A variety of theories have emerged that offer plausible explanations, one from the political institutional perspective and others from sociological perspective. There has been renewed interest in the effect of local political structure on police strength in the policing literature. The purpose of this study, therefore, is to assess the two main competing approaches that can explain variation in police employment across cities. The authors used a longitudinal data set collected from the same 280 cities in 1993, 1996, 2000, and 2003. A two-way fixed-effects panel model, used in the statistical analysis, indicates that the political culture approach, which focuses on local government structures, largely fails to contribute to the variation of police strength. The alternative socioeconomic approach better predicts police force levels across U.S. municipal police departments. (Contains 2 tables and 12 notes.)