Good News: PA Supreme Court Rejects the “Any Fiber” Theory of Asbestos Causation

Last week, in a 5-0 decision, the Pennsylvania Supreme Court rejected the theory that each and every fiber of inhaled asbestos is a substantial contributing factor to any asbestos-related disease. 

In the case of Betz v. Pneumo Abex llc., the Plaintiff brought a products liability action against the defendants alleging that throughout her husband’s forty-four year career as an automechanic, his exposure to asbestos-containing friction products, such as brake linings, caused his mesothelioma, a disease that eventually killed him.  The defendants anticipated that the plaintiff would rely on expert opinion that each and every exposure to asbestos, no matter how small, contributed substantially to the development of the asbestos-related disease.  This theory has become known as the “any breath” or “any fiber” theory of legal causation.  The defendants sought to preclude such opinion testimony based on a litany of legal theories, and the trial court subsequently held a Frye expert evidence hearing.

The question that came in front of the Supreme Court was whether or not the trial court’s decision to conduct a Frye expert evidence hearing was appropriate.  The Supreme Court held that Judge Robert Colville, the trial court judge, was rightly guarded about the scientific methodology underlying the “any fiber” opinion.  Furthermore, the court found that the “any fiber” opinion skirts the need for plaintiffs to prove causation by more conventional routes, such as presenting a full occupational history and details of exposure, as well as distinguishing other exposures as possible causes of the disease.

This decision changes the face of asbestos litigation in Pennsylvania and will have a far-reaching positive impact.  Plaintiffs can no longer lump together exposures and say that all the exposures contributed to a disease.  This brings asbestos litigation in line with the mainstream causation requirements for other substances.  Plaintiffs must be able to prove that each product was a substantial factor in causing their disease.