"blame on 'evil racist cops'"? They're employees. Doing what the bosses say; hired by the bosses. If they're racist, guess who selected for that trait.

If any enemy country had these outcomes, we wouldn't talk about police psychology or the comforts of prison life. We'd talk about the nation's distribution of power (history of slavery and dominant "white" race, systematic inequality, etc) and figure it out with cold rationality.