If we were the police officer in the situation, who’s to say we wouldn’t do the same thing? You’ve gotten called in because someone’s shooting up the place, you’re trying to seek out the killer as fast as possible, and you literally see a guy pinning someone on the floor with a gun to their head.
Of course this was a terrible thing. Of course the cop needs to be stricken from the force for this. But this all likely has nothing to do with racism, unless further evidence appears.
Jumping to conclusion is our country’s biggest crime.