“WHY DOES THE VIDEO START WHERE IT DOES??????”
It really doesn’t matter in this case what proceeded this. If he shot the victim in the back as he was fleeing, as the video shows, it was murder...
See 133. The video is altered. Close your eyes and listen to the audio from the beginning to about 20 seconds in. There is no continuity. The video has had some part purposefully removed. The background siren has no continuity as other sounds similarly lack continuity,
https://www.youtube.com/watch?v=Xpt7sEt3k4Y
Again, I’m not saying what the cop did was wrong, but - for all I know - the guy slugged the cop and went for his gun in the missing segment of the video. It doesn’t make the shooting justified, but it will change the nature of the charges.