I'm with grayghost here.
Problem one:
Police received 4 911 calls. Now, you're standing 100 yards away getting ready to take your shot....po-po come roaring up and see you, with a rifle. You've just broken the information chain for that officer. He will zero in on you, and while he's figuring your situation out, the perp may have time to make an escape or kill the victim.
Problem two:
Grabbing your rifle from standoff distance makes you removed from the flow of information of what is happening. You see a black guy holding a gun on a white woman. Ingrained stereotypes may take over from here. We all have them, whether we admit it or not.
You
REALLY do not know what is going on. Pure and simple. Are you sure you're not shooting an undercover cop? CHL holder who's defending himself against a crazy ex wife with a knife?
Problem three:
Lets say it is just as cut and dry as it looks. Maybe you witness the whole thing going down. Man has woman at gunpoint. Read the information we were given by the OP. There are
two perps. Does the other perp have a gun? You are entering a 1 v 2 situation. This ain't TV. This ain't the gun range. This is a gunfight, on the street, with two presumably hardened and armed criminals. They've probably shot at and maybe killed someone before. They've been shot at. They do not value human life the same way you do. Have you cleared the other car wash stalls? There might be more perps. Maybe it quickly turns into a 1 v 3 (or more) situation.
If, and its a big if, I were to directly intervene, my first aim will be to take control of the situation. If I can gain a tactical advantage with hardened cover that still gives me the opportunity to move and shoot, I would use my command voice to get control of the weapon-holder and all involved. If the weapon gets pointed at me,
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. A movement towards the woman?
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But the woman isn't off the hook, either. Who the hell is she? Is she a victim or the actual perp?
But you just don't know what's going on when you approach the situation.
All you know is that a man has a gun on a woman.
My plan of action in a situation like the one laid out is to be prepared to intervene, be on the phone with the police, and be a good witness. Begin searching for the tactical advantage to end the situation. Checking my 6 to make sure that I don't become a victim.
I'm a parent and a husband, though. I don't have the luxury of playing cowboy.
It sucks, and I'd probably never sleep again if I let something happen to that woman. But, I also can't imagine my children finding out daddy ain't coming home.