [1973] HCA 59; (1973) 130 CLR 353. In his reasons for judgment in that case Gibbs J (as he then was) said at pages 453-454:

"The doctrine of estoppel extends to the decision of any

tribunal which has jurisdiction to decide finally a question

arising between parties, even if it is not called a court, and

its jurisdiction is derived from statute or from the submission

of parties, and it only has temporary authority to decide a

matter ad hoc.

In Carl Zeiss Stiftung v Rayner and Keeler Ltd (No. 2) (1967)

1 AC 909-910, Lord Reid said that it 'is clear that the earlier

judgment relied on must have been a final judgment, and that

there must be identity of parties and of subject matter in the

former and in the present litigation'." (emphasis added)

12. In our view that passage really decides this matter. While there may still be some question as to whether a finding by this Tribunal can give rise to an issue estoppel, there is no question but that it is only a "final judgment" which gives rise to an issue estoppel. In Thrasyvoulou v Environment Secretary (1990) 2 AC 273, at p 289, Lord Bridge of Harwich said:

"In relation to adjudications subject to a comprehensive

self-contained statutory code, the presumption, in my opinion,

must be that where the statute has created a specific

jurisdiction for the determination of any issue which

establishes the existence of a legal right, the principle of res

judicata applies to give finality to that determination unless

an intention to exclude that principle can properly be inferred

as a matter of construction of the relevant statutory

provisions." (emphasis added)

13. In this matter it is clear that the decision of the Tribunal delivered on 8 May 1990 did not "decide finally" the question whether or not Mr Cruise's death was a war-caused death. That is apparent from the provisions of the Act. Sub-sections 14(6) and (7) read as follows:

"14(6) Where:

(a) a person has made a claim for a pension under this

section in respect of the death of a veteran; and

(b) the claim has not been finally determined;

the person is not empowered to make another claim for a

pension under this section in respect of the death of that

veteran.

"14(7) For the purposes of this section, a claim is finally

determined when either:

(a) a decision that has been made in respect of the claim is

not subject to any form of appeal or review; or

(b) a decision that has been made in respect of the claim was

subject to any form of appeal or review, but the period within

which such an appeal or review could be instituted has ended

without an appeal or review having been instituted."

It follows from s.14(6) that once a claim for pension in respect of the death of a veteran has been "finally determined", as defined in s.14(7), another claim for pension in respect of that death may be made. There is no requirement that there be new evidence to justify the making of another claim. There would be no point in another claim being made if issue estoppel applied to require the decision maker and the Tribunal to reach the same decision as in the earlier matter. We therefore hold, applying Thrasyvoulou v Environment Secretary, that in this matter it can be inferred as a matter of construction of s.14(6) and (7) that the Act shows an intention to exclude the principles of res judicata or issue estoppel giving finality to the earlier decision of this Tribunal. Therefore the decision of the Tribunal delivered on 8 May 1990, that Mr Cruise's death was not war-caused, does not create an issue estoppel in this matter. We note that in Re Bertram, to which Mr Smith referred us, the Tribunal raised this question in the context of the Act, but concluded that it was not necessary for it to decide it because of the view it took of the evidence.

14. Having concluded that we are free to consider the evidence before us, unrestricted by the earlier decision in this matter, we turn to consider whether the whole of the material raises a reasonable hypothesis connecting Mr Cruise's death with the circumstances of his service. The unchallenged medical evidence is that the cause of PRV is not known. Thus if Mrs Cruise is to succeed it must be on the basis that although the cause of PRV is unknown, the whole of the material raises a reasonable hypothesis under s.8(e)(i) or (ii) that the disease which was suffered or contracted during Mr Cruise's service or before the commencement of his last period of service was contributed to in a material degree or was aggravated by his service.

15. After the Tribunal concluded its hearing of this matter the High Court on 7 October 1992 delivered a decision in Bushell v Repatriation Commission. That case concerned the application of the standard of proof in s.120(1) and 120(3) of the Act. The High Court made it clear that the fact that the cause of a disease is unknown will not prevent a reasonable hypothesis being raised connecting the disease with the circumstances of a veteran's service. Mason C.J., Deane J and McHugh J, in joint reasons for judgment, suggested that the fact that the cause of a disease is unknown will make it unlikely that a finding can be made that a hypothesis advanced by a "respectable medical practitioner" is unreasonable. Their Honours said (at pp 12-13):

"Whether the hypothesis of Dr Schiller and Dr Miller is right

or wrong, it could hardly be said that it was fanciful,

impossible, incredible, not tenable or too remote or too tenuous

unless it was established that there was no temporal connection

between the appellant's anxiety state and his hypertension. . .

. The hypothesis was supported by two eminent practitioners who

drew on scientific studies which championed the theory. It was

also conceded that 'some respectable medical practitioners'

accept the connection between stress and essential hypertension.

It is a connection which apparently also has the support of the

National Heart Foundation. True it is that the weight of

informed medical opinion is against the hypothesis. However,

the cause of essential hypertension is still unknown. In these

circumstances, a finding that the hypothesis was not reasonable,

although a matter for the Tribunal, is surprising." (emphasis

added)

16. In discussing what is required to raise a reasonable hypothesis their Honours, in their joint reasons for judgment, said (at pp 4-5):

"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. Clearly enough, a relevant consideration in forming an

opinion whether a particular hypothesis is reasonable is

whether, as a matter of common or medical experience, the

occurrence of an injury etc. of the kind sustained by the

veteran is commonly accompanied by or associated with the

occurrence of raised facts of the kind which constitute the

relevant incidents of the service of the veteran. However, a

hypothesis may still be reasonable even though such an

accompaniment or association is not demonstrated or even if it

is shown to be uncommon. So, in determining whether a

hypothesis is reasonable for the purpose of s.120(3), it is not

decisive that a connection has not been proved between the kind

of injury which occurred and circumstances of the kind which

constitute the relevant incidents of the veteran's service. Nor

is it decisive that the medical or scientific opinion which

supports the hypothesis has little support in the medical

profession or among scientists." (emphasis added)

Their Honours adopted the words of the Full Court of the Federal Court in East v Repatriation Commission [1987] FCA 242; (1987) 74 ALR 518 at p 533, saying:

"However, a hypothesis cannot be reasonable if it is

'contrary to proved scientific facts or to the known phenomena

of nature'. Nor can it be reasonable if it is 'obviously

fanciful, impossible, incredible or not tenable or too remote or

too tenuous."

"But leaving aside cases of those kinds, the 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. As we have earlier pointed out,

it is not the function of s.120(3) to require the Commission to

choose between competing hypotheses or to determine whether one

medical or scientific opinion is to be preferred to another.

This does not mean, however, that in performing its functions

under s.120(3) the Commission cannot have regard to the medical

or scientific material which is opposed to the material which

supports the veteran's claim. Indeed, the Commission is bound

to have regard to the opposing material for the purpose of

examining the validity of the reasoning which supports the claim

that there is a connection between the incapacity or death and

the service of a veteran. But it is vital that the Commission

keep in mind that that hypothesis may still be reasonable

although it is unproved and opposed to the weight of informed

opinion."

17. Brennan J, in Bushell's case (at page 19), also quoted with approval from East's case. He set out at greater length the relevant passage which was originally stated by the Veterans' Review Board and then adopted by this Tribunal and the Full Court of the Federal Court. The passage quoted by His Honour reads:

"A hypothesis may be conveniently defined as: 'proposition

made as basis for reasoning, without assumption of its truth;

supposition made as starting point for further investigation

from known facts; groundless assumption': The Concise Oxford

Dictionary.

. . .

The addition of the word 'reasonable' would however seem to

imply that what is required is more than a mere hypothesis. In

the opinion of the Board, to be reasonable, a hypothesis must

possess some degree of acceptability or credibility - it must

not be obviously fanciful, impossible, incredible or not tenable

or too remote or too tenuous. For a reasonable hypothesis to be

'raised' by material before the Board, we think it must find

some support in that material - that is, the material must point

to, and not merely leave open, a hypothesis as a reasonable

hypothesis."

18. Both Brennan J and Toohey J quoted with approval the exposition of the concept of a reasonable hypotheses by Beaumont J in Repatriation Commission v Webb (1987) 76 ALR 131 at page 135:

"It is hardly necessary to observe that the question whether

an hypothesis is 'reasonable' is one thing; to determine

whether, as a matter of professional opinion, that hypothesis

represents the preferred view is a different matter: a number

of opinions may be held by a number of experts in the field;

each view may be reasonably held notwithstanding that they may

lead to different conclusions. The point sought to be achieved

by the introduction into s.120 of the notion of a 'reasonable'

hypothesis is the distinction between a theory that is

rationally based, on the one hand, and an opinion or view that

is irrational, absurd or ridiculous, on the other. It is

possible, especially as here, where the aetiology of the disease

is unknown, to have more than one reasonable hypothesis advanced

which suggest different causes of the disease. The exercise is

not one of balancing or weighing the respective merits of a

range of professional opinions. Rather, it is a case of

determining whether the particular theory has a rational

foundation."

Although Beaumont J's decision was reversed by the Full Court of the Federal Court on appeal (Webb v Repatriation Commission (1988) 78 ALR 696), Toohey J in Bushell's case pointed out that the passage was not disapproved by the Full Court and Brennan J said that he agreed with the passage. Brennan J concluded, at pages 21-22:

"The purpose of s.120(3) is to ensure that, though fashion

in medical theories changes, veteran claimants who have had

operational service should not be prejudiced so long as there is

a reasonable hypothesis of connection favouring entitlement to a

pension. It would be an exceptional case in which it would be

right for the AAT, forming its own view of competing medical

theories, to hold an hypothesis of connection favouring

entitlement to be unreasonable, when the hypothesis is supported

by 'a responsible medical practitioner, speaking within the

ambit of his expertise'.

Although s.120(3) entrusts the determination of the issue of

reasonableness to the decision-maker, the decision-maker is

bound to have regard to its own want of scientific expertise in

comparison with the expertise of a responsible medical

practitioner who supports the reasonableness of an hypothesis

favouring entitlement."

19. Toohey J, in Bushell's case (at pages 32-33), considered the conclusion of the Full Court of the Federal Court in East's case:

"A reasonable hypothesis requires more than a possibility,

not fanciful or unreal, consistent with the known facts. It is

an hypothesis pointed to by the facts, even though not proved

upon the balance of probabilities."

His Honour, at page 34, adopted with approval an observation of Davies J in the Full Court of the Federal Court in Repatriation Commission v Bushell [1991] FCA 185; (1991) 23 ALD 13 at page 16, in which he said:

"However, although it is clear that the tribunal thought the

hypothesis propounded was wrong, it is difficult to determine

what the tribunal required of a reasonable hypothesis. The

tribunal did not say, eg that the theory put forward in respect

of Mr Bushell was fanciful. And, the tribunal did not expressly

say that it was satisfied beyond reasonable doubt, on the whole

of the evidence, that the hypothesis was unsound. There are

indeed passages which could suggest that the tribunal entered

into the arena of determining the validity of the hypothesis,

and did so on the balance of probabilities, rather than

determining, under s.120(3), whether the hypothesis was, as a

theory or supposition, reasonable and pointed to by the

facts."

20. Those passages from Bushell's case are consistent with comments of the Full Court of the Federal Court in Repatriation Commission v Whetton [1991] FCA 472; (1992) 24 ALD 33 where the court, at page 36, emphasised that the antithesis of a "reasonable hypothesis" is not a "speculative hypothesis" but an "unreasonable hypothesis" and said:

"Indeed an hypothesis is by definition speculative."

The Court referred to both the Shorter Oxford English Dictionary and Blakiston's Gould Medical Dictionary definitions of the word "hypothesis" and considered the two ways in which the Full Court in East said that an hypothesis can be uncertain:

"(a) because it postulates a medical principle in

circumstances not known to have definitely have existed in

the instant case, and

(b) because the medical principle is one which science,

although unable to describe (. . .) as unreasonable, is not

yet able to prove definitely."

It is case (b) which is relevant to this matter. As is apparent from the medical evidence, science is not able to prove definitely any medical principle which may connect Mr Cruise's service with the development of his PRV. The issue is whether the evidence raises a reasonable hypothesis of such a connection.

21. In his statement of case, Mr De Marchi set out the reasonable hypothesis on which he intended to rely as follows:

"It is submitted that the condition of polycythaemia rubra

vera, which developed into myeloblastic leukaemia was either

contracted by the Veteran while the Veteran was rendering

operational service, or was suffered or contracted before the

period of service, and was contributed to in a material degree

by the eligible war service or was aggravated by the period of

eligible service."

Both Professor Penington and Dr Parkin, in forming their opinions about this matter, had considered a statement made by Mrs Cruise as to her husband's health during and after service. In a statutory declaration made on 20 June 1986 she stated:

"On his return from war service in New Guinea he was a

physical nervous wreck being lethargic, tired and listless.

. . .

During his war service in the RAAF he constantly complained

in his correspondence to me that he found the food issued in his

Unit Mess was not to his liking. In fact, he seldom ate in the

Mess because he could not bear to eat the food. I sent him on

frequent occasions parcels of tinned food and home made food.

He also resorted to the nearby American Forces Canteen for

sustenance. My husband had constant (in)digestion and was

troubled with stomach pains and suffered with diarrhoea during

his service at Milne Bay. The deterioration in his health was

clearly shown by his appearance during a period of compassionate

leave granted to him during 1944, due to the serious illness of

his Mother. My husband's appearance was that of a sick man and

he had obviously lost a considerable amount of weight. On his

return to Australia during middle 1945 he again appeared to have

lost a great deal of weight, his nerves were very bad and he

found it hard to sleep and rest. He had bad nightmares yelling

and trying to climb the bedroom wall until I awoke him, then he

would walk around the house, it seemed for hours and chain

smoking all of the time. After some months in Australia he

regained his condition to be 168 lbs at the time of his discharge

but his nervous condition was terrible, and he was suffering

from stomach disorder with severe diarrhoea.

. . . When my husband had an haemorrhage and this occurred on

countless occasions, his drinking stopped for a time but in

fact he was truly never an abstainer from drinking alcohol.

. . .

Following his return from New Guinea he had recurrent

fevers, sweating etc which I regarded at the time as being the

effects of severe colds. I also observed on his return that he

had regular bouts of nausea as well as repeated bilious attacks

many of which happened on a daily basis."

In evidence Mrs Cruise confirmed the material in that statement. She was asked as to her husband's eating habits when he came home from New Guinea:

"Did he have trouble with his food then, when he came

home?---Well, not - no, not that I put up for him.

Right. So he ate what you put up during that time?---Yes.

He would, you know, eat it, but he didn't hang on to it very

long after at all. If you know what I mean, he was, as far

as I knew, he was always finicky from then on."

22. Professor Penington did not give evidence at the hearing, but we propose to consider his reports first and then to consider the later reports and evidence of Dr Parkin. There was no dispute about the fact that Professor Penington is an eminent haematologist. Dr Parkin said of him:

"Professor Penington would have a very good knowledge of this

disease.

. . .

Professor Penington was - has been a haematologist most of

his working life until recently and was an eminent haematologist

and was a professor of medicine at Melbourne University, at

St Vincent's Hospital, which was a department with a substantial

reputation in the field of haematology. And Professor Penington

would have to be considered very expert in this area."

23. As set out in paragraph 3 of these reasons, Mr Cruise was referred to Professor Penington for a second opinion as to treatment of his PRV in 1982. In a report of 3 July 1986, Professor Penington wrote:

"I have now perused the statement from Mrs Gwendoline Cruise

which indicates that when he returned to Australia from his war

service in 1945 that he was presumed by a doctor at that time to

be suffering from cirrhosis, had indigestion and subsequently

suffered from episodes of haemorrhage. The diagnosis of

cirrhosis is likely to have indicated that the spleen was

enlarged at the time the diagnosis was made and if it can be

established in which year this occurred, it is likely that this

would indicate that the polycythaemia was, indeed, well

established at that time. The subsequent course of his illness

clearly indicates that it was not cirrhosis and it is very

possible that the polycythaemia was already present whilst he

was in New Guinea and that this would have contributed to his

indigestion and his taking a very poor diet during that time.

The very poor diet and his general ill-health would have

contributed to the progress of the polycythaemia." (emphasis

added)

Thus it would seem that in that report Professor Penington advanced the hypothesis that the disease of polycythaemia was suffered while Mr Cruise was rendering eligible war service, but did not arise out of that service, and was contributed to or aggravated by his poor diet and general ill health during service. There is evidence of general ill health during service in the T documents. In a report of a clinical examination performed on 23 October 1945, prior to his discharge, Mr Cruise was recorded as having suffered an ulcer on right shin which required treatment for nearly five months during service. The doctor also noted marked hand tremors, papular eruptions on the palms of each hand, and enlarged tonsils (T docs, pages 11 and 12). In her evidence Mrs Cruise recalled her husband's significant weight loss on his return home and his complaints of tinea, dysentery and diarrhoea during service in New Guinea (transcript, page 11). There is a medical report relating to an examination on 23 June 1955 on which Mr Smith relied. In it the doctor has recorded that Mr Cruise mentioned only one diarrhoea attack during service and said "whole unit had it". The report also states "never liked mess food, no symptoms while away on service". There is some conflict between this report and Mrs Cruise's evidence. Neither Mr Cruise nor the doctor were available to explain the history recorded in that report. We prefer the evidence of Mrs Cruise and accept her account of her husband's description of complaints on service.

24. Professor Penington wrote a further report of 1 September 1986, but it adds no more to the hypothesis advanced in the earlier report. He wrote:

"It appears very probable that he had established

complications of the disease in 1955 and if this were so, it is

quite probable that the disease was first active at least ten

years earlier as it is a very indolent condition. It is not

uncommon for essential thrombocythaemia to evolve to

polycythaemia vera after an interval of very many years and for

myelofibrosis then subsequently to develop.

It is quite true that the cause of the disease is unknown

but current research strongly points to the possibility of

retroviruses or through oncogenes. If, as I believe is highly

probable, the disease was well established in 1955 there is no

question that 'it did begin about 1955' as Dr Cooper seems

willing to concede.

I can make no further comment as to whether the war service

could have contributed to evolution of the disease but I do

believe it is likely that his disease commenced more than ten

years before the first period of complications associated with

gastrointestinal bleeding and would have to point out that the

diagnosis of 'cirrhosis of the liver' made at that time was

clearly proven to be incorrect by the fact that liver failure

did not develop in the subsequent twenty-nine years despite his

other serious physical problems." (emphasis added)

25. When this matter came before the previous Tribunal in May 1990 it received in evidence a further report from Professor Penington dated 20 August 1987. He stated that the VRB decision showed some misunderstanding of the medical evidence, but he also commented that "inappropriate and incorrect medical advice" was tendered to the VRB by the Department of Veterans' Affairs. Unfortunately, instead of stating the specific misunderstanding and explaining in what way advice tendered to the VRB by the Department of Veterans' Affairs was "inappropriate and incorrect", Professor Penington simply reiterated his own views. He wrote:

"There is no proof that myeloproliferative disorders are due

to retroviruses or oncogenes but there certainly is basic

biological evidence which makes this very possible.

There is clear evidence that diseases such as thrombocythaemia

and polycythaemia can run a course of 40 or 50 years. The

symptoms from which Mr Cruise suffered in the early 1950's in

retrospect are very probably due to myeloproliferative disease

which was later diagnosed even though they were not recognised

as such at the time. This is a common finding and my experience

in dealing with patients with this disease would be far greater

than that of the medical expert from the Commission who took a

different view on this matter.

In the event that the disease was causing major complications in

the early 1950's, it would have been present some ten years

earlier. In the event that it was an infective cause in the

form of retroviruses or acquired oncogenes, these would have

been acquired many years before the patient had symptoms

directly attributable to the disease.

I would not regard the dysentery which he suffered in New

Guinea as evidence of retrovirus infection. However, he would

have been exposed to various other infections during his period

of service in New Guinea."

Professor Penington then concluded that report with the following sentences:

"To make the argument now primarily based on whether the

dysentery was due to a retrovirus would, I believe, grossly

unjust. This is a difficult area for a lay tribunal to

understand and it would be misleading to argue just on that

point." (emphasis added)

That report neither repeated nor withdrew the hypothesis advanced in the report of 3 July 1986 that conditions of service would have contributed to the progress of Mr Cruise's PRV.

26. The reasons for decision delivered by the previous Tribunal show that the passage in Professor Penington's report, as to conditions of service contributing to the progress of Mr Cruise's PRV, was discussed during Professor Fox's evidence. The reasons read as follows:

"As already noted, Professor Penington stated in his second

letter that 'the (veteran's) very poor diet and his general

ill-health would have contributed to the progress of the

polycythaemia'. Professor Fox thought that Professor Penington

had not intended to infer that the veteran's poor diet and

general ill health was causative; he wrote: 'it would be

difficult to state exactly how much these factors contributed to

the progress of the disease (which actually appears to have run

a very long course e.g. at least 30 years, possibly 40 years)'."

(emphasis added)

Unfortunately the Tribunal in this matter did not have before it Professor Fox's report. Professor Fox was not called before this Tribunal, although the reasons for the earlier Tribunal decision were received into evidence in this matter. It does however appear from the passage quoted above that Professor Fox did not regard the hypothesis that the conditions of Mr Cruise's service may have contributed to the progress of his PRV as fanciful or unreal or unreasonable. Nor did he describe it in the words of Beaumont J in Webb's case as irrational, absurd or ridiculous. On the contrary, he gave it qualified support. He did not deny that the factors contributed to the progress of the disease, but he said that it was difficult to qualify that contribution and he pointed out that the disease had run a very long course.

27. Dr Parkin is the chairman of the division of laboratory services at Heidelberg Repatriation Hospital. He has been a practising clinical and laboratory haematologist for twenty-two years. He read the T documents in this matter and wrote a report on 18 September 1992. In the body of the report he wrote:

"With a very considerable experience of PRVera I have only

seen one patient who survived this length of time from

diagnosis. This individual was also an ex-serviceman who had

PRVera diagnosed during war service. I also draw attention to a

case recorded by Weinberg (1989) which involved a US Naval

rating who served during nuclear weapons tests in The Marshall

Islands age 19-23 years. At 34 years or before he developed

PRVera which was attributed to radiation exposure and he was

alive and well 23 years later. I mention this case not to invoke

radiation as a factor but to illustrate the atypical onset and

survival in relation to a specific environmental factor

impacting on a serviceman in the tropics."

28. In evidence Dr Parkin explained why he agreed with Professor Penington that the diagnosis of cirrhosis of the liver made in 1955 was a wrong diagnosis. He also agreed with the diagnosis of PRV. Dr Parkin said that there were a number of indications that Mr Cruise may have had his PRV in the 1950s or earlier. There was the enlargement of the liver which was wrongly diagnosed as cirrhosis in 1955, gastro-intestinal bleeding which was reputed as occurring in the 1950s, the fact that in 1980 Dr Duggan recorded that Mr Cruise said he had suffered from gout for fifteen to twenty years and the history given by Mrs Cruise that her husband had loss of weight, fever and sweats following his return from New Guinea. Dr Parkin said that those conditions are a common accompaniment of PRV. Because Mr Cruise regained his lost weight, Dr Parkin gave less emphasis to that problem than to the fever and sweats. He thought the unexplained sweats on return from the islands could suggest that Mr Cruise had PRV at that time. He said:

"Well, fevers and sweats are very common symptoms. And

there are a lot of causes of fevers and sweats. But most people

that have had substantial disease which causes fevers and sweats

have an identifiable disease. And at no time was the cause of

this man's fever or sweats identified. So we would have to

presume that they were caused by some substantial but

unidentified problem, and that substantial and unidentified

problem may have been polycythaemia. I mean you are asking me

about science. I do not think that this is science. This is my

speculation based on my knowledge and experience. It is not

science."

"I can only say what I said before, that night sweats and

chills and fevers are very, very substantial symptoms and

usually have a very significant cause. But in the absence of

any other significant cause, such as recurrent malaria, for

example, then one would have to presume that the significant

disorder that he had was the most likely reasonable explanation

for those sweats and fevers."

There was also evidence from Mrs Cruise that by about 1950 or 1951 Mr Cruise suffered from impotence. Dr Parkin said that complications of PRV could give rise to that outcome.

29. Dr Parkin was told that in her telephone evidence at the hearing, Mrs Cruise had said that during and after service her husband had trouble with his food and that after service he vomited after a heavy meal. Mrs Cruise said that prior to his service Mr Cruise used to eat her mother's roast dinners but he did not eat them after service. Dr Parkin said that patients who have very enlarged spleens have nausea and discomfort after a large meal, so that symptom also supported the diagnosis of PRV on return from service. He agreed with Professor Penington's opinion that if Mr Cruise had major complications of the disease in the 1950s it could have been present ten years before. He said that if Mr Cruise's liver was substantially enlarged in 1950, it is likely that the disease process was very well established at that time. He said that would mean that he had had the disease for at least three years and maybe ten-fifteen years prior to that time.

30. Dr Parkin explained how an unsatisfactory lifestyle in the tropics may have enhanced the likelihood of Mr Cruise developing complications of PRV. He said:

"(P)olycythaemia rubra vera is a disorder which has many

complications, prominent amongst which is bleeding and

thrombosis and I imagine situations of poor nutrition, stress

and privation could set the background for gastric ulceration

which might be exacerbated by polycythaemia similarly to

pathology which involved the lower limbs which was common in the

island, tropical ulcers and such like may predispose to

thrombosis which is a very common complication of

polycythaemia."

"I can't say that I am aware of any evidence where a

lifestyle would actually cause the disease, only that it might

aggravate the complications of the disease."

Dr Parkin said that the gastro-intestinal bleeding in the 1950s would most likely have been due to peptic ulcer. In cross-examination Mr Smith asked Dr Parkin about the relationship between peptic ulcer and PRV. Dr Parkin replied:

"Peptic ulcer is a complication of polycythaemia rubra vera.

. . .

In someone who was predisposed to develop a peptic ulcer by

virtue of the fact that they have polycythaemia rubra vera,

another factor which also led to ulcers such as stress would

increase the likelihood of developing an ulcer. So I would

think that in that way one could see an interaction between his

environment and the complications of his disease."

31. Mr Smith also asked Dr Parkin about thrombosis as a complication of PRV. Mr Cruise developed a venous thrombosis at some stage in his later life. Dr Parkin replied that "previous thrombosis is one of the most potent causes of subsequent thrombosis" and added that thrombosis is a common complication of PRV. At the time Dr Parkin gave evidence it was not put to him that the service records show that Mr Cruise did have a tropical ulcer during service. The Tribunal therefore gave leave for Dr Parkin to provide a further report dealing with that and other specified matters and agreed to take that report into evidence after the close of the hearing. It was received on 2 October 1992 and became Exhibit A4. In it Dr Parkin wrote:

"Tropical ulcers are usually solitary ulcers on the lower

third of the leg and foot. They are associated with minor

injuries and poor conditions and the cause is unknown.

Ulcers are not a prominent feature of PRVera. However

venous thrombosis is a very common complication of PRVera and

leg ulcers are a common consequence of venous thrombosis. In

addition circulatory disturbance leading to death of tissue and

ulceration may occur in PRVera without major vessel

thrombosis.

In so far as tropical ulcers do not have a precise, defined

cause it is reasonable to say that the ex-members leg ulceration

may have been a manifestation of PRVera. On the other hand

ulcers were a common problem among serviceman (sic) in the

tropics."

32. During the hearing Dr Parkin was asked about the significance of tinea which is recorded during service. He replied:

"(T)inea is a disorder that may on the one hand be entirely

trivial and on the other hand, particularly in someone who might

be immuno suppressed, a very substantial pathology in the legs.

So if in fact he had tinea when he was in the islands and this

tinea was of a very substantial nature, then I guess that it

could set the background for other complications in his legs

such as thrombosis."

Dr Parkin was asked to comment on an entry at page 18 of the T documents relating to a medical examination in 1955 when peeling between the toes and superficial varices were noted. He said:

"Varices are veins - superficial veins that are dilated,

elongated and tortuous; that is the definition of them. I

mean, varicose veins - that is what is being talked about - and

varicose veins are a factor in leading to people developing both

superficial and deep vena thrombosis."

33. Mr De Marchi asked Dr Parkin to comment on the key passage in Professor Penington's report of 3 July 1986 where Professor Penington wrote:

"The subsequent course of his illness clearly indicates that

it was not cirrhosis and it is very possible that the

polycythaemia was already present whilst he was in New Guinea

and that this would have contributed to his indigestion and his

taking a very poor diet during that time. The very poor diet

and his general ill-health would have contributed to the

progress of the polycythaemia."

"I do not know what the professor is driving at in terms of

that. I mean if he is talking about complications, which was

what I was talking about previously, I can understand there are

a whole blether of complications of polycythaemia which might be

aggravated in someone who had a very poor and debilitate

lifestyle. But the actual progress of the disease I am not in

any way aware that the disease progression would be influenced

by hygiene and poor nutrition and factors like that."

34. In answer to questions from the Tribunal, Dr Parkin said that events which occurred during service may have been additive to the effect of a retrovirus. He explained the role of a retrovirus as follows:

"(R)etroviruses are viruses which actually gain access to a

cell and insinuate themselves into the actual genetic material

of the cell and stay dormant there for many years but can become

active and actually have the products of those viruses expressed

in the cells, some of which clearly can cause a cell to become

malignant. So that this activity of retroviruses may be a very

insidious activity. They are not necessarily associated with

clinical infection or clinical infection that we can time in

relationship to the cancer."

When asked to say what events during service may have been additive he said:

"I cannot identify those events because in asking me to

identify them is really the same as asking me do I know the

cause of the disease. Which I do not know. But I can make two

observations in relation to this man's disease. One is that the

median age, the kind of average age of onset of this disease is

in the sixth decade of life. There is lots of evidence to

support that. Although the incidence can occur from very young

to very old, it is mostly people in their fifties, sixties,

seventies. So it is a disease of older people. And for

somebody to develop this disorder when they are in the twenties

or thirties would suggest to me that some environmental factor

was acting in that case, which was different to the

environmental factors which acted in people who developed the

disease at the age of sixty, which is a very common event. I

have had very substantial experience in looking after people

with polycythaemia rubra vera and I have never seen it actually

presenting in a person under the age of 40. Now it is recorded

that it often does. I have not seen it in my experience. So it

is disease of old people. So I would like to make the point

that a man developing this disorder in his twenties or thirties,

I would have (to) think is there something in his environment or

lifestyle which is different. And clearly military service

could have been such an event. The other point about this

disorder is the average age of survival. And most patients the

median survival of polycythaemia rubra vera is somewhere around

10 to 14 years. So, most people who develop it at the age of

sixty die with it in their seventies. This man in fact lived

with this disease for many many years. So not only did it occur

at a very young age, but it actually pursued a very indolent

natural history which would also to my mind make the disease

unusual. Not very very rare, but very unusual. So that there

is two factors in this man. The fact that he developed the

disease when he was very youthful, and the fact that the disease

pursued a surprisingly indolent course would suggest to me that

intrinsic within the disease and the cause of it were factors

which are not factors which operate normally. Now that is

speculation, but I think reasonable speculation." (emphasis

added)

In answer to the question whether the disease might have run a different course if Mr Cruise had not had his experience of war service, Dr Parkin replied:

"I guess - that's the point that I was trying to make; that

it came on at a very young age, that it pursued a very unusual

natural history, therefore it was reasonable to look in his

lifestyle for some factor that was different in him to other

people who develop polycythaemia rubra vera; and the only

momentous thing in his life was military service in the

tropics." (emphasis added)

35. The issue in this matter is whether the evidence "raises a reasonable hypothesis connecting the disease PRV with the circumstances of Mr Cruise's service". The relevant connection, Mr De Marchi contended, was that provided in s.8(1)(e)(i) or (ii) of the Act. The previous Tribunal, in its reasons for decision of 8 May 1990, said as to the key passage of Professor Penington's report:

"There is no evidence before the Tribunal as to any

mechanism by which poor diet or ill health could have

contributed to, or aggravated, the polycythaemia or as to any

research showing that it has done so in other persons. It must,

therefore, in our view remain a matter of mere speculation, an

hypothesis which is not pointed to by any of the material before

the Tribunal."

36. However, as already stated, since the earlier decision in this matter the Federal Court has, in Whetton's case, clarified the meaning of "reasonable hypothesis" and has emphasised that an hypothesis is not to be rejected because it is mere speculation, so long as it is raised by the material before the Tribunal. The High Court in Bushell's case has endorsed that approach and has also emphasised that the fact that the cause of a disease is unknown (or, no doubt, also that contributing or aggravating factors to a disease are unknown), is no bar to the raising of a reasonable hypothesis connecting the disease with the circumstances of a veteran's service. In fact in their joint judgment Mason C.J. Deane J and McHugh J suggested that where the cause of a condition is still unknown, a finding that a hypothesis is not reasonable, although a matter for the Tribunal, is surprising. In this matter Professor Penington clearly advanced the hypothesis that:

"The very poor diet and his general ill-health (during

service) would have contributed to the progress of the

polycythaemia."

37. So far from describing that hypothesis as "fanciful, impossible, incredible or not tenable or too remote or too tenuous", Dr Parkin gave examples of ways in which the conditions of Mr Cruise's service could have caused or contributed to complications of the disease or could have rendered a dormant retrovirus active. He also specified matters, namely the unusually early age of onset and the unusually lengthy course of the disease after Mr Cruise had completed his service, which he thought pointed to the hypothesis that military service in the tropics could have been active in determining the time when Mr Cruise developed the disease. In his report of 18 September 1982 Dr Parkin also commented on the only other case of early onset of PRV and long survival which he had personally seen and on one other similar case reported in the medical literature, as examples of the "atypical onset and survival in relation to a specific environmental factor impacting on a serviceman in the tropics." As already stated, Professor Fox also gave some qualified support to the hypothesis advanced by Professor Penington and certainly did not describe it as unreasonable.

38. In these circumstances we conclude that the whole of the material before us does raise a reasonable hypothesis connecting the disease with the circumstances of the particular service rendered by Mr Cruise. We are satisfied that the evidence raises a reasonable hypothesis that the disease of PRV was suffered while Mr Cruise was rendering war service but did not arise out of that service but that the progress of the disease was contributed to in a material degree by Mr Cruise's service after contracting the disease, even though it was not diagnosed until much later.

39. The High Court in Bushell's case said (at p 6):

"But once the material raises such a hypothesis, the

operation of s.120(3) is spent and the case falls to be

determined in accordance with s.120(1). That is to say, the

Commission must determine that the injury etc. was war caused

unless it is satisfied beyond reasonable doubt that there is no

sufficient ground for making the determination."

There is no evidence satisfying us beyond reasonable doubt that there is no sufficient ground for making a determination that Mr Cruise's death was war-caused. The determination under review will therefore be set aside. In substitution the Tribunal determines that the death of Mr Cruise from acute myeloblastic leukemia and polycythaemia rubra vera, a form of myeloproliferative syndrome, was war-caused.

40. The Tribunal gave serious consideration to the question whether, if the evidence did not raise a reasonable hypothesis, it should, in accordance with the comments of Brennan J in Bushell's case, itself compel the production of further material by summonsing Professor Penington to ask him to explain what he meant by the "key passage" in his report. The Tribunal during the hearing on a number of occasions suggested to the parties that Professor Penington should be called so that the Tribunal would not, in Professor Penington's own words, be "grossly unjust" (see paragraph 26). Our finding means that it is not necessary for the Tribunal to call Professor Penington of its own initiative. When the Tribunal offered during the hearing to issue a summons requiring Professor Penington's attendance if either of the parties desired to have him called, both parties expressed the view that he would not come willingly and appeared reluctant to have a summons served on him. Mr De Marchi, in a further submission lodged with leave of the Tribunal on 2 October 1992, wrote:

"The Tribunal noted that it would be desirable that

Professor Penington be contacted to see whether he was available

to provide some clarification on his earlier reports. A

facsimile was forwarded to the Professor, enclosing copies of

his previous reports contained in the 'T' Documents.

On the 29th September, 1992, the Professor telephoned our

office and left a message that he was not available to give

evidence."

41. Although the Tribunal has decided this matter without the need to call Professor Penington as a witness, we feel that we should point out that it is not appropriate for a potential witness to decide whether or not he or she is "available" to give evidence in a matter. A potential witness, particularly where that potential witness has given a report setting out expert opinions designed to assist the Tribunal in deciding a matter, must make himself or herself available to give evidence in response to a properly served summons, unless factors like ill-health or absence from Australia make that impossible (see Registrar of the Court of Appeal v Maniam (No. 1) (1991) 25 NSWLR 459, Registrar of the Court of Appeal v Maniam (No. 2) (1992) 26 NSWLR 309.

42. The decision under review will be set aside. In substitution the Tribunal will determine that the death of Mr Cruise from acute myeloblastic leukemia and polycythaemia rubra vera, a form of myeloproliferative syndrome, was war-caused and that in respect of her claim lodged on 5 October 1990 Mrs Cruise is entitled to payment of pension as his widow under the provisions of the Veterans' Entitlements Act 1986.