To measure the breadth of arrest disparities, USA TODAY examined data that police departments report to the FBI each year. For each agency, USA TODAY compared the number of black people arrested during 2011 and 2012 with the number who lived in the area the department protects. (The FBI tracks arrests by race; it does not track arrests of Hispanics.)
The review did not include thousands of smaller departments or agencies that serve areas with only a small black population. It also did not include police agencies in most parts of Alabama, Florida and Illinois because those states had not reported complete arrest data to the FBI.
The review showed:
• Blacks are more likely than others to be arrested in almost every city for almost every type of crime. Nationwide, black people are arrested at higher rates for crimes as serious as murder and assault, and as minor as loitering and marijuana possession.
• Arrest rates are particularly lopsided in some pockets of the country, including St. Louis' Missouri suburbs near Ferguson. In St. Louis County alone, more than two dozen police departments had arrest rates more lopsided than Ferguson's. In nearby Clayton, Mo., for example, only about 8% of residents are black, compared with about 57% of people the police arrested, according to the city's FBI reports. Clayton's police chief, Kevin Murphy, said in a prepared statement that "Ferguson has laid bare the fact that everyone in law enforcement needs to take a hard look at how we can better serve our communities and address any disparities that have existed in our departments for too long."
• Deep disparities show up even in progressive university towns. USA TODAY found police in Berkeley, Calif., and Madison, Wis., arrested black people at a rate more than nine times higher than members of other racial groups. Madison Police Chief Michael Koval said most of the arrests happen in the poorest sections of the city, which are disproportionately black, and where some residents have pleaded for even more police presence. Still, he said, "I think it would be remiss to suggest the police get out of this whole thing with a free pass. We have to constantly be doing the introspective look at who we are hiring and how we are training."
• Arrest rates are lopsided almost everywhere. Only 173 of the 3,538 police departments USA TODAY examined arrested black people at a rate equal to or lower than other racial groups.
Phillip Goff, president of the University of California Los Angeles' Center for Policing Equity, said such comparisons are "seductively misleading" because they say more about how racial inequities play out than about what causes them. Those disparities are closely tied to other social and economic inequities, he said, and like most things that involve race, they defy simple explanations.
"There is no doubt a significant degree of law enforcement bias that is the engine for this. But there's also no controversy that educational quality and employment discrimination lead to this," he said. "It's not an indicator of how big a problem there is with a police department. It's an aggregator of what's going on in the community."
Still, he said, "there's some level of disparity that is a warning sign."
Whatever the causes, Harris said such pronounced disparities have consequences. "Believe me, the people who are subject to this are noticing it and they're noticing it not just individually but as a group. It gets talked about, handed down, and it sows distrust of the whole system," he said.
