Misdemeanor Prosecution.

This article examines the causal effects of prosecuting versus not prosecuting nonviolent misdemeanor offenses on defendants' subsequent criminal justice involvement, using data from the Suffolk County District Attorney’s Office (SCDAO) in Massachusetts. Leveraging the as-if random assignment of cases to assistant district attorneys (ADAs) with varying prosecution leniency, the study finds that nonprosecution of marginal defendants reduces the likelihood of new criminal complaints by 53% and the number of new complaints by 60% within two years postarraignment, with the largest effects among defendants without prior criminal records. The findings suggest that acquiring a criminal record of misdemeanor charges, rather than case disruption or conviction, drives increased recidivism, and that policies increasing nonprosecution rates—such as the 2019 presumption of nonprosecution policy implemented by the newly elected district attorney—are associated with reductions in subsequent criminal complaints without evidence of increased crime. These results highlight the potential public safety benefits of prosecutorial leniency in nonviolent misdemeanor cases and contribute empirical evidence relevant to ongoing policy debates about misdemeanor prosecution practices.