Do Rape Shield Laws Increase Reporting of Sexual Violence? Evidence from a Difference-in-Differences Analysis

• In Event: The Diffusion and Implementation of Criminal Laws I

Abstract

Sexual violence remains a critical issue in the United States: approximately one in four women experiences completed or attempted rape in their lifetime (CDC, 2024). Despite this prevalence, only one-third of sexual assaults are reported to law enforcement (RAINN, 2025), largely due to fear of retraumatization, skepticism about the legal process, and concerns over victim-blaming. In response, beginning in the late 1960s, U.S. states enacted rape shield laws to restrict the admissibility of victims’ past sexual behavior in court. However, the impact of these laws on reporting behavior remains empirically untested. We evaluate the effect of rape shield laws on reported rapes using a difference-in-differences approach. Leveraging Uniform Crime Reports (UCR) data from 1970 to 1979, we compare changes in reported rapes among counties bordering states that adopted rape shield laws in 1975 to those in neighboring states that delayed implementation until after 1979. We hypothesize that earlier enactment led to higher reporting rates. Findings from this study will have direct policy implications: if stronger victim protections increase reporting, legal frameworks should prioritize survivors' rights. Given persistent underreporting, this study provides critical evidence on whether legal reforms can dismantle barriers to reporting sexual violence.

Authors

• Flavia Mandatori, University of Pennsylvania

• Jonah Gelbach, University of California, Berkeley