In the U.S. criminal legal system, jurors are told they must be sure “beyond a reasonable doubt” before convicting someone of a crime. This high standard exists to help prevent wrongful convictions. As the 18th-century jurist Sir William Blackstone famously said, “It is better that ten guilty persons escape than that one innocent suffer.”
But research shows that many jurors don’t fully understand this standard or struggle to apply it consistently. One reason may lie in something called “error aversion” — the idea that people are more afraid of making one type of mistake over another. For example, some people may be more concerned about letting a guilty person go free than about convicting someone who might be innocent.

Our project explores how these error aversions influence people’s decisions in the criminal legal system — not just in the jury box, but also in choices like whether to call the police or identify a suspect. We aim to uncover what drives these instincts, how they affect justice, and whether we can design better tools or messages to help people weigh fairness and safety more thoughtfully. We’ll also work directly with judges, attorneys, and law enforcement to share insights and support more informed decision-making across the system.