Chris Mooney, who wrote "The Republican War on Science" and "Inside the Republican Brain: The Science of Why they Deny Science - and Reality", has an interesting article reviewing some of the attempts to understand what in people's brains drives the racial bias that might lead cops to be more likely to shoot black men or boys than whites. It's called "The Science of Why Cops Shoot Young Black Men".
Importantly, he notes that active/conscious racial animus need not be present, and folks may consciously wish they did not have a racial bias. But people still do. I have not read his other stuff, but I like the fact that in this article the tone is that of "we're all in this together and all suffer some varying amount of subconscious bias." The titles of his books sound more likely to inflame than lead to understanding, but I suspect the substance is less inflammatory. From other articles I've read by him it sounds like his looking into these psychological/social science studies has made him more compassionate toward those who hold different political views.
I'll be brief because I'd rather you waste time reading the article than my stuff, but here's one other interesting link from the article. This link is for the implicit association test (IAT) that one can take online to get a sense for the degree of implicit bias one has. I thought I was going to be more "special" than I was on taking the test, but would love to see a more fleshed out score than just by category...