The partisanship of mayors has no detectable effect on police spending, police employment, crime, or arrests.

In this paper, we examine whether mayors' partisan affiliations lead to differences in crime and policing. We use a large new dataset on mayoral elections and three different modern causal inference research designs (a regression discontinuity design centered around close elections and two robust difference-in-differences methods) to determine the causal effect of mayoral partisanship on crime, arrests, and racial differences in arrest patterns in medium and large US cities. We find no evidence that mayoral partisanship affects police employment or expenditures, police force or leadership demographics, overall crime rates, or numbers of arrests. At the same time, we find some suggestive evidence that mayoral partisanship may modestly affect the racial composition of arrests. Overall, the results from our multimethod analyses indicate that local partisan politics has little causal impact on crime and policing.