I examine how racial disparities in police use of force vary using new data covering every municipal police department in New Jersey. Along the intensive margin of force severity, I find disparities that disfavor Black subjects and are larger at higher force levels, even after adjusting for incident-level factors and using new techniques to address selection bias. I then extend empirical Bayes methods to estimate department-specific racial disparities and observe significant differences across and within these hundreds of departments. My findings suggest that ignoring heterogeneity in police use of force misrepresents the problem and masks the existence of both departments with very large disparities and those without apparent disparities against Black civilians, but the variation even within departments may make identifying and treating inequitable policing difficult.

中文翻译：

---

警察使用武力的种族差异的变化

我使用涵盖新泽西州每个市警察局的新数据研究了警察使用武力的种族差异如何变化。沿着武力严重程度的密集边缘，我发现差异不利于黑人受试者，并且在较高武力水平下更大，即使在调整事件级别因素并使用新技术来解决选择偏差之后也是如此。然后，我扩展经验贝叶斯方法来估计特定部门的种族差异，并观察这数百个部门之间和内部的显着差异。我的研究结果表明，忽视警察使用武力的异质性会歪曲问题，并掩盖了对黑人平民存在巨大差异的部门和没有明显差异的部门的存在，但即使是部门内部的差异也可能使识别和处理不公平的警务变得困难。