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Lessons Learned on the Methodological Challenges in Studying Rare Violent Incidents

NCJ Number
Date Published
May 2024

This publication summarizes a National Institute of Justice–sponsored convention about rare mass murder incidents.


This article summarizes discussions held at a meeting of grantees and research scholars convened in 2019 by the National Institute of Justice (NIJ) focusing on rare mass murder incidents. The publication also discusses NIJ’s efforts on studying rare violent incidents. The convention participants discussed methodologies, the nuances of collecting and analyzing data on these incidents, and challenges related to validity and accuracy. It closes with implications for the research community and the criminal justice field to consider. As the scientific research, development, and evaluation arm of the U.S. Department of Justice, the NIJ has played a crucial role in improving the knowledge and understanding of rare violent incidents, such as public mass shootings and terrorist events. The Institute has funded various studies over the years that seek to provide rigorous data, a better understanding of what the data convey, improved connectivity between data sources, and consistent definitions so that the field has more information about who perpetrates mass violence, their motivations, and how they plan and carry out their attack.

Date Published: May 1, 2024