We estimate causal peer effects in police misconduct using data from about 35,000 officers and staff from London’s Metropolitan Police Service for the period 2011–2014. We use instrumental variable techniques and exploit the variation in peer misconduct that results when officers switch peer groups. We find that a 10% increase in prior peer misconduct increases an officer’s later misconduct by 8%. As the police are empowered to enforce the law and protect individual liberties, integrity and fairness in policing are essential for establishing and maintaining legitimacy and public consent1,2,3,4,5. Understanding the antecedents of misconduct will help to develop interventions that reduce misconduct.
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The data that support the findings of this study are not publicly available. If you would like to view and reproduce our results, please contact E.G.Q.-T. to organize a supervised visit to our local network.
Analyses were conducted in R 3.4.5 and Stata 13.1. All code is available in the public repository https://github.com/edikaQT/misconduct_peer_effects.
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This work was supported by Economic and Social Research Council grants ES/K002201/1, ES/P008976/1, ES/N018192/1 and Leverhulme Trust grant RP2012-V-022. The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript.
The authors declare no competing interests.
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Quispe-Torreblanca, E.G., Stewart, N. Causal peer effects in police misconduct. Nat Hum Behav 3, 797–807 (2019). https://doi.org/10.1038/s41562-019-0612-8