Some years ago we were doing a deer drive at a friends farm here in Iowa. One of the drivers hit a nice 12 pointer in the jaw. I saw it running with the jaw flopping back and forth. We got lucky, my uncle shot it on the run with an old single shot 20 guage (he admitted he got lucky on that one).The person who shot it in the jaw was trying for the shoulder but shotguns are shotguns and running deer are not easy. Had my uncle not hit it in the lungs it would have gotten away. I believe that some deer shot in the jaw die quickly but most don't. IALMOST always aim for the vitals because I am not on the skill level as some of the snipers on this thread and I prefer not to let my deer get away if I can help it. With that said, I have made neck shots in the past when I felt I had no other choice.