a person is free from criminal prosecution under their "freedom of speech" rights, but not from civil liability. If he were to say such things about my daughter(s) I would be suing his arse so fast his head would spin, and I would hire the best publicity firm to cover the run up to the trial, and the trial itself, dig up every hooker he has slept with to testify, and thrash his reputation.

You are free to speak what ever you want about anyone, but be ready for the slander/libel suit which will inevitably follow.