This article examines the criterion of comparative causation according to which an accident loss is apportioned between a faultless tortfeasor and an innocent victim on the basis of their relative causal contributions to the loss. To explain the rule's structural features, we consider a scenario where liability is allocated on the basis of causation, regardless of fault. While this model brings to light several interesting features, it also unveils the limits of such a criterion with respect to induced activity and care levels. Next we extend the model to consider the comparative causation rule in conjunction with negligence rules. Applying the comparative causation rule under a negligence regime induces a combination of incentives that is not provided by any known liability rule. Copyright 2004, Oxford University Press.
