Sociologist Joscha Legewie will use a quasi-experimental research design from a real-world setting to address this question and study when, where, and what kind of events trigger periods of increased racial bias in police stops of pedestrians. Between 2006 and 2012, the New York Police Department stopped, questioned and frisked 3.9 million citizens. Over the same period, many local events, such as four tragic murders of police officers, or homicides more generally, might have influenced the racial bias in police stops. Preliminary findings showed that a fatal shooting of a police officer in December 2012 increased the use of force against Blacks in search and frisk operations by 18.4 percent in the three days after the shootings.
Legewie will compare similar stops before and right after the events to estimate their effect on racial profiling and the use of physical force by police officers. The matched stops will then be used as the counterfactual trend, which captures what would have happened in the absence of the events. The independent variables used in the matching procedure and the regression analyses are the police precinct, the geographical location of the stop in terms of the x and y coordinates on the U.S. Plane Coordinate Systems for New York, the day time of the stop translated to x and y coordinates on a clock circle, and the race, gender, age, and height of the stopped person. The exogenous events will allow the PI to identify the causal effect of local events on racial profiling in pedestrian stops and study when, where, and what kind of events influence racial bias in police stops.