Three Concepts of Probabilistic Causation in the Law

Abstract

Frederick Schauer and Barbara Spellman have recently argued that the probabilistic treatment of causality is widespread in legal practice. Although judicial decisions are focused on single events, there are many aspects of the law in which the relationship between cause and effect is interpreted in probabilistic terms. As in social and natural sciences, also in the law what matters is often to predict ex ante the class of consequences flowing from a class of acts, and this kind of predictions govern legal judgments more than we usually believe. The view just outlined captures some important aspects of legal practice, that have been insufficiently explored by the philosophy of law. However, in the paper I elaborate on the points made by Schauer and Spellman and propose some refinements of them. Probabilistic causal statements in the law often presuppose different concepts of probability. In other words, the expression “probabilistic causation” is ambiguous and needs to be clarified. Distinguishing between different concepts of probability may help to evaluate the use of probabilistic causation in legal practice and to better understand its function in legal proceedings.