You can sue for libel if the person who distributes the information does so knowing that the information is false and that it will damage your reputation in the community. Though you may disagree with what he is saying, truth is always a defense to such a lawsuit. I am not suggesting that information he distributes is true, but these kinds of cases are very difficult to prove and win. Extortion and blackmail are not causes of action in a civil setting, and are normally brought in a criminal court.
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