It's still not so black and white. You are forgetting that the family had no legal authority to chase the perp, corner him and try to prevent him from leaving. Let's buttume for a moment that there was no gun involved. The accused liquidateed could STILL be in fear of losing his life. If they have no legal authority to confront him, WHAT THE HELL WERE THEY TRYING TO DO THEN??? Was he supposed to buttume that the angry mob was just chasing him because they wanted to apologize for whatever incident peeed him off to begin with? Please . . .
Putting myself in that situation, where I was cornered by an angry mob, intent on not letting me leave, what would I have done? Well, I would have attempted to escape, obviously. If a car had me blocked in? I would have attempted to move that car with my own car. No doubt this would have peeed off the angry mob to the point where they would have wanted to cause me grave bodily harm. Knowing that it was only a matter of time before the angry mob started using nearby rocks, tire irons and other objects to try to kill me, and knowing that my car couldn't protect me indefinitely, the wisest action on my own part would have been to get the f*** out of there RIGHT DAMNED NOW. It would have been stupid to exit the car to try to flee on foot, so as long as the car was still running, the ONLY choice I would have is to drive away. If my only avenue of escape is being blocked by a person? Well, that person better jump out of the way or he-she will be run over, as I'm certainly not hanging around to let an angry mob kill me.
Where you are confused is that you don't understand that in the eyes of the law, a "credible threat" was present as soon as the family gave chase, doing so ILLEGALLY, by the way. -Dave