If that is true, and he moved to get that gun...especially after being expressly told not to reach for the gun (or there would be life ending consequences), it's justified all day long. He had already threatened someone with the gun, and now he is moving to get the gun after they told him not to touch it. I believe it is safe to presume that reaching for the gun showed intent to do violence. He wouldn't reach for it to hand it to the cops, especially after they just said "if you go for the gun, we will shoot you" (paraphrase). So, I don't see how anyone in their right mind could call for a murder prosecution...if he had a gun and moved towards taking possession of it. Sure, it "looks bad" because the cop is on top of him and at close range. It's ugly. It has bad optics. I have news for you though, guns fire up just as well as they do down.
But, I will wait for all the facts before rendering an educated opinion on whether it is justified or not.
Lot of conflicting stuff coming out. Some "framing" angles with gun falling out of pocket after he was shot.
Guess we will find out soon or we will get Hillary'd.