Although people sometimes violate the law, there is more legal compliance than we can explain by ordinary economic theory – that legal sanctions deter noncompliance. In some domains of international law and constitutional law, there is no credible threat of legal sanctions, yet there is compliance. In some historic examples, “courts” lacking any sanctioning power resolved disputes arising in medieval Iceland, among 18th century pirates, and among 19th century gold-rushers. Professor McAdams explains these and other historic and contemporary examples of compliance by focusing attention on law’s expressive power. First, legal expression provides a salient means of coordinating behavior. Second, law reveals information about risks and attitudes. These two expressive powers are distinct from law’s coercive power.

Richard H. McAdams is Bernard D. Meltzer Professor of Law and Aaron Director Research Scholar at the University of Chicago Law School. This talk was recorded on January 6, 2015, as part of the Chicago's Best Ideas lecture series.