Witnesses often gain by slanting testimony. Courts try to elicit the truth with perjury rules. Perjury is not truth-revealing; truth revelation is, however, possible. With a truth-revealing mechanism the judge will get little testimony because the defendant will not present witnesses with...

A safe and risky seller serve a market. While the expensive safe seller can solve the problems of all consumers, the cheap risky seller can help a consumer only with a certain probability. The risky seller's success probabilities are distributed across consumers; by the choice of her quality the...

Physicians choose capacity before demand materializes; actual demand may be higher or lower than capacity. If a physician's capacity exceeds demand, she may have an incentive to overtreat, i.e., she may provide unnecessary treatments to use up idle capacity. By contrast, with excess demand she...

In trials witnesses often slant their testimony in order to advance their own interests. To obtain truthful testimony, the law relies on cross-examination under threat of prosecution for perjury. We show that perjury law is an imperfect truthrevealing mechanism. Moreover, we develop a...