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“Trigger” Judgment

Mr Justice Burton today delivered his long-awaited judgment in the Employers’ Liability Trigger Litigation. The litigation followed the decision of a number of UK insurers to refuse to pay mesothelioma claims on the traditional “exposure” basis.

Mesothelioma is the generic term for malignant tumours arising in the mesothelial tissue which lines the pleura of the lung. It has been the subject of considerable litigation in the UK over the last few years.

This move was prompted by the Court of Appeal’s decision in Bolton v MMI & CU [2006] 1 WLR 1492, where it was held that (in relation to public liability policies) “injury” in mesothelioma did not occur upon inhalation or exposure but instead when the tumour later developed and/or upon manifestation of symptoms. The tumour developed unknown in the body a number of years prior to manifestation.

The Employers’ Liability (EL) policies operated by the lead insurers were triggered only when injury was “sustained” or a disease “contracted“. Insurers argued that this meant that they responded in EL claims on the same basis as in Bolton. The Claimants argued that injury was a continuous process and occurred at inhalation / exposure- alternatively that these historic EL policies should be read so that “sustained” or “contracted” essentially meant “caused”. This would result in the policies responding on the traditional exposure basis.

There were 6 lead cases involving BAI, Independent Insurance, Excess Insurance and MMI who seeking to apply Bolton to EL policies. The claimants included the families of individuals who had contracted mesothelioma, a number of corporate employers, a group of 10 local authorities and Zurich Insurance. David Platt and Peter Houghton from Crown Office Chambers represented Excess Insurance. A John Williams of Crown Office Chambers represented the local authorities. The key points of the judgment were:

  • That EL policies should be interpreted so that injury “sustained” or “contracted” was to be read in the same way as “caused”. Accordingly the policies would respond on the inhalation/exposure basis. The claimants were therefore successful on the central question in the litigation.
  • That EL policies should not be construed in the same manner as PL policies. Bolton does not therefore apply to EL policies.
  • That injury did not occur at inhalation / exposure but at a later stage when the tumour could be said to have properly developed and gained self-sufficiency. The insurers were accordingly successful on this part of the litigation.
  • That the stage at which the tumour had developed so that “injury” could be said to have occurred was at “angiogenesis”. Angiogenesis was the stage at which a tumour acquired a blood and/or nutrient supply and was unlikely to regress. Angiogenesis generally occurred about 5 years prior to diagnosis. The medical evidence in Bolton was therefore not followed.

The judgment has also interesting observations on the general effect of the Employers’ Liability (Compulsory Insurance) Act 1969, on whether the risk of the development of mesothelioma can be treated as “damage” or injury” for the purposes of a cause of action, and on custom and usage in the EL market.

Burton J granted permission to appeal with a recommendation that the appeal be expedited. The matter will therefore be considered by the Court of Appeal in due course.

The position with existing claims which have been stayed as a result of the Practice Direction which selected the lead cases (and managed the Trigger Litigation) is that the Practice Direction is to be extended until conclusion of the appeal with liberty to apply. Hence the general stay is likely to remain in force.

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