Spatial Epidemiology of Police Use of Force: Identifying Geographic Patterns and Correlates in Seattle

Abstract

Despite growing evidence of social and racial disparities in policing outcomes, relatively little is known about the geographic distribution of police use of force (UOF) within cities or the neighborhood characteristics associated with elevated UOF rates. This study examined the spatial distribution of police UOF across Seattle census tracts and assessed the association between neighborhood socioeconomic disadvantage and UOF rates. Police UOF incident data from the Seattle Police Department covered 177 Seattle census tracts for the years 2020-2024. Census tract-level demographic and socioeconomic data came from the American Community Survey and the City of Seattle Race and Social Equity Index. We assessed spatial clustering using Global Moran’s I, Local Indicators of Spatial Association (LISA), and Getis-Ord Gi* hotspot analysis. We estimated associations between neighborhood socioeconomic disadvantage and UOF rates using Poisson quasi-likelihood regression models with robust standard errors and a log population offset. We assessed residual spatial autocorrelation using Moran’s I, and conducted a post hoc spatial lag model to examine spatial dependence. Police UOF rates demonstrated significant positive spatial autocorrelation across Seattle census tracts (Moran’s I = 0.31, p < 0.001), with hotspots concentrated in central and southern Seattle. In fully adjusted regression models, greater neighborhood socioeconomic disadvantage was associated with higher UOF rates (IRR = 1.15, 95% CI: 1.00, 1.31). Significant spatial autocorrelation remained in the model residuals (Moran’s I = 0.259, p < 0.001), suggesting the presence of additional spatially structured factors. In a post hoc spatial lag model, the association between socioeconomic disadvantage and UOF attenuated (IRR = 1.04, 95% CI: 0.91, 1.17), while neighboring tract UOF rates were positively associated with local UOF rates (IRR = 1.03 per 10-unit increase, 95% CI: 1.02, 1.04).