Robert Cohen/MCT/ZUMA Press

In 2009, police in Ferguson, Missouri, arrested Henry M. Davis on suspicion of driving under the influence and took him to jail. What followed is described in court documents as "physical contact between the officers and Mr. Davis." One officer, Kim Tihen, allegedly "struck [Davis] in his head with a closed fist and hit [him] in the head with handcuffs." Davis suffered a concussion and severe facial lacerations, while an officer was left with a broken nose. Afterwards, prosecutors charged Davis with four counts of destruction of property—because his blood had dirtied the officers' uniforms.

Davis pleaded guilty to reduced charges and ended up moving to Mississippi. Officer Tihen, for her part, is no longer with the Ferguson Police Department. In 2012, after four years on the force, she won election to the city council, becoming one of the six-person body's five white members. (The sixth is Latino.) Two-thirds of Ferguson's residents are black, but the city holds elections in the spring, making for low turnout—in April 2012, when Tihen was elected, less than 9 percent of eligible voters went to the polls. (The Ferguson police force is even less representative of the city’s African American majority: Just 4 percent of its members are black.) Last week, after police cracked down on residents protesting the killing of Michael Brown, an unarmed teen, Tihen and the rest of the city council issued a statement calling on demonstrations to cease at dusk.