Mesothelioma: Trigger litigation in the Supreme Court

Words can be slippery things. You think they mean one thing; then they are tested against an unusual set of facts and are found to mean something completely different. So public liability insurers, grateful for Bolton Metropolitan Borough Council v Municipal Mutual Insurance Ltd [2007] Lloyd’s Rep IR 173 and the consequent shortening of their public liability tail in asbestos cases, must now be wondering if the wording of their policies is as clear as they thought. In the latest instalment of the so-called ‘Trigger litigation’, Employers’ Liability Policy Trigger Litigation: Durham v BAI (Run Off) Ltd [2012] UKSC 14, the Supreme Court has held that in the employer’s liability context ‘injury sustained’ policy wording responds in mesothelioma cases at the point of exposure of the employee to asbestos fibres. The case is considered by Neil Hext of 4 New Square.

Trigger: the facts

Mesothelioma is a frightening disease. A cancer of the lining of the lung and inevitably fatal, it is thought to be caused in most cases by exposure to asbestos, which usually itself occurs during the course of the victim’s work. The cancer develops as a result of mutations in an individual cell. That cell multiplies, eventually to form a tumour with its own blood supply. It is only at that point, about five years prior to the point of diagnosis, that malignancy is thought to be irreversible. The mutations are believed to be caused by exposure to asbestos fibres. The process itself is not fully understood, but the more fibres that are inhaled, the greater the risk of development of the disease. The problem, from the perspective of the EL policies that were in issue in the Trigger case, is that the period between exposure and the point at which the tumour properly develops is usually 30 to 40 years. Those that are presenting with the disease now were exposed to asbestos in the 1960s and 1970s.