：作为提高执法和问责效率的一种手段，美国警务大数据推动警务实践从传统执法活动向现代情报活动转变，但其在多大程度上改善了警务实践效果仍是一个开放的经验问题。文章探讨了数据驱动警务实践的历史沿革，并从兴起背景、数据特征、技术工具以及现实应用等方面阐述了美国警务大数据的实践进展，考察了美国警务大数据实践中的四个风险议题，并从数据质量控制、数据安全管理与数据分析技术三方面阐述了其带来的政策启示。

As a means of improving the efficiency of law enforcement and accountability, the American police big data promotes the transformation of police practice from traditional law enforcement activities to modern intelligence activities, but to what extent it improves the effectiveness of police practice is still an open empirical issue. This paper discusses the historical evolution of data-driven police practice, and introduces the practical progress of big data in American police from the aspects of its rising background, data characteristics, technical tools and practical applications. The paper examines four risk issues in the practice of American police big data, and then expounds the policy enlightenment from three aspects: data quality control, data safety management and data analysis technology.