Fairchild v Glenhaven Funeral Services Ltd
Pendleton v Stone & Webster Engineering Ltd
House of Lords
Citations:  UKHL 22;  1 AC 32;  3 WLR 89;  3 All ER 305;  ICR 798;  IRLR 533;  PIQR P28.
The claimants were all employees who developed mesothelioma as a result of asbestos exposure. In each case, the claimant was negligently exposed to asbestos by multiple employers. At the time, doctors believed that any single fibre of asbestos (or a small number) could cause mesothelioma. For this reason, there was no way of proving which employers’ negligence was responsible for the claimants’ illnesses. This meant that the claimant could not prove that but for the negligence of any particular employer they would not have suffered their injury.
- Could the claimants prove that any particular employers’ negligence caused their injury?
The House of Lords held in favour of the claimants. Each employer had materially contributed to the risk of them contracting mesothelioma. This was enough to establish causation in this kind of case.
This Case is Authority For…
Where the claimant suffers a disease whose onset cannot be attributed to any particular or cumulative negligent event, the court will apply a different test of causation. All the claimant must prove is that the defendant materially increased the risk of the claimant suffering the injury.
Lord Nicholls stressed that the court is not using the ‘material contribution’ test to infer that ‘but for’ causation is satisfied. He acknowledged that it is a separate, less stringent test for causation.
Both Lords Bingham, Rodger and Hoffman disapproved of Lord Wilberforce’s judgement in McGhee v National Coal Board  1 WLR 1. In that case, Lord Wilberforce stated that the effect of the material contribution test was to reverse the burden of proof. This would require the employer to prove that they did not cause the injury. Lord Hoffman stated that this made no sense, since the defining feature of these cases is that proof either way is impossible. As such, satisfying the material contribution test is enough to irrefutably prove causation.
Lord Bingham noted that there is no universal test of causation, and that ‘it would seem to me contrary to principle to insist on application of a rule which appeared…to yield unfair results.’ Lord Hoffman agreed that:
‘There is no scientific or philosophical touchstone for determining the relevant causal connection in any particular case. The relevance of a causal connection depends upon the purpose of the inquiry.’
The problem which the House of Lords identified with the ‘but for’ test in this kind of case is that it would essentially render the employer’s duty unenforceable: on the state of scientific knowledge causation can never be proven. This justified an exception to the usual rule of causation.
The Lords differed on how to distinguish the case of Wilsher v Essex Area Health Authority  AC 1074.
- Lord Bingham argued that that case was distinct because there were several different types of ‘noxious agent’ which could have caused the injury. He thought that the ‘material contribution’ exception should only apply to cases where there is only one type of cause.
- Lord Rodger largely agreed with Lord Bingham, but thought that the material contribution rule might still apply in cases where different harmful agents if those agents ‘operated in substantially the same way’.
- Lord Hoffman disagreed, arguing that this is not a principled distinction. He distinguished Wilsher by arguing that the material contribution test only applies where a modified approach to causation is necessary to avoid a duty being effectively unenforceable. This was not the case in Wilsher.