Thanks to the Google School of Law, people seem to think that the First Amendment protection on free speech allows them to say any nasty thing they want. It doesn't.
Ebony Dickens, of Atlanta, Georgia, learned that the hard way after she posted a noxious rant on Facebook calling for black people to "rise up and shoot at every white cop in the nation starting NOW." Her rant goes on, "Might kill at least fifteen tomorrow. I'm plotting now." She thinks she's bullet proof, and writes, "Freedom of speech tho. So when you can absolutely show me in the 1st amendment where it explicitly says you can't say 'kill all cops,' then I'll delete my status."
Well, she deleted her whole Facebook account hours before local police, FBI, DHS, and New York Police arrested her and charged her with disseminating information related to terrorist acts. More charges may come later.