More than 60,000 people are victimized by gun violence each year in the United States. A large share of victims cluster in bounded and identifiable social networks. Despite a growing number of violence reduction programmes that leverage networks to broaden programmatic effects, there is little evidence that reductions in victimization are achieved through spillover effects on the peers of participants. This study estimates the direct and spillover effects of a gun violence field intervention in Chicago. Using a quasi-experimental design, we test whether a desistance-based programme reduced gunshot victimization among 2,349 participants. The study uses co-arrest network data to further test spillover effects on 6,132 non-participants. Direct effects were associated with a 3.2-percentage point reduction in victimization among seeds over two years, while potential spillover was associated with a 1.5-percentage point reduction among peers. Findings suggest that peer influence and the structure of networks might be leveraged to amplify gun violence reduction efforts.
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The original data used in this study were provided to the corresponding author as part of a data-sharing agreement with the City of Chicago and the Chicago Police Department, and are prohibited from being shared directly. De-identified replication data generated and analysed in this study are available from the corresponding author upon request.
All analyses were carried out in R. Code for reproducing the results of this study is available from the corresponding author upon request.
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This research was supported by a CAREER award (No. SES-1151449) from the Sociology and Law and Social Science Programs at the National Science Foundation. We thank Y. Charette and D. Kirk for providing valuable feedback. The funder had no role in the conceptualization, design, data collection, analysis, decision to publish or preparation of the manuscript.
The authors declare no competing interests.
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Wood, G., Papachristos, A.V. Reducing gunshot victimization in high-risk social networks through direct and spillover effects. Nat Hum Behav 3, 1164–1170 (2019). https://doi.org/10.1038/s41562-019-0688-1