Although the concept of precedent is basic to the operation of the legal system, there has not yet been a full-length empirical study of why U.S. Supreme Court justices have chosen to alter precedent. This book attempts to fill that gap by analyzing those decisions of the Vinson, Warren, and Burger courts, as well as the first six terms of the Rehnquist Court--a span of forty-seven years (1946-1992)--that formally altered precedent. The authors summarize previous studies of precedent and the Court, assess the conference voting of justices, and compile a list of overruling and overruled cases.