Justice Jay ruled that in multi-defendant asbestos-related lung cancer claims, where no one defendant is responsible for more than half of the total exposure, damages will be apportioned in accordance with each defendant’s relative share of exposure.


The deceased claimant died from asbestos-related lung cancer in January 2013. He was exposed to asbestos by ten employers between 1961 and 1974. Six of these employers were sued by the claimant.

The level of asbestos exposure of the six defendants was quantified at 35.2% of the claimant’s total asbestos exposure; with the individual defendant’s exposure ranging from 2.5% to 10.1%.

Liability was admitted. If the defendants were liable in full, damages totaled GBP 175,000. 35.2% of these damages equaled GBP 61,600.

The issue for the High Court was whether the defendants were liable for damages in full, not at all, or in proportion to their 32.5% share of exposure.


Justice Jay laid down a two-part test in order to determine the extent of the defendants’ liability in multi-defendant cases.

The first stage required the court to consider what caused the cancer on the balance of probabilities. Analysing the claimant’s personal circumstances and the epidemiological evidence, it was found to be more likely than not that asbestos exposure, rather than smoking, had caused the cancer.

The second stage required an assessment of whether it could be proved that the defendants had caused the claimant’s cancer.

The court accepted that where a defendant was responsible for more than half of the total exposure, it would be proved on the balance of probabilities that this exposure had caused the cancer.

However, in the present case, despite all the defendants being negligent, no single defendant was responsible for more than 51% of the exposure. Given the limitations of present scientific knowledge when considering several minority share defendants, it was not possible to infer that any single defendant was responsible for causing the claimant’s cancer. It was found that all that could be inferred was the possibility of that having occurred.

This led the court to extend the application of the Fairchild exception on the basis that mesothelioma and lung cancer are legally indistinguishable conditions. The Fairchild exception (given in Fairchild v Glenhaven Funeral Services Ltd [2003] 1AC 32) provides that defendants whose breaches of their duty of care ‘materially increase the risk’ of mesothelioma [in that case] are liable for the damage suffered if mesothelioma does develop. Following the subsequent case of Barker v Corus UK Ltd [2006] 2 AC 572, damages in such cases should be apportioned in line with the defendants’ contribution to the risk of the claimant contracting the disease.

Accordingly, it was held that the defendants were liable in damages in proportion to their share of the exposure. The claimant was thus limited to recovering GBP 61,600.

Points for Defendants

  • This judgment will have a significant effect on multi-defendant asbestos-related lung cancer practice and in respect of every other type of multi-defendant occupational cancer claims
  • Each defendant is now liable in damages in proportion to its share of the overall exposure. Such diseases are indivisible conditions with divisible consequences; joint and several liability does not apply
  • The case affirms that every exposure to asbestos does not contribute to ‘causation of the lung cancer’ but that each exposure contributes to the ‘risk of contracting the disease’
  • The finding represents a common sense approach by the High Court which is fair to both parties. Had the Fairchild exception not been extended to lung cancer cases, the claimant would not have recovered any damages. Alternatively, if as the claimant argued, it had been found that a material increase in the risk of exposure was the same as a material increase in exposure (and therefore of injury) thus satisfying the causation test, a defendant who was responsible for only 2.5% of the exposure would be required to pay 100% of the damages. Both these outcomes would have been demonstrably unfair