Fairchild v Glenhaven Funeral Services Ltd

The House of Lords allowed the appeals and held that, in mesothelioma cases where (i) an employee was exposed to asbestos by two or more employers in successive employments, (ii) each employer owed and breached a duty to take reasonable precautions against exposure, (iii) each breach exposed the employee to a risk of mesothelioma and materially increased that risk, and (iv) the available medical science cannot identify on a balance of probabilities which exposure caused the disease, the claimant is entitled to recover against any employer who materially increased the risk. The court treated a defendant's wrongful conduct that made a material increase in the risk of contracting mesothelioma as sufficient to establish the necessary causal connection in the special circumstances described (the five-to-six factor formulation in the reasons).

The decision relied on authority such as Bonnington Castings v Wardlaw and McGhee v National Coal Board, distinguished Wilsher v Essex Area Health Authority, and was justified by principle and policy: it prevents the denial of a remedy where scientific uncertainty makes ordinary "but for" causation unprovable despite the fault of employers who created the risk.

The appeals concerned claims by sufferers (or their estates) of mesothelioma who had worked for more than one employer and who could not, because of the present limits of medical science, prove which particular period of employment caused the disease.

• Nature of claims: personal injury/wrongful death claims in negligence and for breach of statutory duty (including an admitted breach under section 63 of the Factories Act 1961 in one instance). Relief sought was damages from employers who had exposed claimants to asbestos dust.
• Procedural posture: the claimants lost in the High Court and the Court of Appeal ([2002] 1 WLR 1052) on causation grounds and appealed to the House of Lords.
• Issues framed: (i) whether conventional "but for" causation must be relaxed where multiple tortfeasors each materially increased the risk of a disease and medical science cannot attribute the disease to any particular exposure; (ii) whether McGhee v National Coal Board should be treated as authority for treating a material increase in risk as sufficient for causation; (iii) the proper limits of any such exception (distinguishing Wilsher).

The House concluded that where the claimant satisfies the specific factual conditions set out in the reasons — successive exposures by separate employers, each in breach of a duty to guard against the risk of mesothelioma, each exposure materially increasing the risk, the disease being one which medical science cannot trace to a specific exposure, and other non-work causes effectively discounted — the claimant is entitled to recover against any employer who materially increased the risk. The court explained that this approach follows principle and authority (notably Bonnington and McGhee), that it avoids leaving victims uncompensated because of scientific indeterminacy, and that it must be applied with restraint and confined to cases exhibiting those features. The House allowed the appeals and remitted appropriate relief, while noting that defendants may seek contribution among liable employers.

Appeal allowed. The House held that where (1) a claimant was exposed in successive employments to asbestos by two or more employers, (2) each employer owed and breached a duty to protect against the known risk of mesothelioma, (3) each breach materially increased the risk of contracting mesothelioma, (4) the claimant contracted mesothelioma and other causes are ruled out, and (5) medical science cannot identify which exposure caused the disease, then each employer who materially increased the risk is liable. The ordinary "but for" test is therefore varied in these narrowly defined circumstances to avoid injustice caused by scientific indeterminacy.

Claimants lost at first instance and in the Court of Appeal ([2002] 1 WLR 1052). The appeals were allowed by the House of Lords ([2002] UKHL 22) and reasons were given on 20 June 2002.