Folks,
There are too many factors to say what you would do one way or the other. Many of the leading defense experts say do nothing; be a good witness.
Sorry, but most of us are good shots, not great, though as men we tell ourselves we are. I am SRT qualified, Executive Protection qualified, and I am an agent with the Army's CID, but I can't say that I would start putting rounds downrange.
Are you sure that once you shoot, he is not going to get a shot or shots off? I saw the two to com, one to the head post, and whatever. I've seen a lot of federal agents shoot, and I'm not very confident that many of them could make the shot under stress.
And do you ever throw rounds at the range? For most of us the answer is probably. Even if it's every once in a while. Are you sure you won't miss and spark a gunfight, which possible kills the person you were saving or even yourself. Gunfighters miss all the time. And I'm talking about cops, who generally have more training than a lot of the people on this post. The question is: how good are you? Most people I know are not very good at appraising their own shooting skill.
Law is also a critical factor, too. If I'm not mistaken, Florida requires you to retreat as long as there is an avenue of escape, but Alabama lets you whack a car-jacker.
Mr. Capital Punishment,
If you ever shoot someone pray that no one associates your name with that post. We shoot to stop. Period! The army, of which I am a member, shoots to kill (actually wound, but that's some theoretical crap about it taking two soldiers to care for a wounded one). So you put one in the BG's brain bucket and you had better be prepared to articulate why you did it. If you come across as I'm ready to kill any bad guy stupid enough to cross my path, the defense, media, and media influenced prosecutor is going to have a field day.
"Mr. Punishment, is it not true that you didn't really need to fire that head shot; that you were simply looking to kill some one?
No? Well did you not one post a message where you stated that you would be happy to remove someone from the 'gene pool.'"
It's downhill from there. It doesn't matter if what you did was right or wrong, but how it is perceived.
There is no easy answer. In some situations, you may shoot based on nothing more than things which you can't articulate, a feeling, a premonition. In others, you may sense that there is no need to shoot. That the criminal is merely posturing. I can't be sure and neither can anyone here.
Regards to all,
Chuck Ames
He who knows neither himself nor his enemy is a fool, and will meet defeat in every battle.
~Sun Tzu