An illiterate deaf-mute whose 21-year odyssey through the legal system inspired a book and a TV movie is entitled to a new hearing on whether he is fit to stand trial for murder, the Illinois Supreme Court ruled Wednesday.

If Donald Lang, charged in the slaying of a Chicago prostitute, is found unfit for trial and shows no prospects for improvement within a year, he must receive a hearing on whether he may be released from a state mental institution, the high court said.