The Impact of Mass Shootings on Gun Policy

by Michael Luca, Deepak Malhotra, and Christopher Poliquin

Overview — The authors constructed and analyzed a dataset of all United States gun legislation and mass shootings between 1989 and 2014, finding that mass shootings do lead to significant policy responses: Lawmakers introduce 15 percent more bills the year after a shooting, an effect that is 66 times larger than the impact of non-mass shooting gun homicides. When it comes to enacting laws, Republican-controlled legislatures loosen restrictions on guns. Overall, the results suggest that random and infrequent events can be crucial levers for policy consideration. In the context of gun policy, the results highlight the need for a broader approach to solve gun violence.

Author Abstract

There have been dozens of high-profile mass shootings in recent decades. This paper presents three main findings about the impact of mass shootings on gun policy. First, mass shootings evoke large policy responses. A single mass shooting leads to a 15% increase in the number of firearm bills introduced in a state in the year after a mass shooting. Second, mass shootings account for a small portion of all gun deaths but have an outsized influence relative to other homicides. Our estimates suggest that the per-death impact of mass shootings on bills introduced is about 80 times as large as the impact of individual gun homicides on non-mass shooting incidents. Third, when looking at enacted laws, the impact of mass shootings depends on the party in power. A mass shooting increases the number of enacted laws that loosen gun restrictions by 75% in states with Republican-controlled legislatures. We find no significant effect of mass shootings on laws enacted when there is a Democrat-controlled legislature.