Although reformers and activists have been calling on law enforcement to hire more black cops for decades, new research suggests there may be measurable advantages to more diverse police forces, at least in certain circumstances.
“Diverse police departments are particularly able to alleviate tensions in cities … where you have pre-existing racial, ethnic tensions,” said Joscha Legewie, a sociologist at New York University. He conducted the research with Columbia University’s Jeffrey Fagan, a legal scholar.
Consider two hypothetical cities, both with populations half white and half black. The cities are identical except for their police forces. In the first city, there are no black police officers, but in the second, one out of eight officers is black. Because the second city has a more diverse police force, Legewie would expect there to be 18 percent fewer killings of black civilians by police there than in the first city, based on the data he and Fagan collected.
The pattern was less pronounced in cities with large white majorities or where more than two major racial or ethnic groups divided the population.
There are only a handful of police departments where the share of black officers is at least equal to the share of the population that is black. A few examples are the departments in Austin, Texas; Dallas; Denver; Los Angeles; and Washington, D.C.
Legewie and Fagan used data on police shootings from the online clearinghouse Fatal Encounters from 2013 to 2015, doing their own research to fill in missing information about the races of the deceased.
He and Fagan found that in cities where the population was closely divided between races, killings of black civilians were less common when the racial composition of the police force reflected the population as a whole.
