Black drivers in Chicago are more likely to be stopped by police than issued tickets by traffic cameras, highlighting the role of racial bias in traffic stops, according to a new study. The findings, published this month in the Proceedings of the National Academy of Sciences, follow years of scrutiny of racial disparities in Chicago traffic stops.
They also come amid renewed debate about the use of these stops. Outgoing Cook County State’s Attorney Kim Foxx recently unveiled a controversial proposal to decline prosecuting possession cases when guns or drugs are found during traffic stops initiated for reasons like expired registration or a broken light. Officials have also moved to add oversight of traffic stops to a federal consent decree guiding Chicago Police Department reform.
In the latest study, researchers from the University of Illinois at Chicago, Cornell University, Rutgers University and the University of Sydney analyzed GPS data from cellphones and 2019 data on traffic stops and speed camera tickets. They determined the racial makeup of drivers on the road and compared that with the demographics of those stopped or ticketed.
They found that on a street where half of drivers were white, the probability of a white driver getting a traffic camera ticket was just under 50%, while white drivers made up, on average, fewer than 20% of police stops.
The study's authors said automated cameras provided a more race-neutral comparison point. The study refutes arguments that perhaps Black drivers speed more than other drivers, pointing instead to human bias, said Michael Smart, a study author and urban planning and policy professor at Rutgers.
“(Bias is) not just a police issue,” he said. “But it’s especially acute among police because of the powers that police are given.”
