Canadaicon is big on the use of "reasonable force". If a 150lb. crackhead breaks into my house armed with a knife and my wife shoots and kills him, she may not be punished. I am 6ft. 1in. tall and weigh 230lbs., if I do the same thing there is every liklihood that I would be charged because I should be able to physically subdue him. That is the way it was explained to me by a LEO.