Race and policing preoccupied Americans last week. The two shootings by police of black men in Louisiana and Minnesota rightly sparked outrage and protest across the country. Then came the racially motivated attack that killed five police officers during a Black Lives Matter rally in Dallas.
Tensions between police and the African-American community were already high. For example, a June Gallup Poll reported that 67 percent of blacks believe that police treat African Americans less fairly than whites in their community.
Is there any evidence of such biased policing? Unfortunately, yes.
In a new study, "Targeting young men of color by search and arrest during traffic stops," by the University of North Carolina political scientist Frank Baumgartner and his colleagues find clear evidence of extensive police racial profiling. The researchers reached their conclusions by parsing data encompassing more than 18 million traffic stops in North Carolina between 2002 and 2013.
North Carolina was the first state in the nation to mandate police-stop data collection, and since 2002 the North Carolina Department of Justice has gathered information on every traffic stop from law-enforcement agencies throughout the state. The police can assign reasons for a traffic stop to 10 different categories—speeding, safe movement, equipment issues, not having a seat belt buckled, expired registration tags, and so on. In general, the researchers report that while blacks constitute about 22 percent of North Carolina's population, 31 percent of stopped motorists are black. Whites and blacks are about equally likely to receive citations (tickets) for traffic infractions.
The difference in police treatment becomes apparent when looking at search and arrest statistics. Except in the case of driving while drunk, black motorists are much more likely to be searched or arrested than are white motorists.
For all nine categories of traffic stops (checkpoint stops are excluded) considered in the study, 2.61 percent of white drivers are searched, whereas 4.57 percent of black drivers are. In other words, black drivers are 75 percent more likely to be searched than white ones. Similarly, 1.9 percent of whites are arrested, compared to 2.71 percent of blacks—so blacks are 43 percent more likely to be arrested than white ones. And worse yet, the search disparities for black versus white drivers have been growing over time. In 2002, black men were 70 percent more likely to be searched than white men. By 2007, black men were twice as likely to be searched; by 2013, this difference had grown to over 140 percent. The percent difference in the likelihood of arrest between black and white male drivers remained stable at about 60 percent. Interestingly, black and white women of whatever age were about equally likely to be searched, cited, or arrested during traffic stops.
The researchers suggest that there are two possible explanations for the disparities they document: racially differential policing or racially differential possession of contraband. Since searches subject to warrants and incident to arrests are procedurally mandatory, the researchers look chiefly at searches done with consent or based on probable cause. They report that black men are twice as likely as white men to be searched with consent. This suggests that black men are either more willing to give their consent to being searched or that they are asked more often for such consent. In addition, "Probable cause searches skew strongly toward blacks, indicating that officers are much more likely to be suspicious of criminal wrongdoing when interacting with black motorists."
By one definition, probable cause means reasonably reliable information to suspect there is a fair probability that a person has committed a crime, or that a search will reveal contraband or evidence. So how much more suspicious of black male motorists are North Carolina police? Based on probable cause, officers were 125 percent more likely to search black men than white men in 2002. That differential had increased to 250 percent by 2013, despite the fact that police consistently have been more likely to find contraband with white males than with black males. Similar results were found with regard to consent searches of white and black males.
"So the increased reliance on probable cause to search blacks is not associated with more accurate assessments of the likelihood of blacks engaging in criminal behavior," the researchers write. They add, "The data make clear that with regard to consent and probable cause searches, an increased targeting of black males was completely unjustified by any corresponding increase in contraband hit rates." In other words, the greatly increased number of police searches of black male motorists has not resulted in finding any more drugs, illicit guns, or stolen property.
The idea that police tend to treat black Americans more harshly than white Americans was further bolstered by a new study by the Harvard economist Roland Fryer, Jr., that assesses racial differences in police use of force. Fryer analyzed what happened after black, white, and Hispanic citizens were stopped by police in ten cities. Fryer reports that with regard to non-lethal uses of force, such as being grabbed, pushed into a wall or onto the ground, or handcuffed, "blacks and Hispanics are more than fifty percent more likely to experience some form of force in interactions with police than whites." There was one notable exception to this pattern: Despite the vivid stream of video testimony of police shootings of black men, "blacks are 23.8 percent less likely to be shot by police, relative to whites."
In any case, the North Carolina and Harvard studies strongly indicate that police do subject African Americans to greater unwarranted scrutiny and harsher treatment. "We can conclude that blacks in North Carolina appear to have good reasons to be mistrustful of the police, and that these trends appear to be growing over time," the North Carolina researchers warn.
Fryer suggests that unwarranted police encounters demoralize members of minority communities and could contribute to sustaining aspects of racial inequality. "If, for instance, blacks use their lived experience with police as evidence that the world is discriminatory," speculates Fryer, "then it is easy to understand why black youth invest less in human capital or black adults are more likely to believe discrimination is an important determinant of economic outcomes." He concludes, "Black Dignity Matters."