Best to Be Last: Serial Position Effects in Legal Decisions in the Field and in the Lab

Experts in many domains, from education and finances to sports and entertainment, make multiple similar but independent decisions in sequence. Does the mere serial position of a case in a sequence influence the decision? We focus on the legal domain in which many high-stakes decisions are made in a sequence and justice considerations imply irrelevant factors like serial position of a case must not impact decision making. We identify four mechanisms that can drive serial position effects and note each can have different predictions, hence existence and direction of such effects are empirical questions. Indeed, most empirical evidence from non-legal settings suggests decisions become more favorable with serial position, but a previous study of sequences of parole hearings finds the opposite effect. We analyze two field datasets, 386,109 US immigration judges’ decisions on asylum requests and 20,796 jury decisions in 18th century London criminal court, and find decisions become more favorable (lenient) the later a decision is made in a sequence of decisions. To complement the analysis, we run three controlled experiments with laypeople and find similar results. We conclude that while serial position effects may be context-specific, from the point of view of the individual involved, it is often best to be last.