The Deceased died of lung cancer as a result of occupational asbestos exposure with several employers, including the six Defendants. It was agreed that the Defendants were responsible for 35.2% of his overall exposure and their respective exposures were also agreed, ranging from 2.5% to 10.1%.
The sole issue for the Court to decide was whether each Defendant was liable for damages in full, or for a portion thereof. This had not been the subject of previous authority.
The medical evidence
The evidence of the Claimant’s medical expert, Dr Rudd, was that where the exposure attributable to each employer is above de minimis levels, it may be inferred that each employer has materially contributed to the causation of lung cancer. In his view, it was highly likely that some of the fibres involved in the carcinogenic processes came from each source of exposure, though he accepted that had any of the Defendants’ exposures not occurred the lung cancer would probably still have developed.
The Defendants’ medical expert, Dr Moore-Gillon, contended that the carcinogenic processes were effectively the same in lung cancer and mesothelioma, and it could not be known whether asbestos fibres inhaled from a specific source did in fact contribute to the Deceased’s lung cancer. Causation could only be talked about in terms of probabilities, and in this case all that could be said was that each Defendant had increased the risk of lung cancer.
The Claimant submitted that lung cancer and mesothelioma are materially different in fact and law. In lung cancer cases, medical causation must be proved on the conventional ‘but for’ basis, and in this case causation was made out because the experts agreed that the Deceased’s lung cancer was caused by occupational asbestos exposure. The court was then entitled to infer that any Defendant who had materially contributed to the exposure had materially contributed to the injury. This argument was based on the contention that either Bonnington v Wardlaw  AC 613 applied precisely, or it that applied with minor modifications, which, it was argued, had been developed to deal with mesothelioma cases before the decision in Fairchild v Glenhaven Funeral Services  1 AC 32. There was a middle-ground between Fairchild and Bonnington, which allowed the Claimant to recover against the Defendants in full.
The Defendants argued that establishing causation in a multi-party lung cancer case is a two-stage process. At the first stage, the cause of the cancer is determined by application of the conventional ‘balance of probabilities’ approach, and in this case was shown to be asbestos exposure. The second stage is to determine who caused the cancer. It was submitted that the second stage did not logically derive from the first stage and that in this case it could not be answered by epidemiological evidence. Since no Defendant was responsible for 51% of the overall exposure, either Fairchild and Barker v Corus  2 AC 572 applied so liability must be apportioned, or causation could not be made out against any Defendant and the claim failed altogether. The middle ground the Claimant sought to occupy was illusory.
Jay J accepted the Defendant’s arguments, finding that lung cancer and mesothelioma are legally indistinguishable. Since no Defendant had contributed to the risk of lung cancer by 51%, it could not be inferred that any had materially contributed to the disease process. Since all that could be proved was contribution to risk, either Fairchild applied or the correct outcome was zero recovery. It was held that Fairchild did apply. It was conceded for the purposes of the trial that if Fairchild applied then Barker applied too, so apportionment must follow. The Claimant was therefore only entitled to recover 35.2% of his claim against the Defendants.
The effect of the decision is that in multi-party lung cancer claims, a Claimant must first prove what has caused the injury, and must then prove who has caused it. If no Defendant is responsible for 51% of the risk, damages will be apportioned according to the Defendants’ respective contribution to the exposure. Where a Defendant is responsible for 51% of the risk, they can be recovered against in full.
These principles could be applicable to other comparable cancers, including perhaps bladder cancer caused by occupational exposure to carcinogens.
This decision extends the application of Barker, despite the recent criticism it received from Toulson LJ in IEGL v Zurich  EWCA Civ 39, who described the case as “problematic” and having “not fared well”. The status of Barker was recently considered by the Supreme Court when it heard IEGL v Zurich on appeal, though judgment is yet to be handed down. The outcome will have further significance in light of Heneghan.
The Claimant has been given permission to appeal, and the process is to be expedited due to the poor health of the Deceased’s widow.