During the filming of a scene where Denise Crosby hits Eddie Murphy in the stomach with a rubber baseball bat prop, Murphy was afraid Crosby would actually hit him instead of stopping about a foot away like all staged movie blows. She demonstrated her control on both Walter Hill and Nick Nolte to assure Murphy, but ended up hitting him anyway during a take.
The Jack Cates character played by Nick Nolte apparently became the inspiration for the Sonny Crockett character on the later hit television series Miami Vice (1984). 48 Hrs. (1982) actress Olivia Brown went on to be a regular on the same show.
While looking for Luther, Jack and Reggie visit an apartment in The Mission and learn they should look for their quarry "just around the corner in Chinatown." In reality the Mission is 3 miles from Chinatown.
Throughout the whole movie, Ganz is holding Luther's girlfriend Rosie hostage. She is even with Ganz on the bus when Luther comes on board to give Ganz the money. However, after Ganz shoots Luther and the bus chase begins, she is no longer seen. Not even in the interior shots of the bus as Ganz is shooting at Jack and Reggie. Later on Keyhoe tells Jack that the bus was abandoned in Chinatown but does not mention Rosie. From the point that Luther is shot until the end, there is no indication of whether or not Ganz killed Rosie or let her go.
When Reggie takes the knife from the redneck, he closes it and places it on the bar with his right hand before breaking the glasses and being told where Billy Bear's girlfriend lives. When he turns around and talks to the people in the club, the knife is clearly still on the bar. He then walks out to the street where he takes it from his back left pocket and gives it to Cates.