Deterrence versus Judicial Error: A Comparative View of Standards of Proof

We argue that the common-law standard of proof, given the rules of evidence, does not minimize expected error as usually argued in the legal literature, but may well be efficient from the standpoint of providing maximal incentives for socially desirable behavior. By contrast, civil law's higher but somewhat imprecise standard may be interpreted as reflecting a trade-off between providing incentives and avoiding judicial error per se. In our model, the optimal judicial system has rules resembling those in the common law when providing incentives is paramount. When greater weight is given to avoiding error, the optimal system has civil-law features.