The decision to overrule U.S. Supreme Court precedent, we argue, results from the justices’ pursuit of their policy preferences within intra- and extra-Court constraints. Based on a duration analysis of cases decided from the 1946 through 1995 terms, we show that ideological incongruence between a precedent and a subsequent Court increases the chance of it being overruled. Two legal norms also exert substantive effects as the Court is less likely to overrule statutory precedents and more likely to overrule precedents that previously have been interpreted negatively by the Court. While certain precedent characteristics also influence this decision, the political environment exerts no such effect. Consequently, one of the principal implications of this research is that legal norms influence Supreme Court decision making.