An attorney with the New Civil Liberties Alliance asked the U.S. Court of Appeals for the Second Circuit on Friday to lift an 18-year-old gag order that barred a former Xerox executive from speaking out about his long-ago prosecution by the U.S. Securities and Exchange Commission, arguing that the enforcement was an unconstitutional prior restraint against free speech.

Lawyers arguing the case of former Xerox Chief Financial Officer Barry Romeril sought to knock out as unconstitutional a little known but often used tool at the SEC’s disposal in settling civil enforcement cases.