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Pre-Attack Warning Behaviors of 20 Adolescent School Shooters: A Case Study Analysis

NCJ Number
Crime & Delinquency Volume: 68 Issue: 5 Dated: 2022 Pages: 786-813
Date Published
28 pages

This study examined the pre-attack warning behaviors of adolescent school shooters in the United States.


A total of 20 case studies were conducted of adolescent school shooters in the United States who committed non-fatal or fatal shootings on K-12 school grounds between 1999 and 2016. The study examined whether the school shooters displayed warning behaviors before the attack, who in the perpetrator’s life was aware of these warning behaviors, and what, if any, actions were taken in response. Given the emergence of online forms of communication, the study also investigated how adolescent school shooters may variably communicate warning behaviors in online and offline contexts. (publisher abstract modified)



Date Published: January 1, 2022