The working titles of this film were The Rap and Their First Mistake, which was also the release title of a 1932 short made by Stan Laurel and Oliver Hardy. A 9 Aug 1930 EHW review noted that a preview of The Rap (as the picture was then called) ran for 70 min. According to modern sources, after the film's Aug preview, retakes and foreign language versions were shot from mid-Sep--1 Dec 1930. [For information on the foreign language versions, please see the record for De bote en bote.] A 15 Nov 1930 EHW news item reported that "In an effort to make Their First Mistake, originally titled The Rap...louder and funnier, Hal Roach is adding sequences to it before it is finally released for the entertainment of the millions of Laurel and Hardy fans." According to company records located at the USC Cinema-Television Library, the prison set was designed from photographs of San Quentin and Sing Sing. Although the onscreen credits and contemporary sources list Jack Stevens as the photographer, modern sources often credit Jack's brother, George Stevens.
       This was the first feature-length film in which Laurel and Hardy starred. Between 1929 and 1951, they appeared in twenty-seven feature-length, English-language films, four of which featured the comedians in guest appearances rather than starring roles. The first picture in which Laurel and Hardy appeared together was the 1921 Reelcraft short entitled The Lucky Dog, although they did not appear as a "team" until a 1926 Hal Roach short called Duck Soup. Many modern sources note that, while Laurel and Hardy worked at Roach, Laurel was actively involved in all facets of production, including writing, directing and editing, although he did not receive onscreen credit for these contributions. Modern sources also state that "the boys," as Laurel and Hardy were known, occasionally reworked gags and story lines from their shorts into their features. Among the actors who often appeared in Laurel and Hardy shorts and features were James Finlayson, Stanley J. "Tiny" Sandford, Charlie Hall, Sam Lufkin, Baldwin Cooke, and Mae Busch. Among their frequent directors and writers, both on the shorts and features, were James Horne, James Parrott, Leo McCarey and Charley Rogers .
       In addition to a Spanish-language version, De bote en bote, French, German and Italian language versions, entitled Sous les verrous, Hinter Schloss und Riegel and Muraglie, respectively, were also produced. No information concerning the release of these versions in the U.S. has been located. Boris Karloff may have appeared in the French version (some modern sources state that he played "Tiger," but another modern source asserts that Walter Long and June Marlowe played "Tiger" and the warden's daughter in all five versions.) Lucien Prival was in the German version and Guido Trento was in the Italian version. According to the company records, the production crew listed above also worked on the foreign-language versions, which were shot simultaneously after the English version was completed. Laurel and Hardy were taught their foreign language lines phonetically, and dialogue scenes were shot using each of the languages. They used this procedure for the foreign releases of several shorts, and for some shorts that were combined into feature-length films, while for other films, they shot the foreign versions at the same time as the English-language version. The cutting continuities for the foreign versions of this film, contained in the company records, reveal that the plot was slightly different: During the riot caused by Stan and Ollie's inept handling of a weapon passed to them in the mess hall, a fire starts in the warden's home. Stan and Ollie rescue the warden's daughter, and thus win their parole. According to modern sources, the fire and rescue scenes were filmed for the English version but were deleted. De bote en bote, which was viewed, utilizes the fire/rescue sequence and includes two more songs, but dispenses with the schoolroom sequence. Modern sources note that S. C. Baden was the sound mixer for all of the foreign versions. Modern sources credit John Whitaker with assisting Elmer Raguse in mixing the sound of the English version, and John Harrison and Ralph Butler with the location sound recording.
       Modern sources also include the following actors in the cast of the English version: Charlie Hall (Dental assistant/deliveryman); Sam Lufkin, Silas D. Wilcox and George Miller (Prison guards); Frank Holliday (Officer in classroom); Harry Bernard (Warren, the desk sergeant); Robert Burns (Prone dental patient); Frank Austin (Dental patient in waiting room); Otto Fries (Dentist); Robert Kortman and Leo Willis (Tiger's pals); Jerry Mandy (Convict who can't add); Bobby Dunn, Eddie Dunn, Baldwin Cooke, Charles Dorety, Dick Gilbert, Will Stanton, Jack Herrick, Jack Hill, Gene Morgan, Charles A. Bachman , Blackie Whiteford and Charley Rogers (Insurgent convicts); Gordon Douglas (Typist at desk); James Parrott (Prisoner marching in formation next to Hardy, right after the boys's recapture); Hal Roach (Prisoner marching in front of Hardy); Eddie Baker (Plantation overseer on horseback); The Etude Ethiopian Chorus (Cotton pickers); and Belle (Bloodhound). Modern sources also note that Bobby Mallon and Buddy MacDonald, playing boys fishing by a stream, were cut from the final release print, and that the incidental music scoring was by LeRoy Shield, Edward Kilenyi, Arthur J. Lamb, H. W. Petrie, Will Marion Cook, Irving Berlin, Abe Olman, M. Ewing, Frederic Van Norman, L. E. de Francesco, J. S. Zamecnik, Frieta Shaw and Marvin Hatley.