Imagine this simple scenario regarding breaking the law(a ridiculous one)?

Not as cut and dry as you make it out to be, all it would take for the "thief" to have you arrested is go to the police and LIE, "I was just walking down the road and this person assaulted me" your evidence is your word, his is a set of swollen nuts and mace in the eyes (and the knife was dropped in the bushes a block form the police station).