There was a full (and much publicised) enquiry into the tube shooting and it was found that the police did not act appropriately and were therefore culpable. As for the table leg, I am not sure I agree with Ian on this so much. If the police are pointing guns at me, my response would be to drop everything (no matter what it is) and do what they say. You can discuss the specifics later and even take the police to court for mental anguish or similar but at least you CAN do that rather than having to rely on your bereaved family to do it.
Though there is always the panic... I did a personality test recently which said that I have the sort of personality which reacts well to crisis (thinking rationally rather than irrationally) so I am more likely to think clearly unlike some who may do something stupid and maybe the police need to think about those who react that way and take that into account.