It's hard for people to imagine but police do make mistakes. They are human, and sometimes they are afraid.
In training, we qualified by making a certain number of accurate shots in seconds. Basically, almost any time you drew your weapon, you were shooting. After I graduated from the academy, I had to consciously tell myself, "DO NOT SHOOT" because it was almost a reflex at that point. Draw your weapon, shoot, observe. And, of course, after you're doing shooting, continue to yell "Put down your weak! Stop resisting!" Why? Because people will remember that if they're ever called to be a witness.
That was before everything was recorded, of course.
One thing I have to say, I'm black. I was a full time deputy and a part time police officer. In certain areas of my county, I knew certain people would be more combative or would argue. Certain people would be more compliant and submissive. There were times (most of the time, actually) where everyone was cooperative but thinking back, I always knew where I had to be more serious and focussed.
I've debated this online but black people have a serious image problem. We always have to be the coolest, the hardest, the realest, or whatever. It's taught to us at an early age. Only on black radio stations do we hear that it's okay to fight the police, kill our brothers, or sell drugs. But "It's our story and it needs to be told!" Bullshit. That's not MY story but it dominates the airwaves.
So, when other races look at us and are afraid because of our image, who is to blame? Them for being afraid or us for acting scary? It's an endless cycle of irresponsibility and people are dying as a result.
Good people are getting lumped in with the bad. Bad people are treated like heroes and martyrs. The problem is getting worse and worse.
