Well, the principal is scared that she could be sued, if the Board of Ed is told and acts, they could be sued. They never think of the effect it has on the children and the teacher himself. You realize he may not be aware of his actions. Not to gang up on him... get someone else you trust at work and engage him in a conversation, where the other person (if he displays these behaviors), can comment... in passing, where as you can remind him that you asked him about it before and has he seen anyone yet. Be prepared to have Names, addresses and phone numbers on hand to give to him... and tell him to just think about it.
This is going on in Japan, as I gather. Whole 'nother ball game. The challenge is to address the problem while saving face for everyone involved.