Unnecessary Causes

This article argues that private law, specifically tort law, should adopt a notion of a �cause� that is wider than the relation of necessity that is encapsulated in the traditional but-for test. The law may have an interest in the relation between an indivisible injury and a specific tortious contribution to the mechanism by which it occurred, which contribution was unnecessary because the relevant element of that mechanism was �over-subscribed�. The suggested approach facilitates separation of two distinct issues: whether a breach of duty contributed to the occurrence of the injury of which complaint is made (the �factual cause� issue); and whether that injury represents �damage� relative to the benchmark of where the victim would have been had he not been the victim of tortious conduct.