Kill someone?, Like put yourself in a position where you have a weapon (gun prefferably) and try to imagen if you'd actually go through with it... now you could say this person was coming at you with a knife or you really hated this person.. or whatever.. but if you think about it you're still murdering.
And if I were in that situation I feel that I could kill someone or fire at this person.. if they were indangering me and trying to kill me.. or if they were trying to hurt my family friends.. or just some physicopath going insane.. I don't think it's fair for me to kill someone.. but I believe I could do it... however it may be a different story when putting myself right there on the spot.. but yeh..
But yeh this just randomly crossed my mind, what are you capable of doing?
btw, all laws are involved and you'd either go to jail.. or death centance.. or if you lucky get away with it lol

