Revealing mistake: Before the pimp is shot dead by the police officer, a circular discoloration is visible on the actor's neck, exactly where he is about to be shot.
Continuity mistake: When Early Smith is confronted by a thug with a shotgun in the store, the number on the till is "3.21", but a few shots later changes to "1.79".
Continuity mistake: When the thug with a shotgun tells Early Smith to get down on his knees during the supermarket scene, you can see a female assistant standing next to Early, but when Harry shoots the thug dead, the assistant has disappeared.
Continuity mistake: When Early Smith runs out of the supermarket and shoots one of the three thugs, he lowers his gun after killing the thug. In the next scene, he is holding the gun back in a raised position.
Continuity mistake: When Harry, dressed as an overseas pilot, enters the aeroplane during the hijack scene, one of the hijackers draws his gun right in front of Harry when he says "Good afternoon". In the next scene, the gun is further away from Harry than it was in the previous shot.
Continuity mistake: When Lt. Briggs is being interviewed after the swimming pool massacre, we see a close up of Briggs and there is a man with a moustache next to him. But when we cut to the next shot where Briggs is on television at Carol McCoy's house, the man with a moustache has suddenly disappeared.
Other mistake: In the end credits, Callahan is misspelled as "Calahan". (01:56:50)
Other mistake: Before the shooting, we saw a reflection of the officer in the outside mirror of the limo. The glass is rectangular. The actual mirror of the '73 Cadillac Model 75 had rounded corners.
Revealing mistake: Multiple times during the final chase, tire marks on roadways are visible where multiple takes of the stunts happened.
Factual error: When the pimp murders the hooker in the taxi, he is said to have forced drain cleaner down her throat. However, he uses an aerosol can. You can even hear the metal ball shaking inside of it several times. In the 1970s, drain cleaner did come in metal cans, but what he is using is a spray can of some kind, which drain cleaner did not come in. It is always in liquid form to pour down a drain, spray would not release enough.
Plot hole: Why would a timer be used on a booby trap in the mail box, only that it serves later on to kill Briggs?
Suggested correction: As a back up detonator.
Revealing mistake: After the pool massacre, a police cop walks away from the scene and we see the pool with dead bodies. If you look carefully, you can see a "dead" woman in a red bikini moving her arms as if she was treading water.
Continuity mistake: After one of the cars escapes from Palancio's hideout, we get a view from the driver's seat and Harry fires a bullet into the windscreen and the car is heading directly for an office. In the next scene, the car is much further away from the office than it was in the previous shot.
Other mistake: When Ricca is pushing his way through the crowd, just after a man yells "Ricca, you're a killer" a shot of the crowd shows a sign saying "UP YOUR RICCA" which makes no sense. Surely this sign was meant to say "UP YOURS RICCA." (00:03:50)
Visible crew/equipment: Near the end when Harry is running from the motorcyle cops, he runs up a ramp and through a door. Below the ramp and just above the wooden wall, a camera and crewman wearing a white hat are visible. (01:46:25)
Character mistake: When Harry walks up to look in the car which Ricca and his men were shot in, he places his hands on the driver's side and back seat passenger's side window sill, while the crime scene is being investigated. No senior Inspector like Harry would do this. (00:09:40)
Other mistake: In the scene where the mob boss gets interviewed in the garden atrium after being freed, the news media pushes up to get really close to the podium. Note that the first reporter, dressed like Gilligan, trips and almost falls into the podium. He catches himself but has to keep his head down during the rest of the shot.
