Factual error: When Quaid eventually catches up with Javier and Matthew Fox, his pistol is a SIG Sauer P229, it can't carry more than 12 rounds in the magazine and can have only 1 in the chamber. However, more than 13 shots are heard firing from it.
Visible crew/equipment: During the car chase the driver's seat on Kent Taylor's car is located on the left side. When he finally gets shot by Barnes and is about to crash, in one of the shots you see a person (in all probability a stuntman) sitting on the right side.
Continuity mistake: Several times when we see what's on Forest Whitaker's camcorder, the elapsed time on the bottom corner shows the same time between shots of the screen.
Other mistake: During the car chase scene, the Opel Astra (blue car) repeatedly collides with other vehicles and objects on the front end, yet the airbags don't deploy.
Other mistake: In the scene where Dennis Quaid fires his SIG-Sauer P229 pistol on the bad guys under the over-pass, he fires 24 shots from a 10-12 round pistol without reloading.
Other mistake: In the last scene under the Highway, when POTUS thanks Barnes for saving his life again and when the camera starts zooming out for the end credits, in the traffic driving above the accident there is a Mexican green taxi cab VW Beetle passing through. But, the whole movie takes place in Spain.
Continuity mistake: At the underpass, when Taylor realizes that Barnes is right behind him on foot, he starts driving away. He's supposed to be speeding away, yet Javier, who is injured, is able to catch up to him on foot with ease.
Factual error: The flag on the outer left of the square keeps changing between the correct flag for Germany (horizontal black, red, yellow) as seen from the aerial shot when the bomb explodes, and a wrong version (horizontal red, yellow, black) which can be seen when Howard Lewis first accesses the square.
Factual error: The engine noises coming from the Chevrolet Astra (blue car) are not coming from any engine in that car. Only the Vauxhall and Opel variants of that model got the high performance petrol turbo engines. It's clearly a Chevrolet from the logo on the front and back of the car.
Deliberate mistake: There are several large security mistakes that were obviously added to the film to move the plot forward. The takeover of "Control" would not happen that way. The Secret Service keeps it in a secret off site location which not even the security detail knows. This location is in some kind of very remote bunker to prevent what happens in the movie. Secondly, when the threat is identified and the switch to the double is made, the President would have been moved to a secure bunker created for the purpose until the threat was dealt with.
Continuity mistake: When Barnes shoots Taylor and Taylor crashes, we then see a shot of Javier on the floor, with his head on his right arm and his left arm beside it. But, when we see Barnes running to the car, Javier's body is at the lower left of the screen and his right arm has moved to his back.
Other mistake: When Barnes first gets into the Chevrolet Astra (blue car), he pursues the police car but never changes from first gear, as he has one hand on the steering wheel and the other holding his phone to his ear. Without a gear change he'd never reach chase speeds, plus the engine strain would be easily heard.
Continuity mistake: When the president is abducted in the ambulance there is a shot of him waking up. In the close-up of his face as he awakes, the metal nose clamps on his plastic oxygen mask are sticking straight out; when the camera angle changes the metal flaps are clamped down on his nose.
Continuity mistake: This movie has a lot of problems with VWs. During the car chase, the blue car passes the red older 80's VW three times between shots. Later in the film, a blue VW rams into the turned over ambulance and in a later shot it is away from the ambulance and undamaged. In another part of the chase scene, the police car passes another blue VW two times.
Deliberate mistake: In the point of view of the Hispanic cop, he is being lead away by a secret service (SS) guy when the cop hears an explosion, he punches the secret service man but before the SS guy can react, the second explosion goes off. In all the other points of view, the first explosion goes off and there is 30-40 seconds of a break before the second explosion goes off. (Its clear the director needed the cop to have the distraction of the first explosion to attempt to get away, but in order for the cop to escape he had the second explosion go off seconds after).
Other mistake: When the Secret Service agents are running after the Spanish cop, they are running and shouting with their weapons waving in the air, yet the group of Spanish police that they pass don't try to challenge them.
Factual error: The movie was supposed to be in Salamanca, Spain, but was shot in Mexico City and Puebla, Mexico. There are constant landmarks that are easily pointed out if you have ever been to Mexico City. Best example: the metro is that of Mexico City. Salamanca doesn't even have a metro. The square where the president is speaking is actually two different locations. The one shot from above is Salamanca but the one close up is from of a museum in Mexico City. You can easily tell these two apart. The tunnel that the president is taken under so he can get into the hotel secretly is a tunnel under the anthropology museum in Mexico City. The chase scene is shot in the streets of Mexico City and Puebla's main square. The green taxi Beetles that are famous in Mexico City can be seen as well, as can the small buses known as "paseros" that are used as public transportation. There are many others as well. One shot of the chase scene was shot on the street I lived on in Mexico City. I watched the whole thing over a five day period.