Every studio in Hollywood turned down Ebbe Roe Smith's script. Producer Arnold Kopelson was getting to the stage of considering cable television, when Michael Douglas came across the script and pronounced it one of the best he'd ever read.
The movie was being shot on locations in Lynwood, California when the 1992 Los Angeles riots began. By April 30, the riots were sufficiently disruptive to force filming to stop early that day. Film crews produced more footage inside of Warner Brothers Studio in Burbank as the riots continued. By May 4, when the crew intended to resume in Pasadena, initial requests to do so were denied, causing delays. The tension around the riots, something that the filmmakers deemed to have an effect on the finished film.
In the scene in which the drive-by car crashes, there is a mural of Christ on the wall. This same mural is also present in Colors (1988), also starring Robert Duvall as an LAPD cop, in the scene in which the police officer played by Sean Penn, spray paints a kid's face.
"London Bridge is Falling Down" is heard several times in the film. Prendergast (Robert Duvall) sings "London Bridge" with his wife (Tuesday Weld) on the telephone. The same tune is played by the snow globe that D-Fens buys on Wilshire. The lyrics to the song are "London Bridge is falling down, falling down", a reference to the movie's title. A bridge appears on the retirement cake of Detective Pendergrast, then moments later, he punches Detective Lydecker (D.W. Moffett), who falls into the bridge. Prendergast also planned to retire to Lake Havasu City, Arizona, where the old London Bridge was moved, in 1971. D-Fens also says to Nick The Nazi (Frederic Forrest) "I'll fall down", and in the "what's wrong with the street?" scene, the construction worker explains he is there to keep people from falling in, and when D-Fens shoots out the phone booth, a cyclist falls down off his bicycle.
Where D-Fens (Michael Douglas) buys the snow globe for his daughter was filmed next door to the exterior shot of the Kobra Kai school (when Daniel is having lunch with his mother) in The Karate Kid (1984).
The Korean American Coalition protested the film for its treatment of minorities, as well as the South Korean grocer. Because of this, and the boycott threats that followed, this movie was banned in South Korea.
Joel Schumacher envisioned his friend Michael Douglas in the lead role. However, Douglas planned to take a break from acting, as he had just done two films back-to-back, and desired to spend some time with his family. Douglas agreed to read the script after Schumacher's urging, and declared it one of the best he had ever read, taking the role immediately. The presence of such a popular actor as the lead allowed the film to get a much higher budget. Douglas, believing the film to be important, agreed to take a much lower salary, so the film could also have more money to be made.
The scene where D-Fens (Michael Douglas) shoots out the phone booth is the same shopping center where Kane and Dooley (Eugene Levy and John Candy respectively, go to Bruno's gym called the Sport Pit in Armed and Dangerous (1986). That scene was filmed behind the Subway and Mikasa restaurants shown in this film, so it doesn't look the same, but it's the same building.
In the surplus shop sequence, the homophobic Nick pulls a gun on D-Fens and tries to pinion him from behind while repeatedly and rapidly crying "give it to me!" : this may have been intended to bring to mind a homosexual encounter, thereby implying that Nick is as gay as the people he hates.
The scene where Sandra (Rachel Ticotin) and Detective Prendergast (Robert Duvall) have lunch was filmed only two miles (three and a quarter kilometers) from the Cunningham family home in Happy Days (1974).
Near the end of this movie, Prendergast (Robert Duvall) says to the Fosters that his idea of paradise was making babies. In Species (1995), Sil (Natasha Henstridge) says to John Carey (Whip Hubley) that she wants a baby (to reproduce her alien offspring). Andrzej Bartkowiak was the cinematographer for both films.
The trivia items below may give away important plot points.
As Bill Foster gets closer to home, the weapons he acquires become more lethal, as do the people from whom he acquires them. First, he acquires a bat from the store owner, then a butterfly knife from the gang member, a few minutes later an Uzi from the same gang members car, and finally a rocket launcher from the skinhead.