On May 5, 1970, the day after National Guardsmen had shot and killed four students at Kent State University, Keith Green was arrested at the University of Oklahoma for carrying a Viet Cong flag in violation of a state law prohibiting the display of a "red flag or emblem of anarchy or rebellion". After 12 lawyers had refused to defend the student, Jones took the case and was promptly dismissed from the Enid, Oklahoma law firm where he was employed. Jones argued in court that the disloyalty statute was unconstitutional and the judge dismissed the case, overturning the statute. Later Jones would go on to represent Abbie Hoffman, the radical Yippie, when Oklahoma State University refused to let him speak on campus.