Fairchild v Glenhaven Funeral Services  UKHL 22
Acknowledgement of the increased material risk of harm test as an exception to the but for test.
Three separate claimants contracted lung cancer (malignant mesothelioma) as a result of their exposure to asbestos during their various courses of employment with varying employers. Significantly, once an asbestos fibre has implanted in a human lung, it has an extended latency period whereby it can take decades before it causes a cancerous tumour which in turn then may take another near decade to cause the victim any distress. By the point at which symptoms emerge, the cancer is in too late a stage to be deemed treatable. Only a single incident of exposure to asbestos fibres is necessary for the cancer to be caused and subsequently repeated or prolonged exposure does not impact the severity of the cancer. Whilst the three claimants had all experienced asbestos exposure with each employer, it could not be determined which employer was the most likely source of the causative asbestos fibre.
From which employer, if any, were the claimants entitled to claim compensation from for their tortious negligence in exposing their employees to asbestos.
The House of Lords held that where a claimant could satisfy the burden of proof that one employer had materially contributed to their asbestos exposure, and thus had materially raised the probability of the claimant contracting cancer, the claimant could claim total compensation from them (although that employer may claim joint contributions from the other employers). The bench deemed that here it would have been inherently unjust to deny the claimants any remedy. Thus, where the facts are such that the ‘but for’ test cannot be reasonably or fairly applied, the ‘materially increased risk’ of harm test may be used.