Batter Hitting Catcher on Backswing-Repeatedly

[easygoer]

Let me make this as simple as possible. The coaches of this team are total redneck a-holes. Their kids will spike yours if possible when running to the bag on a force play. I have seen them run over fielders attempting to catch pop ups. They will truck your catcher even if there is a clear path to the base. Pretty much every chicken *hit thing you have ever heard about they will do.

For the last 3 years the only time i have seen the catcher hit on the warm up cuts at the plate were against this team. They do it repeatedly and until an umpire makes them stop. I was just curious what specific rule should be used to stop their tactics.
Saw them play yesterday and their batter interfered with the catcher on a throw down to 2nd. The coach complained, again, two earlier instances that appeared to be batter interference were not called, the umpires finally called the kid out for batter interference on the third instance.

Again, not a question about what they are doing or why, only about the specific rule that should be enforced to stop it,

Thanks

Easygoer