THE PSYCHOLOGY OF PERSUASIVE PRECEDENT

Abstract

Adherence to precedent is a bedrock principle in a common law judicial system. Public support for courts depends upon many factors, including the perception that they are stable institutions that adhere to their own rules. Courts that ignore precedent risk undermining the legitimacy of the judicial system. That said, judges must also have the ability to make independent choices. This article presents an empirical study of the influence of non-binding, or persuasive, precedent on 952 sitting judges. We gave the judges one of four hypothetical cases, each of which contained configurations of persuasive precedent. We found that: (1) judges largely ignored a single non-binding precedent; (2) judges were more likely to make decisions that were consistent with three non-binding precedents; and (3) judges also tended to make decisions consistent with three non-binding precedents, even when they were accompanied by a fourth inconsistent non-binding precedent. Overall, the portrait of judicial reliance on non-binding precedent appears sensible, but less than optimal.