When I was in high school, we had a power-tripping principle/vice-principle duo that no student liked. They went about treating students as if they were bound to be in class at all times, and at no time act out of the ordinary. Frequently their bounds of control reached beyond the simple school setting. I started a petition online that accused them to something of this effect (simply nothing against the law or accusing them of any crime - simply dislike for them) asking for them to be removed from their positions.
Low and behold, they found out about the petition and pulled me out of class during an *exam*. They basically told me that it was libel and that they could sue me for it. Absolutely ridiculous power tripping coercive bastards. If I knew then what I know now (5 years later) about the law, I would have taken them as far as they wanted to go!