Article

Do the Ages of Mass Shooters Matter? Analyzing the Differences Between Young and Older Offenders

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Abstract

As the threat of public mass shootings continues to be on the forefront of Americans’ minds, it begs the question whether there are differences between young and older mass shooters. In general, earlier research suggests that young people are more likely than their older counterparts to commit crimes because of immaturity, lack of impulse control, rebelliousness, peer pressure, poor role models, and the influence of what they see on television or consume through other media content. When it comes to mass shooters, however, the answer to this question may depend on whether ‘‘young’’ offenders are defined using the legal age of adulthood or the scientific definition of when brain development typically reaches maturity. This study aims to determine whether significant differences exist between public mass shooters who were younger than or older than 18 years when they attacked, or younger than or older than 25 years when they attacked, by examining 88 offenders who struck in the United States from January 1982 to March 2018. Tests of statistical significance suggest that with both definitions, young mass shooters are more likely than older mass shooters to obtain their weapons illegally, attack at schools, have a reported history of animal abuse, and admit copying or being inspired by previous attackers. These results are interpreted in the context of previous scholarship, and recommendations are provided for future research.

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