Law, science and uncertainty litigation issues.

• Author: McAdams, Alison

Writing in the October issue of the newsletter of the Toxic and Hazardous Substances Litigation Committee, Alison McAdams and Fiona Gill, litigation partners in Davies Arnold Cooper, London, discuss complex products:

Success in product liability personal injury actions is dependent on the claimants establishing a cause-and-effect relationship between the alleged harmful product and the damage that is said to have resulted. Where a product is dependent on the latest innovations in science or medicine, a court faced with a dispute is unlikely to find any simple answers.

Claimants frequently find it difficult to establish the necessary chain of causation in product liability claims, particularly those which focus on embryonic science. The burden of proof is on the claimant, at least in the United Kingdom, and therefore hard scientific facts, or at least a strong consensus of expert opinion, is necessary to win.

These difficulties were recently illustrated in the oral contraceptive litigation, XYZ v. Schering Healthcare, [2002] EWH 1420, in which a group of 99 women lost their claim that the third generation oral contraceptive pills carried an increased risk of injury. The three-month hearing in the High Court involved evidence from 10 epidemiologists. The court had to decide whether COC3s carried a true excess risk of more than twice that of COC2s. It eventually found that they did not.

A turning point

A recent House of Lords decision in a mesothelioma claim, however, could prove a turning point for claimants in future group actions involving an element of scientific uncertainty. In Fairchild v. Glenhaven Funeral Services Ltd., [2002] UKHL 22, the Law Lords delivered a new interpretation of the legal rules on causation to allow claimants in a number of linked cases to succeed.

Asbestos-related disease, in particular the deadly cancer mesothelioma, usually has a long latency period. For mesothelioma, this can be up to 40 years. A claimant may have worked for a number of different employers during this time and have been exposed to asbestos fibres at any number of locations. In the case of mesothelioma, medical experts agree that very modest exposure can trigger the disease.

Historically, defendants and their insurers have settled this type of claim on a time exposure basis, and damages have been paid according to that apportionment.

In Fairchild, the defendant insurers successfully argued, at first instance and in the Court of Appeal, that because the claimant could not, on the balance of probabilities, demonstrate which...