Then, of course, there are those limitations. First, much of the data on shootings comes from major cities with large black populations, which might be more sensitive about race issues in policing. This is especially striking when you consider that the most famous shooting of recent years took place in Ferguson, Missouri, a small, inner-ring suburb with its own police department. “It is possible that these departments only supplied the data because they are either enlightened or were not concerned about what the analysis would reveal,” Fryer writes. “In essence, this is equivalent to analyzing labor market discrimination on a set of firms willing to supply a researcher with their Human Resources data!” Who knows how the situation may look in other cities or towns. “Relatedly, even police departments willing to supply data may contain police officers who present contextual factors at that time of an incident in a biased manner,” Fryer adds—which is a polite researcher's way of saying that the study relies on reports written by officers who may well be lying about what really transpired.
Readers also need to be cautious about how they interpret the findings. Once again, Fryer suggests blacks and Hispanics are no more likely to be shot than whites after they've been stopped by police. But as a few sharp writers have noted Monday, that doesn't tell us anything about whether people of color are being stopped excessively in the first place. And in parts of the country, they almost certainly are. In one-third white Ferguson, blacks made up 93 percent of arrests and 85 percent of traffic stops. Philando Castile was stopped by cops 52 times in 14 years before he was shot and killed by an officer in Minnesota last week. Fryer's paper may simply be telling us that deadly bias in American policing has less to do with how cops decide to pull the trigger and more to do with how they interact with the community overall. Hopefully, researchers will be able to replicate his in-depth analysis of Houston in many more cities to give us a better sense of whether that is actually the case.