Cofty and Simon,
A little off topic, perhaps, but I think still worth stating; your remarks about armed police are quite correct.
This was confirmed a few years ago by a former firearms instructor at the Police Training Academy, who readily volunteered that not all police have the necessary skills to be armed (as in the UK, the police in this country - New Zealand - are also largely unarmed).
Furthermore, those police trained to use firearms are taught to aim for the body trunk, which is most likely to result in a fatal wound. The consensus amongst all that have ever fired a hand gun (myself included) is that you are doing quite well to even hit the target at all, let alone be selective about whereabouts on the target the bullet is going to land. You definitely aim for "the centre of the biggest piece that you can see" if you expect any success! As for the idea of trying to "shoot to wound" with a high-powered weapon; if you have ever witnessed the destruction that a slug from such a weapon does to an animal, you would quickly shed yourself of such impractical ideas (again, pretty much the consensus amongst hunters).
"Shooting to wound" might work in a cowboy movie - in which the victim is a paid actor - but that is about all!
Contrary to what some believe, the police are not instructed to shoot to wound - and that was from the Commissioner for the Police Service in the Australian State of Victoria (and I don't believe it to be any different in the UK or elsewhere).