Neil Roland, MacDonald John M, Braga Anthony A
Department of Economics, Statistics and Sociology, RAND, Santa Monica, CA, USA.
Department of Criminology, University of Pennsylvania, Philadelphia, PA, USA.
Nat Hum Behav. 2025 Apr 11. doi: 10.1038/s41562-025-02169-7.
The rate of fatal shootings by officers is highly variable across American police agencies, yet the reasons for this variability remain unclear. This study uses Bayesian multilevel models to partition the variation in fatal police shooting rates across 2,727 police agencies between 2015 and 2020 into 3 sources of variability: randomness, differences in social context, and outlier agencies that have exceptionally higher or lower rates than is predicted by observed factors. The results indicate that variation in police shooting rates across agencies is far from random and is primarily associated with differences in social contexts, especially differences in crime rates, 911 call rates, officers per capita and the prevalence of guns. However, even after accounting for extensive differences in contexts, several police agencies consistently have lower or higher police shooting rates than predicted.
美国各警察机构中警察致命枪击事件的发生率差异很大，但这种差异的原因尚不清楚。本研究使用贝叶斯多层次模型，将2015年至2020年间2727个警察机构中警察致命枪击率的差异分为三个变异来源：随机性、社会背景差异以及枪击率异常高于或低于观察因素预测值的异常机构。结果表明，各机构间警察枪击率的差异并非随机，主要与社会背景差异有关，尤其是犯罪率、911报警率、人均警察数量和枪支普及率的差异。然而，即使考虑到背景方面的广泛差异，仍有几个警察机构的警察枪击率持续低于或高于预测值。
