Because it maybe happening in your community.
Annie Vartanian (University of Pennsylvania – Department of Criminology) has posted Racial Disparities In Stop and Frisk Distributions by the Philadelphia Police Department on SSRN. Here is the abstract: The rates of police stops of Black and White pedestrians vary greatly in Philadelphia, Pennsylvania. Using a propensity score design, this study matches the rates of stops using stop data characteristics from the Philadelphia Police Department to further analyze racial disparities in police stops. Re-weighting allows to better analyze stop distributions by assessing the difference of frisk rates between Blacks and Whites. The purpose of comparing the stops in similar situations is that if the location of the stop is controlled for, along with the gender, year, and time of day of the stop occurrence, the explainatory variable left to be a plausible reason in stop rate differences between the groups is race. Black pedestrians in Philadelphia are disproportionally frisked more than White pedestrians, 15% vs. 10%. However, Philadelphia police are more likely to recover contraband from frisked Black pedestrians.