At the beginning of the movie we hear a female voice say "Unit 2-11 officer needs assistance..." over a police radio. Near the end of the film we can hear that same sentence said over another police radio but in a different voice.
All of the exotic cars are actually replicas of Ferraris and Lamborghinis-including the ones in the chase scene.
A newspaper clipping in Woody Engstrom's shack is apparently written by Andy Armstrong. Andy Armstrong is the name of the second unit director and is director Vic Armstrong's brother.
A deleted scene involves Severence and Rudy going to Woody Engstrom's ranch to question him about Santee. Rudy almost kills the guard dog for barking at him and Severence is about to kill Woody when other patrol cars arrive, forcing them back down.
The original ending had a scene in the D.A.'s office in which Sheriff Cepeda shows the video of the CCTV footage from Jimmy Shoeshine's warehouse, thus clearing Santee of Deputy Agnos' murder.
The script only called for Santee to kill five henchmen at the warehouse, but for the sake of more action it was changed to dozens and dozens of them.
The U.S. VHS version had its title changed to Army of One so potential renters wouldn't confuse it with the U2 music video of Joshua Tree.