That would be a murder. About 11% of police killings turn out to be illegal killings in the US.
EDIT:
1. Nope, didn't notice. I was stopped the other day because something was hanging under my truck. I told him I had a concealed carry permit and I had a loaded weapon in the console next me. He said "That's cool. Just wanted to let you know something's dragging under your truck, and you need to check it out." He never once tried to choke me, didn't ask for my gun, and did threaten any violence upon my person. I thanked him and he said to have a nice day. Again...no choking, threats or violence upon my being.
2. Sounds like it's already under the rug.
3. It's not systemic....really! How much personal interaction do you have to be able to suggest it's systemic?
I have never had a bad interaction with the police either. However it helps to be white and have a carry permit. The weapons permit assures the cop that you are not a criminal and have had extensive background checks.
P.S. Conceal carry holders who are found to have killed illegally are only about 2%.