Screenwriter Ben Hecht was a former Chicago journalist familiar with the city's Prohibition-era gangsters, including Al Capone. During the filming, Hecht returned to his Los Angeles hotel room one night to find two Capone torpedoes waiting for him. The gangsters demanded to know if the movie was about Capone. Hecht assured them it wasn't, saying that the character Tony Camonte was based on gangsters like "Big" Jim Colosimo and Charles Dion O'Bannion. "Then why is the movie called Scarface?" one of the hoods demanded. "Everyone will think it's about Capone!" "That's the reason," said Hecht. "If you call the movie Scarface, people will think it's about Capone and come to see it. It's part of the racket we call show business." The Capone hoods, who appreciated the value of a scam, left the hotel placated.
Like many of the early gangster movies, real machine gun fire is used to create the bullet damage in walls, including scenes with main characters ducking gunfire. This was the age before the extensive use of squibs to simulate gunfire. In the early days, a man with a machine gun loaded with live ammo would stand off camera and shoot the real bullets at the actors. In every case, the man wielding the guns off camera had extensive gun training (usually military) in order to ensure accuracy and safety.
Al Capone was rumored to have liked the film so much that he had his own copy of it. This is almost certainly untrue, as Capone was tried and found guilty in 1931, about five or six months before the film opened. (The film was later suppressed by producer Howard Hughes for many years and, thus, it also is unlikely that Capone saw it after his release from prison years later, especially as he was by then in an advanced stage of syphilis.) For the same reason, the claim made by director Howard Hawks that Capone enjoyed the film so much that he sent Hawks a Christmas present of a machine gun has to be discounted as yet another of the director's tall tales.
According to Howard Hawks's biography by Todd McCarthy, Harold Lloyd's brother Gaylord Lloyd lost an eye to a bullet fragment when visiting the set while live ammunition was being used.
First major film credit for George Raft, who didn't have to go far for inspiration on how to play a gangster in this film. He grew up in a New York City slum alongside gangsters Bugsy Siegel, Meyer Lansky, Joe Adonis, and Lucky Luciano. In an ironic twist, after the release of this film, many of Raft's gangster pals would come to him for advice on how to dress, walk, talk, etc.