Randomization in Adjudication

Adam M. Samaha, University of Chicago Law School

Abstract

This article investigates randomization as a decision rule in adjudicative institutions. It begins by identifying different concepts of randomization and overlapping justifications for its use in social decisions. The article then evaluates the judicial position on randomization. Judges publicly punish other judges for overtly randomizing merits decisions. Yet judges tend to tolerate or even encourage deliberate randomization in nonjudicial institutions, in situations ranging from housing lotteries to military drafts. And judges now embrace randomization when they decide how to assign incoming cases to each other. This last commitment creates particular tension within the system. Given substantial differences in competence and ideology among judges — differences that the new wave of empirical legal studies is confirming — randomizing case assignments will effectively randomize merits outcomes in some cases. The article then offers a defense for this awkward combination of positions. It defends merits randomization bans as crude yet understandable self-restraints adopted by fallible judges with public relations problems. And it defends assignment randomization from several outsider perspectives: as a lottery among litigants with equal claims to the tragically scarce resource of judicial excellence, as a method for honoring outcomes in the judicial appointments process, and as a natural experiment on the elusive determinants of judicial behavior. These arguments cannot fully explain why adjudicative institutions developed as they did. But they can exploit benefits that the system’s designers produced, in a sense, randomly.