Here the paper, coauthored with Jeff Fagan and Alex Kiss, which will appear in the Journal of the American Statistical Association (see earlier entry). We analyzed data from 15 months of street stops by NYC police in the late 1990s. The short version:
– Blacks (African-Americans) and hispanics (Latinos) were stopped more than whites (European-Americans) in comparison to the prevalence of each group in the population.
– The claim has been made that these differences merely reflect differences in crime rates between these groups, but there was still a disparity when instead the comparison was made to the number of each group arrested in the previous year.
– The claim has been made that these differences are merely geographic–that police make more stops of everyone in high-crime areas–but the disparity remained (actually, increased) when the analysis also controlled for the precinct of the arrest.
In the years since this study was conducted, an extensive monitoring system was put into place that would accomplish two goals. First, procedures were developed and implemented that permitted monitoring of officers’ compliance with the mandates of the NYPD Patrol Guide for accurate and comprehensive recording of all police stops. Second, the new forms were entered into databases that would permit continuous monitoring of the racial proportionality of stops and their outcomes (frisks, arrests).