Driving while black: Bias processes and racial disparity in police stops

We estimate the degree of racial disparity in police vehicular stops separately for local and state police in North Carolina in the year 2000. We introduce four mechanisms that might produce racial disparities in police stops-racial profiling, race sensitive police deployment, cognitive bias and stereotyping, and prejudice. We then model the relative odds of police vehicle stops as a function of race, driving behavior, and other demographic statuses separately by police organization type, with controls for omitted variable bias at both the driver and spatial level. We find only weak evidence of racial disparity in stops by officers of the state highway patrol but stronger evidence in those made by local police officers.