Racial Profiling in Police Stops

An analysis of 100 million police traffic stops has revealed that white people are more likely to be found with illegal items. Despite this fact black and Latino drivers are more likely to be stopped and searched by the police than white drivers.

The Stanford Open Policing Project has gathered data on around 100 million police traffic stops carried out from 2011-2017 across the United States. The data reveals that the police often use racial profiling when deciding which cars to stop. The data scientists at Stanford established a 'veil of darkness' test to explore whether the police are racially profiling drivers. The test looks at the time of day of police traffic stops to determine if black drivers are stopped more often during the hours of darkness rather than during the day. In other words it looked to see if black drivers were stopped more often when police officers could more easily see the race of car drivers. This test revealed that there is a 5 to 10% drop in the number of black drivers stopped by police after sunset, suggesting that the police are racially profiling drivers when using their powers to stop vehicles.

You can view interactive maps showing where drivers were stopped by the police from 2011-2017 on the Stanford Open Policing Project website. These maps provide an overview of police stops in a number of cities across the United States. On each of the maps the race of the car drivers are shown using colored dots. Each map is also accompanied by a local racial dot map which shows you where people live in the city. Each map also includes an option to view one day's data on police stops animated over the course of one day. If you use this feature you can carry out your own 'veil of darkness' test to see if black drivers are stopped more frequently during the hours of daylight than after sunset.

As the name of the project implies the data on police stops from the Stanford Open Policing Project is available under the Open Data Commons Attribution License. The data can be downloaded in both CSV and RDS formats. Shapefiles are also available for a few select locations.