The study’s goal is to examine the multi-level representation in the context of cooperation and support between black police chiefs and street-level officers. Another goal here is to re-examine and propose different critical mass models in policing. The study uses police killing data from 2014 to 2017 in the United States. Using multi-level modeling techniques, the existing critical mass model, which assumes a single threshold, is not supported. Instead, the study finds that the mutual support model is supported, showing that street-level black officers need support from the black chief, while the black chief also needs further support from street-level officers. Simultaneously, it finds that the presence of a black chief shifts the threshold of street-level representation to a lower level, showing a close relationship between mutual support and critical mass due to a similar mechanism. The findings suggest the importance of police leadership.

中文翻译：

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重新审视多层次代表性和临界质量：黑人领导层的作用及其与街头警察在警察杀戮中的关系

该研究的目标是考察黑人警察局长和街头警察之间合作和支持背景下的多层次代表性。这里的另一个目标是重新审视并提出不同的警务临界质量模型。该研究使用了 2014 年至 2017 年美国警察杀人数据。使用多级建模技术，不支持假设单个阈值的现有临界质量模型。相反，研究发现相互支持模型得到了支持，表明街头黑人警官需要黑人酋长的支持，而黑人酋长也需要街头警官的进一步支持。同时，研究发现，黑人酋长的存在将街道代表的门槛降低到了较低水平，由于类似的机制，显示出相互支持和临界群众之间的密切关系。研究结果表明警察领导力的重要性。