In Heneghan v Manchester Dry Docks Ltd & Ors [2016] EWCA Civ 86, the Court of Appeal considered whether the Fairchild exception should be applied in a case of multiple exposures to asbestos leading to lung cancer. Like mesothelioma, lung cancer is regarded as an “indivisible” disease – the severity does not depend upon the exposure to asbestos.

Mr Heneghan was exposed to asbestos by the six defendants, who were responsible for 35.2% of the whole exposure over Mr Heneghan’s working life. The claimant died of lung cancer. It was common ground that the cancer was caused by his exposure to asbestos; that he was exposed to asbestos while he was employed successively by each of the defendants; that biological evidence cannot establish which (if any) of the exposures actually caused the disease; but that epidemiological or statistical evidence can establish by how much the exposure attributable to each defendant increased the risk that he would contract the disease.

The Court of Appeal identified the two stages of the causation question. The first question (the “what” question) is what probably caused the lung cancer. It was not in dispute that the epidemiological evidence showed that on the balance of probabilities the deceased’s exposure to asbestos was the cause of his lung cancer. The second question (the “who” question) arises in a multi-contributor case where the issue is which contributor’s asbestos caused the cancer. It was common ground that it could not be proved that the exposure attributable to any individual defendant had doubled the risk (and thus satisfied the necessary degree of probability) that Mr Heneghan would develop lung cancer. In the circumstances, the Court of Appeal decided that the Fairchild exception was the correct test for causation. In this case, causation was established as each defendant had materially increased the risk of the victim contracting lung cancer.

The result was that each defendant was liable. The issue of apportionment of liability under the Fairchild exception had been addressed in the House of Lords in Barker v Corus; it was decided that a defendant was liable only in proportion to his own contribution to the exposure to the asbestos and therefore to the risk that the deceased would contract mesothelioma. Section 3 of the Compensation Act 2006 had reversed this aspect of Barker and had substituted joint and several liability for the whole of the damage. However, the Compensation Act applies only to mesothelioma. Therefore, in relation to lung cancer, the Fairchild exception resulted in each defendant being liable only for the exposure for which it was responsible as a proportion of the victim’s total exposure. Accordingly, the claimant could recover only 35.2% of the damages from the defendants.