Assessing the extent of an employer's liability for damages in personal injuries caused by asbestosis has been clarified. Where an employee suffers injuries as a result of exposure by several employers to a noxious substance, such as asbestosis, is the employer who has made a material contribution to the injury liable for the whole resulting disability? Or is he only liable to the extent of his contribution towards the injury? The commonly held view is that the former is correct.

On April 6 this year, the Court of Appeal provided some welcome clarification to this difficult, and at times unfair, question of material contribution (Holtby v Bingham & Cowan (Hull)). It unanimously decided that the latter approach is correct. There was disagreement, however, regarding the question of on whom the burden of proof lies.

Mr Holtby had spent most of his working life employed as a marine fitter, mostly with Bingham & Cowan, although he had worked for other companies doing similar work. As a result of exposure to asbestos dust throughout his working life, he developed asbestosis, and subsequently brought a claim against Bingham & Cowan.

Damages reduced

The judge at first instance found the defendants only liable for the damage that they had caused. While commenting that quantification was difficult on the evidence, he had reduced the general damages by 25% from £32,000 to £24,000 in view of the other companies' contribution to Mr Holtby's injuries. The Court of Appeal then upheld this approach.

Mr Holtby had argued that all he had to prove was that, if the defendant had made a material contribution to his disease, he was entitled to recover all his loss from that defendant, even if other employers had contributed to his injury. The defendant can seek contributions from the other companies that contributed to the claimant's injuries. The onus, however, is on the defendant to prove that others were responsible for some, and if so, the extent, of the injury.

Giving the lead judgment, Stuart Smith LJ rejected Mr Holtby's arguments. He pointed out that the issue had never been fully debated by the House of Lords in the two cases traditionally relied on by claimants to obtain judgment in full against one defendant (Bonnington Casting v Wardlow 1956 and McGhee v International Coal Board 1973). Stuart Smith LJ observed that in both cases the defendants had argued simply that they were not liable, and had never sought to claim that others may have been liable for, or have contributed to, the claimant's condition.

Stuart Smith LJ also decided that the onus of proving causation stays with the claimant; not the defendant. He said the claimant will succeed if he can prove the defendant made a material contribution, but only to the extent of that contribution. If the defendant does not raise or argue the point that others may be liable, however, the claimant may succeed in full.


Clark LJ agreed that the defendant is liable for the contribution that its negligence or breach of statutory duty made to the claimant's condition. However, he expressly disagreed on the burden of proof. He accepted that the burden of proving that the defendant caused the injury is on the claimant. But he said that the claimant discharges that burden by proving the defendant's conduct made a material contribution and he is entitled to judgment in full, unless the defendant proves that a definable part of his condition was caused either by "innocent" exposure or by "guilty" exposure caused by others.

In the Holtby case, evidence established that others had contributed to the disease. The Holtby case is therefore crucially important, not only for cases where more than one party contributed to the condition and there is evidence to support this, but also where there was "innocent" exposure which has materially contributed to the condition and evidence to support it.

In short, whilst there may be some debate on the burden of proof, in practice if the defendant has evidence that others caused or contributed to the claimant's condition, or that there was "innocent" exposure, this should be raised in the defence and evidence produced to support it. The requisite date of knowledge takes on an even greater significance, particularly in deciding whether there should be any reduction in the final award of damages.

From a practical point of view, the lesson seems to be: don't risk being caught out – plead the point in the defence. The claimant will thus be aware at an early stage and, at the very least, it may encourage the claimant to include the other relevant parties, thereby making apportionment or settlement easier.

  • Philip Tracey is an insurance litigation partner with national law firm Beachcroft Wansbroughs