For the first portion of my post I'm going to ignore legalities and focus on another aspect of the scenario.
Can you tell which customer was armed before he got up and started shooting? I could easily tell when I watched the video the first time, before I knew who was the CCW. Watch the video again and see why. Then, perhaps, think about what you would do in a similar situation so you wouldn't stand out from the rest of the patrons the way this guy did.
Ok, now legalities. You MUST watch this video to see the whole encounter. If you read my assessment based on the excerpt in Colin Noir's YT video, you will not get the full picture.
https://twitter.com/NuanceBro/status/1611808197316075521
Saying that the guy was shot while leaving is sort of tricky. Maybe he's leaving, maybe he's just going to make another lap of the room. Maybe he's checking to see if anyone is outside the store before he herds everyone in back to shoot them. It's hard to know what is really happening there.
So the CCW starts shooting. I think that it would not be hard to argue that this is justifiable. Not a nice super-clear cut case of self-defense, but I think it's workable if the CCW doesn't say anything stupid. If he says something like: "When he started leaving, I shot him." he's in trouble. If he says something like: "The guy was pointing his gun at everyone and when he turned away from me for a minute, I shot him." he might be ok.
The Bad Guy goes down and drops his gun. Maybe the CCW saw the gun go flying or maybe he didn't.
The guy is down but moving. The CCW advances and keeps shooting. Everything is happening pretty fast. Still potentially a workable self-defense case, IMO, but things are moving farther away from the "ideal" self-defense case.
Now the guy is down and not moving and the CCW advances and shoots him at very close range--looks like the last shot was in the head. Maybe he thinks the guy still has his gun and is playing possum. Again, it's all happening pretty fast and maybe a good lawyer can make this shot fit a self-defense scenario but I would really be scared if I were the CCW watching that video in court.
The CCW reaches over and picks up the BG's gun. Now the CCW can see that the BG is down and not moving, he knows he shot him in the head and he knows that he has the guy's gun. At this point it's hard to argue that the CCW is still in a self-defense scenario.
The CCW shoots him again in the head. That looks an awful lot like murder. I don't know exactly how the law works to the detail required for something like this, but maybe it's possible for the forensics to show the guy was already dead before this last shot and perhaps the CCW's defense attorney can argue that point into a charge less than murder.
Knowing when to stop is very important.
