Why don't we go a step further and assume (without firm evidence either way at this point) that the dead guy did/said something *dangerous*.What next?
Fine, let’s do so.
The problem is that to make the shooting legally justifiable you have to demonstrate *danger* at the instant the gun was fired. Not one minute or three minutes earlier. Which, since we have the instant of the shooting on video, will be pretty difficult.
What you’re talking about is somebody taking revenge for earlier actions and then claiming that as self-defense. Which just doesn’t work, legally speaking.
For instance, if I take a shot at you and miss, you can’t turn up a day later, or even 30 seconds later, and gun me down when I am unarmed and therefore do not represent an eminent threat.
Self defense can be claimed for present threats only, not past ones or possible future ones.