What Do You Do When Parents......

[TGT09]

What do you do when parents condone something at home that is serious and is most definitely not socially acceptable or otherwise? Especially if you sort of agree.

Situation:
5 y.o. dcb: I went to the principals office today.
Me: Uh oh, what happened?
dcb: I bit someone yesterday.
Me: Why didn't you go to the principal's office yesterday?
dcb: There wasn't time.
Me: Well biting isn't very nice, is it?
dcb: Dad says it was ok.
Me: Oh, so what was the other boy doing to you?
dcb: He was squeezing me around my arms.

Assuming that this is the "true" story (he's a bit of a fibber). Is the biting self-defense even though it's not something that anyone should condone? What "should" parents be doing in this instance? I almost always answer with, "did you tell a teacher"? But, if you can't physically do it then what? It's not a really a concern from a daycare stance unless he bites someone here but I'm just curious as to if there is a "right" answer to this issue.