A killer is a killer man, and thinking they wont kill someone because of their skin color is not a very bright outlook to have. I'm sorry but if I was working with someone I knew who killed someone I'd be extremely careful around them, and quit. Once I quit I'd anonymously report them. Of course I realize this is kind of a bit cowardly but I'm not gonna get got when I dont gotta get got. Now if I'm personally witnessing this I'd attempt to stop it... if I'm not outnumbered.

Unfortunately, a good cop might turn pretty bad because of this. Personally I wouldn't know what I'd do in that situation. Sure I'd like to believe I'd try to stop It at all costs but... perhaps I'd be too scared to.

That being said, the above would absolutely be no excuse to just standing and watching a murder happen. This is where guilty by association should take place.