Causation and opportunity in tort

This article shows that we can approach both ‘epistemic’ and ‘conceptual’ problems of causation in tort with the aid of a moral idea sketched out by HLA Hart and developed into a more general account by TM Scanlon. Applied to causation, that idea is that we may justify principles that require people to meet a certain standard of causation and principles that specify a standard of proof for that purpose by appealing to the value for people of the opportunities that the relevant principles make available to them. The idea is developed in the context of epistemic questions, then extended to conceptual ones. The idea explains both why we may apply certain familiar standards of causation in easy cases, and why and how far we ought to relax or modify those standards in hard cases.