How does ethnic politics affect the state’s ability to provide policing services? Using a panel of administrative personnel data on the full careers of 6,784 police officers, we show how the rise of ethnic politics around Kenya’s independence influenced policemen’s behavior. We find a significant deterioration in discipline after Kenya’s first multiparty election for those police officers of ethnic groups associated with the ruling party. These effects are driven by a behavioral change among these policemen. We find no evidence of favoritism within the police. Instead, our results are consistent with co-ethnic officers experiencing an emboldenment effect. Our findings highlight that the state’s security apparatus, at its most granular level, is not insulated from ethnic politics. (JEL D72, J15, K42, O15, O17)