Jackie Swanson performed the high fall on her own, trained by legendary stuntman Dar Robinson. Also, the stunt was done using an airbag covered with a life-size painting of the driveway and cars, which, like a foreground miniature, visually blends into the real scene. Thus, the editor is able to hold the shot until just as she makes contact with the airbag, for greater realism.
Mel Gibson turned down starring roles in The Fly (1986) and The Untouchables (1987) in order to do this movie.
Casting director Marion Dougherty first suggested teaming Mel Gibson and Danny Glover. She arranged for Gibson to fly in from his home in Sydney, while Glover was flown in from Chicago, where he was appearing in a play, to read through the script.
On E! True Hollywood Story (1996), Gary Busey says he was hired to play Joshua because they were looking for someone big and menacing enough to be a believable foe for Mel Gibson. Busey also credits the film for reviving his failing movie career.
Mel Gibson and Bruce Willis were considered for each other's roles in Lethal Weapon (1987) and Die Hard (1988), and both movies were produced by Joel Silver, with music by Michael Kamen. Willis was offered the role of Martin Riggs, but turned it down, and a year later he did Die Hard (1988). Gibson was considered to play John McClane, along with his co-stars from The Expendables 3 (2014), Harrison Ford, Sylvester Stallone, and Arnold Schwarzenegger, but they all turned it down. Coincidently, the script for Die Hard with a Vengeance (1995) was briefly considered to be filmed as a Lethal Weapon sequel.