Mr. District Attorney is a 1941 American comedy crime film directed by William Morgan and written by Karl Brown and Malcolm Stuart Boylan. The film was based on the long running and popular radio series Mr. District Attorney. It stars Dennis O'Keefe, Florence Rice, Peter Lorre, Stanley Ridges, Minor Watson and Charles Arnt. The film was released on March 27, 1941, by Republic Pictures. It was followed by a sequel Mr. District Attorney in the Carter Case later in the year, with different actors in the leading roles.