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Prison and Violent Political Extremism in the United States

NCJ Number
Journal of Quantitative Criminology Volume: 36 Dated: 2020 Pages: 473–498
Date Published
26 pages

This study considered the link between imprisonment and post-prison participation in violent political extremism.



The three research questions addressed were (1) whether spending time in prison increases the post-release risk of engaging in violent acts; (2) whether political extremists who were radicalized in prison are more likely to commit violent acts than political extremists radicalized elsewhere; and (3) whether individuals who were in prison and radicalized there were more likely to engage in post-prison violent extremism compared to individuals who were in prison and did not radicalize there. The study conducted a two-stage analysis that first preprocessed the data using a matching technique to approximate a fully blocked experimental design. Using the matched data, researchers then calculated the conditional odds ratio for engaging in violent extremism and estimated average treatment effects (ATE) of the outcomes of interest. Results indicated that the effects of imprisonment and prison radicalization increased post-prison violent extremism by 78–187% for the logistic regression analysis, and 24.6–48.53% for the ATE analysis. Both analyses show that when radicalization occurs in the context of prison, the criminogenic effect of imprisonment is doubled. Supporting longstanding arguments that prison plays a major role in the identity and behavior of individuals after their release, the current study found consistent evidence that the post-prison use of politically motivated violence can be estimated in part by whether perpetrators spent time in prison and whether they were radicalized there. (Publisher Abstract)


Date Published: January 1, 2020