On January 6, 2021, hundreds of individuals converged on and breached the U.S. Capitol building in an effort to overturn the presidential election results. For the present study, open-source research was conducted on 101 federally indicted participants of this event—half of whom were indicted on assault or other violent felony crimes and the other half for trespassing or nonviolent misdemeanor charges. Then, we used the Terrorism Radicalization Assessment Protocol (TRAP-18; Meloy & Gill, 2016) to examine these Capitol insurrection participants indicted for their actions. Four proximal warning behaviors and one distal behavior were significantly found to be related to the individuals indicted for violent crimes. Similar to previous work using the TRAP-18, these results indicate that several dimensions of the tool postdicted violent behavior in this sample. Interestingly, this was the first study to test the TRAP-18 validity in a large group of extremists acting in concert.

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Source Publication

Journal of Threat Assessment and Management


Accepted Version

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© 2023 American Psychological Association.


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