RELATIVE RISK GREATER THAN TWO IN PROOF OF CAUSATION IN TOXIC TORT LITIGATION

Abstract

The concept of relative risk has been of increasing interest in establishing causation in toxic tort suits. Specifically, courts are asking whether epidemiological data demonstrating a relative risk greater than 2 is required to meet the standard for proof (more likely than not) or to admit an expert's opinion of causation in toxic tort cases. This article analyzes 31 such cases. Although the frequency of judicial opinions referring to relative risk greater than 2 is increasing, courts disagree as to the use of 2 as a bright-line test. These cases also provide information about judicial understanding of epidemiology and toxicology in providing a scientific basis for legal decisions.