Journal of Housing Economics (2021) with Vincent Reina.

Working Papers

Abstract: In an effort to thwart crimes in progress and deter future incidents, police in the US conduct millions of civilian street stops each year. Though this practice is commonplace in most large urban police departments, little is known about the net impact of this strategy on crime. This paper exploits the naturally-occurring movement of New York Police Department commanders during the height of New York City's Stop and Frisk program to estimate commanders' effects on civilian stops and their subsequent impact on crime. We generate predictions of commanders' effects on stops in a precinct, conditional on neighborhood demographics, crime rates, and policing strategies. Commanders' effectsestimated using data only from tenures in prior precinctsare highly predictive of observed stops in new precincts, highlighting the transferability of commanders' tactical preference for stops. We find that a high-stop strategy decreases misdemeanor crime within a precinct, but has no effect on more serious felony offenses. Moreover, we find suggestive evidence that the decrease in misdemeanor offenses is partially offset by crime displacement to adjacent neighborhoods. We conclude by demonstrating that commanders may trade off their ability to build police legitimacy in the community with their preference for stops, and that the former strategy is more effective at reducing felony incidents. Contrary to broken windows theory, our findings suggest that stop-and-frisk tactics do not deter more serious criminal behavior, and thus, police should consider alternatives to strategies that emphasize the proactive enforcement of low-level offenses.  

Media Coverage: The New York Times, Chalkbeat

Abstract: Millions of Americansparticularly young men of colorare stopped on the street by police each year. This form of proactive policing has been embraced by cities across the country as a way to maintain order in high-crime neighborhoods and deter more serious crimes before they occur. However, civilian stops rarely lead to an arrest and little is known about the social impacts of frequent, unproductive interactions with police. In this paper, we leverage the quasi-random movement of commanding officers across New York City precincts to estimate the net impact of stop and frisk policing on students' long-run educational attainment. Overall, we find exposure to police stops lowers high school graduation, college enrollment, and college persistence. The negative effects are largest for black students, who are most likely to be directly affected by police stops. However, we also find evidence of increases in overall school safety and positive effects for white and Asian students, highlighting positive spillovers for the students least likely to be targeted. These results highlight the social impacts of criminal justice policy and have important implications for inequality.

Police or Community Bias? Predictors of Black-White Differences in Police Use of Lethal Force (with Andrew Bacher-Hicks and Mark Chin)

On the Road Again: The Effects of Yearly Street Maintenance on Citizen Engagement