I have seen a lot of bad faith cops on https://ns.reddit.com/r/Bad_Cop_No_Donut/, but most of the time, they don't kill the suspect.

This is the best database that I have found so far for shootings by police and at least they tell you if the suspect was armed, but yes more information is always better...

But the main issue is that even if the cop was found to use excessive force, there are no real consequences, most of the time.