I'm trying to find a title of a movie?

There was a movie I saw a long time ago where a black man in a mostly white city was being tried for a crime. But a trick was played by the defense.  One of the lawyers would switch clothes with the defendant before coming into the court room and all the white witnesses looked at the faux defendant and said, "yes that's him, he did it" . And at the end of the trial the defense came clean with the deception, which should of discounted every witness.  Does anyone remember the name of that movie?