Pethick v Commonwealth

The appellant when he entered on his service was a healthy and sound young man except that it is a reasonable hypothesis that there was a defect of the aortic valve from which there was an undetected murmur. The illness the onset of which occurred on 23rd October 1956 when he was placed in hospital was not bronchitis but was in fact sub-acute, or acute, bacterial endocarditis. There was then an involvement of the aortic valve. Bacterial endocarditis may be caused by an infection of any of a number of descriptions of organism; one which is commonly responsible is streptococcus viridans. But all that can now be known of the particular organism affecting the appellant's heart is that it was penicillin sensitive. An organism giving rise to bacterial endocarditis, being in the blood stream, lodges in the heart valve and multiplies, thus setting up the inflammation which impairs the valve. The treatment with penicillin at the hospital at the Woodside camp repressed the infection but the use of penicillin was not kept up long enough, as it may be inferred, to eliminate the organism and the appellant's relapse on 31st December 1956 should be regarded not as due to a re-infection but as a recurrence of the same infection manifested in the bacterial endocarditis. It was at this stage that the murmur or regurgitation was heard. When a cardiologist examined the appellant on 21st January 1957 a gross diastolic murmur was apparent, pointing to the incompetence of the valve as a result of disease.

It is the opinion of the cardiologist that he has "virtually no functioning aortic valve". "Normally when the left ventricle contracts it forces blood through the aortic valvae into the aorta; thereupon the aortic valve shuts, preventing blood from regurgitating back into the left ventricle." An infection present in the blood stream may come from any one of many sources; it may, for example, come through the mouth or a bacterial reservoir in the nose or throat or elsewhere, but unless there is a defect in the valve, whether congenital or acquired from rheumatic disease or otherwise, it is unlikely to find a lodging there. That is why it is a reasonable hypothesis that some antecedent defect already existed in the appellant's aortic valve. A bacterial colony once lodged in the valve may grow fast or slowly according to the virulence of the bacteria. How or when the bacteria entered the appellant's body it is impossible to say, but there are grounds in his case history for thinking that once the infection lodged in the aortic valve the development was rapid. On the other hand it is not possible to say that the valve had been much impaired by inflammation before the bacterial development was checked in the Woodside camp hospital by the use of penicillin.

In these circumstances the question is whether the appellant can sustain a claim for compensation under s. 9 of the Commonwealth Employees' Compensation Act 1930-1959. Section 9 deals with personal injury by accident arising out of or in the course of the employment. Section 10 deals with compensation for incapacity due to disease but it is clear that the appellant's case is outside its application. For it is a necessary condition of the application of s. 10 that "the disease is due to the nature of the employment in which the employee was engaged by the Commonwealth". Clearly enough bacterial endocarditis is not a disease due to the nature of military service or training.

But the appellant's difficulties in bringing his case under the operation of s. 9 are very great indeed. He must show that personal injury by accident arising out of or in the course of his employment by the Commonwealth was caused to him. There is little difficulty in his satisfying the requirement that there shall be "injury". But it must be injury by accident and it must arise in the course of the employment or else out of it. The appellant's difficulties in satisfying this condition appear insuperable. There are three "events", supposed or real, laid hold of by the appellant as amounting to "injury-by-accident". The first is the entry of the bacteria causing the infection into the appellant's body. The second is the lodgment of the organism in the aortic valve, the involvement of the valve in the infection. The third is the pathological impairment or destruction of the valve as a physiological mechanism.

On the facts to be inferred or assumed as to the inception and progress of the disease it seems to be plain that for one reason or another none of these three events supplies a basis for the application of the phrase "injury by accident arising out of or in the course of" his employment. It is convenient to deal with the three "events" in the reverse order.

Now it seems clear enough that there is no sufficient ground for inferring that the impairment or destruction of the aortic valve took place before the appellant was discharged from the camp, on 22nd November 1956, and returned to his civil occupation. True it is that he complained that in the sports he became breathless and he was not as equal to exertion as before his illness. But that is compatible with the general theory of the antecedent condition of his heart and his exertions and the activities he actually pursued were hardly consistent with the view that there had by that time been a serious impairment of the heart. It is therefore impossible to treat this "event" as occurring at a time when it could form accidental injury arising in the course of the employment. There is no causal connexion which would make it possible to treat it as an accidental injury arising out of the employment.

The second event postulated by the appellant is the settlement of the infection in and about the valve. Perhaps it is possible to infer or presume that this took place after he was called up and during his so-called employment on or before 23rd October 1956, although to do so hardly takes into account the possible logical effect of three short periods of leave in that time. But even so it is plain that there was nothing in the inception and progress of the infection of the valve prior to the pathological impairment of the valve which could constitute injury by accident.

The first of the supposed events, the entry of the bacteria into the body of the appellant, seems even more out of the question as a thing constituting an injury by accident arising out of or in the course of the employment. The source of the bacteria, when and how they got into the blood stream, and how it came that they found a lodgment in the heart are undiscoverable. It is a hypothetical event which cannot be brought into any causal or temporal connexion with the employment. There are of course reported decisions, particularly of a time when courts were less accustomed than now to bacteriological explanations, describing the process of infection in terms appropriate enough to accidental injury although they must read strangely to a microbiologist. But we need not concern ourselves with these authorities, for in this case there is nothing to show that any bacterial infection had an origin arising out of or in the course of the employment.

It is only necessary to add two observations. In the first place, if it matters, the general burden of proof rested upon the appellant before the Local Court, notwithstanding the earlier determination of the Delegate of the Commissioner. That determination might be used for its evidentiary value, but it could not throw over the legal burden of proof. In the second place, the appellant failed to establish a case not because of The Commonwealth v. Ockenden [1] but independently of any effect that may have been ascribed to that decision which has since been discussed in this Court in Kavanagh v. The Commonwealth [2] and The Commonwealth v. Hornsby [3] .

1. (1958) 99 C.L.R. 215. 2. (1960) 103 C.L.R. 547. 3. (1960) 103 C.L.R. 588.

I agree in the reasons for judgment of the Chief Justice and am of the opinion that the appeal should be dismissed.