Speaking as an attorney and sports official (league official as well as game official), I respectfully disagree NYBamaFan. There is never any excuse for an adult to attack a child on a sports field. While I may or may not agree with the particular charge, I think that this idiot should be charged and, if convicted, he should receive at least some jail time. I don't mean that he should be sent away for years but he should have to spend some time locked up for what he did as well as receive anger management counseling. Furthermore, if I was in charge of this particular league, he would be banned from our facilities for life.
As an aside, the player involved in this was penalized for the late hit. I do not know if he was ejected from the game and/or suspended from later games. The fact that he was attacked by a parent does not mitigate against what he did. He should have to face some consequences as well.