Amaca Pty Ltd v Booth; Amaba Pty Ltd v Booth  HCA 53. Heydon J.
93. Mesothelioma is a painful illness leading to death. It is a cancer of the lining of the lung. It is very commonly caused by inhaling asbestos fibres, though perhaps not always.
It can be caused by very brief intense exposures whether occupational, domestic or recreational, and by lower-level environmental exposures – sometimes after exposures which are very short – a day – or very slight. On the other hand, many people can have heavy and sustained exposures to even the most dangerous types of asbestos without suffering the disease.
This phenomenon, like much else about the disease, is something which scientists have found difficult to explain. The disease has a latency period of at least 10 years, and sometimes much longer – as long as 75 years.
The disease is often not diagnosed until many years after exposure to asbestos.
It is therefore difficult for plaintiffs suffering from mesothelioma to establish the facts necessary for success in negligence actions.
In particular it can be difficult for them to establish that the conduct of a given defendant caused the disease.
A related difficulty for plaintiffs springs from the fact that the earlier the exposure the greater the chance that it could cause harm.
Because of the valuable characteristics of asbestos, particularly its capacity to retard fires, it has been commonly used until quite recently.
The extent of exposure to asbestos amongst those now living, the likely exposure amongst those yet to be born, and the likelihood of further injury taking place when asbestos is removed from the many places where it is now found, mean that problems of the kind thrown up in these appeals will remain for decades to come.
Perhaps a social-medical problem of this size requires a legislative solution.
In some places solutions have been sought in judicial or legislative changes to the law relating to causation.
New South Wales is not one of those places. In New South Wales a special court called the Dust Diseases Tribunal has been established. It has attracted considerable admiration for the energy it throws into the urgent resolution of controversies involving dying plaintiffs.
But it is bound by the general rules of causation in negligence. The question which these appeals raise is whether the Tribunal's causation findings in this case, and cases like it, are supported by any evidence.