ok, imagine being in court watching a tape. theres two men standing together, one looks particularly agressive towards the other one, the other one seems to be backing off/avoiding the other person. The other person will not stop, suddenly the person being harrased hits the other person in the face, knocking them on the ground, he then runs.

Would you find him guilty? I wouldnt. However if both were agressive looking towards eachother then one randomly sucker punches the other then stands there gloating then thats when you would be found guilty, otherwise its pretty easy to tell it was in sd.
"They say the only way to kill a lion is with a rear naked choke, but I'd just kick it in the head"