I'm pretty sure they could make an assault charge stick to you. They'd get MAYBE a ticket for riding against traffic, but I doubt that, and even if they did it's probably $20. You'd get an assault charge, and IMHO rightfully so.

Someone just made a post elsewhere in the last week that I think is relevant. The topic was drivers who felt it was OK to run cyclists off the road to "teach them a lesson" because they BELIEVED that the cyclist had disobeyed some law, and that it was their right/duty to be judge and jury. I can't find it by searching, but it went along the lines of:

"you're not the police/judge/jury, you don't have the right to punish people who are breaking the law."

But he was...

"no."

Yeah, but he...

"NO."

You don't understand, he didn't....

"N O !"

Perhaps the cyclist is wrong (ok, probably) perhaps not. In neither case is intentionally causing harm to him justified or even legal. He'd have every right to persue you in court. Someone else's wrongdoing does not excuse anyone else's.