The connection between racially prejudiced policing and politics has a long history in the United States. In the current period, police organizations have displayed unprecedented support for Republican presidential candidates, and both have organized against social movements focused on addressing racial disparities in police contact. Yet despite strong connections between law enforcement and party politics, we know almost nothing about the relationship between partisan identity and the behavior of police officers. Using millions of traffic stop records from the Florida Highway Patrol and linked voter records, the present study shows that White Republican officers exhibit a larger racial disparity than White Democratic officers in their propensity to search motorists whom they have stopped. This result is robust to an array of alternative empirical tests and holds across varying sociodemographic contexts. I also find that both White Republican and White Democratic officers grew more biased between 2012 and 2020, a period characterized by the rise of the Black Lives Matter movement and the election of Donald Trump.
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