Posted on December 2, 2016

Race and Police Killings

Robert VerBruggen, The American Conservative, December 1, 2016

A bit before Thanksgiving, John Lott and Carlisle Moody of the Crime Prevention Research Center released new research on race and police killings, finding, among much else, “no statistically significant difference between killings of black suspects by black and white officers.” It’s received a handful of light, friendly writeups in conservative outlets while being ignored in the mainstream media.

That’s a shame, for two reasons. One, the study rewards careful, critical reading–I often found myself pausing to consider exactly how Lott and Moody had set up their analysis and what, precisely, we can infer from the results. And two, the authors freely posted their data online so anyone who wants to can reanalyze it.


Probably the biggest limitation of the study is that while officers’ races play a prominent role in the analysis, Lott and Moody are missing that information in two-thirds of their cases–and the information they do have largely comes from media sources, which (as Lott and Moody concede) are far more likely to note an officer’s race if the officer is white. Therefore, the results may overstate the role of white officers in these cases.

Anyhow, on to said results. In general, there are clear patterns in the raw data, but they often go away when Lott and Moody add statistical controls.

For instance, Lott and Moody are not the first people to notice that suspects shot by black officers are disproportionately black. This doesn’t really mean anything by itself, because cities with higher black populations will tend to have more black suspects and more black officers, causing the two to cluster together in the data. But when Lott and Moody account for myriad other factors (such as the demographics of the city and the police department), there seems to be no relationship at all between the races of the officers and the races of the suspects they killed.

In another analysis, limiting the data to cases involving white officers, Lott and Moody look at the question of whether the suspect was armed. Again there’s a basic pattern that others have noted before: blacks shot by police are indeed more likely to be unarmed. But this, too, falls by the wayside when additional controls are added, such as whether the suspect was involved in a violent crime–though the authors suggest there is still some evidence of “rational discrimination,” as it seems that police kill more unarmed people in areas with high black populations and high violent-crime rates. “The more violent crime in the city, the more likely it is that officers will have experience with dangerous suspects who are likely to resist, fail to obey orders, or threaten other civilians,” they write.

When it comes to unarmed people killed by police, I always turn to Nick Selby, who collects detailed information on these cases in his peer-reviewed database and coauthored a book covering all of the incidents that occurred in 2015. He often emphasizes that “unarmed” is not the same as “not dangerous,” and that context is key to understanding each incident. When I asked what he thought of the study, he and his coauthors prepared a response saying that the results are basically consistent with their own. They noted, for example, that most killings of unarmed civilians begin with a member of the public contacting the police, not with an officer targeting and stopping a specific person of his own volition–and that the “ratio of black to white to Hispanic of unarmed people killed by police in this cohort . . . was identical to the ratio within the group stopped by police. There was no bias in selection by police that favored blacks over any other group.”