Drs. Charles Epp, Steven Maynard-Moody, and Donald Haider-Markel had an article, "Beyond Profiling: The Institutional Sources of Racial Disparities in Policing," published in Public Administration Review.
From their abstract, "American policing faces a crisis of legitimacy. A key source of this crisis is a widespread police practice commonly endorsed by police leaders to fight crime. This is the investigatory stop, used to check out people who seem suspicious and to seize illegal drugs and guns and make arrests. Using data from an original scientific survey of drivers in the Kansas City metropolitan area, the authors show that racial disparities in police stops are concentrated in investigatory vehicle stops. In these stops, but not others, officers disproportionately stop African Americans and question and search them. The overwhelming majority of people stopped in this way are innocent, and the experience causes psychological harm and erodes trust in and cooperation with the police. Many of the most controversial police shootings during the past two years occurred in these stops. Reforming this practice is an essential step toward restoring trust in the police."