In 2008, 949 law enforcement agencies reported 2,518,825 traffic stops (63 agencies—mostly smaller—didn’t comply). Stops of minority drivers in each community were compared with the total estimated minority driving population for that community. Also compared by race were the reason for stops; the duration of stops; the outcome of stops; the number of “consent searches” (instances where the police ask permission to search a car); and the number of searches resulting in the discovery of contraband.
Based on the data that emerges, it’s clear that African-American, Hispanic, and American Indian drivers are in fact being stopped more than one would expect based on their overall representation in the driving population. But the 2008 study also concludes that inferring from this that there is police bias is “problematic because [it] assume[s] that an officer knows the race of the driver before they make the stop. Very often, particularly at night, and when the vehicles are driving quickly, this is not the case.” As for the reasons for stops—whether for moving violations, equipment problems, or to check license or registration—those tend to be roughly similar across racial lines.
The most significant racial disparity involves consent searches. While the total number of such searches has dropped sharply —by 33 percent—since 2004, they are applied disproportionately: an African-American driver is about three times as likely to be the subject of a search as a Caucasian driver, with a Hispanic driver 2.4 times as likely to be the subject of a search. But when vehicles are searched, whites are more often found to be hiding contraband. Police found contraband 24.37 percent of the time when a white agreed to a search, but just 15.14 percent of the time with a minority driver. This finding is consistent with other studies nationwide.
Some are convinced that this evidence points to a clear pattern of discrimination. As Harvey Grossman, director of the Illinois ACLU asserts, “The five years of data show a pattern of continuing disparate treatment based on race, particularly with consent searches.” In light of this view, when the 2008 report came out, Grossman urged then-Illinois Gov. Rod Blagojevich (remember him?) and Blago’s post-impeachment successor, Gov. Pat Quinn, to ban all consent searches by the Illinois State Police.
Others are less convinced that the data shows bias. Kwame Raoul, who succeeded Obama in the Chicago South Side state senate seat and is a former prosecutor, notes that one explanation for the disparity in consent searches may simply be that “whites are more tuned in to their constitutional rights, so they decline more often.”
And Will Burns, who worked on profiling legislation with Obama and is now a state representative from Chicago, says, “Nobody has a firm idea of how to really quantify if racial profiling exists.” If you have a lily-white town sandwiched between two predominantly black ones, he points out, a relatively higher number of traffic stops of blacks by whites could simply reflect the fact that a higher number of blacks are traveling through the white community rather than any kind of systematic bias.