I have two recent articles that examine racial bias in decisions to shoot using Dallas Police Data:

• Wheeler, Andrew P., Scott W. Phillips, John L. Worrall, and Stephen A. Bishopp. (2018) What factors influence an officer’s decision to shoot? The promise and limitations of using public data. Justice Research and Policy Online First.
• Worrall, John L., Stephen A. Bishopp, Scott C. Zinser, Andrew P. Wheeler, and Scott W. Phillips. (2018) Exploring bias in police shooting decisions with real shoot/don’t shoot cases. Crime & Delinquency Online First.

In each the main innovation is using control cases in which officers pulled their firearm and pointed at a suspect, but decided not to shoot. Using this design we find that officers are less likely to shoot African-Americans, which runs counter to most recent claims of racial bias in police shootings. Besides the simulation data of Lois James, this is a recurring finding in the recent literature — see Roland Fryer’s estimates of this as well (although he uses TASER incidents as control cases).

The reason for the two articles is that me and John through casual conversation found out that we were both pursuing very similar projects, so we decided to collaborate. The paper John is first author examined individual officer level outcomes, and in particular retrieved personnel complaint records for individual officers and found they did correlate with officer decisions to shoot. My article I wanted to intentionally stick with the publicly available open data, as a main point of the work was to articulate where the public data falls short and in turn suggest what information would be needed in such a public database to reasonably identify racial bias. (The public data is aggregated to the incident level — one incident can have multiple officers shooting.) From that I suggest instead of a specific officer involved shooting database, it would make more sense to have officer use of force (at all levels) attached to incident based reporting systems (i.e. NIBRS should have use of force fields included). In a nutshell when examining any particular use-of-force outcome, you need a counter-factual that is that use-of-force could happen, but didn’t. The natural way to do that is to have all levels of force recorded.

Both John and I thought prior work that only looked at shootings was fundamentally flawed. In particular analyses where armed/unarmed was the main outcome among only a set of shooting cases confuses cause and effect, and subsequently cannot be used to determine racial bias in officer decision making. Another way to think about it is that when only looking at shootings you are just limiting yourself to examining potentially bad outcomes — officers often use their discretion for good (the shooting rate in the Dallas data is only 3%). So in this regard databases that only include officer involved shooting cases are fundamentally limited in assessing racial bias — you need cases in which officers did not shoot to assess bias in officer decision making.

This approach of course has some limitations as well. In particular it uses another point of discretion for officers – when to draw their firearm. It could be the case that there is no bias in terms of when officers pull the trigger, but they could be more likely to pull their gun against minorities — our studies cannot deny that interpretation. But, it is also the case other explanations could explain why minorities are more likely to have an officer point a gun at them, such as geographic policing or even more basic that minorities call the police more often. In either case, at the specific decision point of pulling the trigger, there is no evidence of racial bias against minorities in the Dallas data.

I did not post pre-prints of this work due to the potentially contentious nature, as well as the fact that colleagues were working on additional projects based on the same data. I have posted the last version before the copy-edits of the journal for the paper in which I am first author here. If you would like a copy of the article John is first author always feel free to email.