ALL THIEVES OF ANY KIND= shot on sight
Well, you never know what a CC thief may have for a weapon.
If you see a knife and he makes a furtive movement towards you - and you are armed, depending on your state law, you may be justified (in a legal sense) to take action to defend yourself.
Something along the lines of "Wow, he lunged towards me with a knife, I had to shoot as I feared for my life (or insert your state law standard here). Hmmm... there's a knife, right next to his hand."