This paper characterizes the efficient evidentiary thresholds for establishing negligence when courts have imperfect evidence about care. An evidentiary threshold refers to the "weight of evidence", given the risk of error, for ruling that a party was at fault and differs from the substantive...

In an environment where the optimal level of care is unknown, we ask, under a state-of-the-art defense, which method is better able to induce parties to undertake optimal care. Assuming courts can see a noisy signal of research activities undertaken by a defendant and by some of its competitors,...