The right to freedom of the press is extensive. If the information is true or if the information is form public sources, then you are largely without remedy. If they have truly defamed you, consider reviewing the situation with an attorney. I doubt it will be worth the effort.
We do not have a client/attorney relationship until you make an appointment, we discuss your case face to face, I accept a retainer, and we explictly agree to enter into representation.
I agree with my colleague, but I would also point out that the person you write about is not barred from filing a lawsuit merely because she/he would probably lose. In other words, just because something is legal doesn't mean that it would not cost you money proving that it is legal. In addition, I would watch out for statements that are not very specific. Saying that "Fred hurts people--watch out" is very hard to defend. Saying that "Fred hurt me" is not hard to defend.
Thomas Jefferson said "If you are angry, count to ten. If you're really angry, count to a hundred." (I paraphrased). It is usually a good idea to wait a day or two before you hit "Send" or "Submit" when you are angry. Things usually look better afterwards, and you will be far less likely to have to hire an attorney.
Fun disclaimer: No Freds were hurt in the making of this answer, and Fred didn't hurt me.
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