That looks like a bad shoot. The guy clearly had raised his hands hands high above his head, and he was up against the side of the car.
I don’t know all the facts, or the whole story; and that will come out in the investigation. But from what little can be gleaned from this video, this was a bad shoot by the police.
He was executed simply and only because the cop wanted to shoot him. He caused the officer some hectic time and the officer desired to shoot him because of that.