By Rachel A. Kane; Basia E. Lopez; Paul A. Haskins

This Special Report of the National Institute of Justice (NIJ) presents a synthesis of select findings from over 60 publications on 18 NIJ-supported research projects on public mass shootings, including school mass shootings, since 2014. It also identifies areas of need and interest for future research and recommendations. For the purpose of this report, we define public mass shooting as a shooting event in a public setting that causes at least four fatalities in a single event. Excluded from our definition are events that occur in the course of a separate felony or domestic incident. However, the definition of a mass shooting varies among sources; for more information see “The Challenges of Defining ‘Mass Shooting’” in Part I of this report.

Washington, DC: U.S. Department of Justice Office of Justice Programs National Institute of Justice , 2023. 42p.