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Communication of Intent to Do Harm Preceding Mass Public Shootings in the United States, 1966 to 2019

NCJ Number
307496
Journal
JAMA Network Open Volume: 4 Issue: 11 Dated: 2021
Author(s)
Jillian Peterson; Gina Erickson; Kyle Knapp; James Densley
Date Published
2021
Length
9 pages
Annotation

This study examines the factors associated with a mass shooting perpetrator’s decision to communicate their intent to do harm and finds that leakage is a critical moment for mental health intervention to prevent gun violence.

Abstract

This cross-sectional study examining the factors associated with a mass shooting perpetrator’s decision to communicate their intent to do harm found that nearly half leaked their plans and that leakage was associated with receiving counseling and suicidality, suggesting it may be best characterized as a cry for help from perpetrators prior to their act. These findings suggest that leakage is a critical moment for mental health intervention to prevent gun violence. Understanding the motivation of a mass shooter’s intent to do harm can help practitioners and policy makers develop more effective intervention strategies. To examine the prevalence of communication of intent to do harm, known as leakage, in a sample of 170 mass public shooters from 1966 to 2019; the characteristics of perpetrators who do and do not leak their plans; and whether leakage is a form of fame-seeking behavior or a cry for help among individuals who are in crisis or suicidal. This cross-sectional study included perpetrators who killed 4 or more people in a public space from 1996 to 2019 and were included in a comprehensive database of US mass shootings. Logistic regression models were used to examine the risk factors associated with leakage. Models estimating leakage were examined to assess the 2 hypothesized pathways to leakage (the cry-for-help model and the fame-seeking model). The 170 participants in this sample included 166 (97.7%) male perpetrators and 3 (2.3%) female perpetrators, with a mean (SD) age of 34 (12) years. Overall, 161 participants had known race and ethnicity: 11 (6.8%) Asian individuals, 35 (21.7%) Black individuals, 14 (8.7%) Latinx individuals, 7 (4.4%) Middle Eastern individuals, 3 (1.9%) Native American individuals, 89 (55.3%) White individuals, and 2 (1.2%) individuals with other race and ethnicity. (Published Abstract Provided)