Factual error: When Baldwin is in the old Caddy convertible driving alongside the train, he sets the cruise control so that he can jump into the train. There are three problems with this. I seriously doubt a Caddy that old, it looked like early 70s, would have cruise control, but they were luxury cars, so it is possible. They show a shot of him setting the cruise control, and it is on a modern-style control stalk, very typical to late 80s and early 90s GM cars. Since the ground along a railroad track is not pavement, it would be very bumpy and uneven, and virtually impossible for the cruise control to keep the car going whatever speed he wanted it to go, going over dumps and holes like that.
Factual error: When the hovercraft is stopped after Jackie cuts the side open, it isn't slanted to one side(from the outside view), it is straight.
Suggested correction: It is slightly slanted... it's just hard to see with the camera angles, since it's mostly shot from the side once it crashes.
Factual error: During the scene where Navajas is throwing knives at El Mariachi and then the Bucho gang in the limo, he slides down in front of the car. The license plate simply says "Mexico" under the serial. Actual Mexican plates of the time period in the movie use the official state abbreviation followed by MEX to identify the state of issue. For example, JAL MEX for Jalisco, which is where the JWF685 serial seen on the plate would have been issued.
Factual error: At the end when the oil in the cavern is burning there is no sign of smoke. With a fire as large as it appears to be, everyone in there should be choking to death, yet they don't even seem the least bit bothered. Forest Whitaker should have also been roasting over the flames, yet he is unscathed.
Factual error: The morning after Katherine found out that Max was cheating on her, while Max is getting dressed for work he dumps out a box of aluminium cased ammo on the dresser, which was unavailable until the early 80's. (01:18:05)
Factual error: There is a scene where the teenage girl says "She lets me drive her car and I don't even have my Learner's Permit yet." The setting is in New Hampshire. New Hampshire does not issue Learner's Permits. NH law is that the driver must be at least 15 1/2 years of age and accompanied by a licensed driver who is at least 25. You can then get a license at 16.
Factual error: There is absolutely no way that Internal Affairs would have any authority or power to shut down an entire police force because of stolen drugs. As in the plot of the film, that type of decision would be decided by the city council on a vote and approved by the mayor. In any case, an extensive investigation would take place and the culprits would be arrested and prosecuted. No police force would be disbanded because of this absolutely fictional scenario.
Factual error: When Helen is launching the video that shows the girl turning into worms (the killer's next victim later found at the dumpster), typing "tomorrow.avi" as she does would have returned an error in Linux. She should have typed "call tomorrow.avi" to launch the video. (00:43:00 - 00:44:00)