If my understanding of the legal system is what I think it is, you do have to go to trial. Its just you defend yourself by saying it was self defense.
Honestly, were he not a convict, his chances would likely be higher. But the fact he has a unsavory history is going to weigh into it, and may be the straw that breaks the camel's back.
This is all dependent on the jury, and whether or not they agree with me or some dumbass that believes two aggressive customers should be able to jump the counter and beat employees senseless.
lol well i know that, thats why i said hes being charged not convicted