You really need to ask this question? He is unlikely to be charged criminally, but he could be charged with assault, and perhaps sexual harassment. If he is, fortunately, he will be treated as a juvenile. Although, others may disagree with this, if it was my son, I would have him call the girls or speak to them in person and apologize for being rude, juvenile and disrespectful. It is the parents of these girls who can file the complaint with complaint that could place your son into the system -- and you don't want that. I would not let my son put anything in writing because of that, but a little bit of remorse and an apology can go a long way. AND as a parent, if you try to justify such behavior as innocent game playing, you are compounding a problem, which will only get worse.