Lower courts in the United States are generally responsive to specific precedents and trends in the decisionmaking of their judicial superiors. In this article, we ask why. We test one popular explanation—that compliance can be attributed to judges' fear of having their decisions reversed—through an analysis of search and seizure cases decided in the U.S. Courts of Appeals between 1961 and 1990. Since the Supreme Court cannot reverse a decision unless it agrees to review it, we ask whether circuit judges are more likely to decide as the Supreme Court would be expected to when they face cases that are otherwise more likely to be reviewed by the Court. Finding that they are not, we conclude that fear of reversal cannot account for widespread circuit court compliance in these cases, nor, presumably, more generally. More broadly, our findings point to the importance of factors apart from supervisors and the threat of sanctions in determining subordinates' compliance.