Lamenting the thumbs down sign for the pepper spray use by police should give you a clue. Do you not think that such use is already employed by police? It does not stop everyone in their tracks; neither do stun guns or bullets. Aggressive, violent assailants have been shot multiple times and continue to struggle. That's why "shooting in the knee" or to wound is not an option in most cases. I am not a cop and can tell you that if my life is threatened, I am not going to defend myself to the minimal degree! It is simply survival. We are now letting the criminals win.