Suppose you draw your weapon and have every right to do so. You tell the BG not to move. Whats to keep him from running away if he so chooses to do so. You can't shoot him in the back or anywhere else for that matter if he is trying to flee the area. Is this really something to even consider doing to try to keep someone there at the scene? It's good for keeping the BG at a distance from coming at you, but is it practical to think you can keep someone from running away by pointing a gun at them?