My once (and probably future) co-author Nick Selby has this piece in the Washington Post:
But a closer look at some statistics shows that the problem is not necessarily an issue of racist cops, and that means fixing the criminal justice system isn’t just an issue of addressing racism in uniform.
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Some racial disparities in treatment by authorities actually appear to be the result of state laws intended to crack down on offenses like drunk driving and scofflaws that have, instead, had the effect of ensnaring poor people in a revolving door of debt, courts, collections firms and police.
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Suspended-license or no-license tickets are expensive. Why were so many blacks and Latinos driving on suspended or missing licenses?
Poverty.
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But the way Texas tracks stops obscures the broader unfair effects of the law on poor people, and makes it look, instead, like police are the problem. In our subject city, less than 7 percent of the population is black, but in 2015, 11 percent of the people pulled over there were.
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That’s as far as Texas’ racial profiling laws want police chiefs to take their analysis.
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We wanted to compare the traffic stop data to the population of the entire area where drivers came from…. and we compared that model against the race and ethnicity of the drivers who got pulled over.
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Chiefs often do not conduct [more detailed] analyses (which are required to recognize these patterns) because they spend their scarce resources complying with well-intentioned but ill-informed and often underfunded racial reporting requirements.
Interesting that TX was the locus of the research. Southern PD's seem to have a culture of "stop everyone for everything." Part of this is that they have fewer laws, so they really can approach 100% enforcement. Another part is that so many of them are or have been under DOJ or court supervision, so they play it totally straight, no discretion on all offenses and offenders. Hence the study's note that whites were actually overrepresented on the initial stop, although they were underrepresented on the citations issued.
Northern PD's are forced to exercise discretion because of the huge number of laws and people they have. And of course when you exercise discretion, you are going to have disparate impact, because that's what you're literally trying to do. See, e.g., the NYPD "impact teams" (are they still called that? Probably a poor name choice…).
Fortunately for everyone, as long as you have discretion, you can also have de-policing. If you have no impact, it can't possibly be disparate impact….
And the agencies looking to "fix the police" won't take away discretion, because then the bosses' or politicians' names will be on the blame line.
And even if you have a no-discretion policy, it's pretty hard to prove a copper saw something. Are the cellphone commandos going to record police not responding to corner crowds, dudes walking with a heavy pocket, people rolling thru stop signs, etc?
JSM