Continuity mistake: The amount of damage to the car Kincaid is driving changes drastically between shots. Most noticeable right after he kills the motorcycle driver he does a jump and the hood and headlights break off. It cuts to the others running through the streets for a few seconds, then cuts back to him as he passes under a bridge - the front of the car is almost completely repaired as he is under the bridge, then changes back to damaged after he leaves. (01:30:45)
Continuity mistake: After they break into the old Mercedes by smashing the driver's window, in the scene when they are singing in the car the glass is there, shown by fingerprints. (00:40:00)
Continuity mistake: The 2 main characters are on a roof running from the police. Samuel L Jackson's hands are handcuffed together from a bit earlier on in the film. He jumps off the roof into a bin on the floor but bounces off scaffolding on the way down, there are 2 short but clear shots of his arms wide apart with no chain between the cuffs as he's falling. He lands in the bin and proceeds to get up and out with his hands back cuffed. (00:33:00 - 00:34:00)
Factual error: To my knowledge there is no metro in The Hague. And the only tram in the Hague that goes through a tunnel looks totally different.
Plot hole: In the end Kincaid had to provide evidence against Dukhovich in court to uphold his end of the legally binding agreement from the beginning of the movie. Kincaid directs the courts to a secure website and provides a password to access the site which provides all the evidence needed. Kincaid could've provide that information via phone call or teleconference and never left his jail cell, negating all the unnecessary risk to law enforcement officials and himself.
Other mistake: The airport assassination of Japanese dealer is claimed to be at 300 metres by Kincaid, but the camera shot shows the distance to be at least a mile.
Plot hole: The testimony at the beginning is dismissed as "hearsay" by the judge, but it isn't! It's eyewitness testimony under oath - the judge/jury determine how much weight it has as evidence, not dismiss simply because there's no physical evidence supporting it. The testimony itself is the evidence. Hearsay would be if the witness was testifying that someone else told him what happened. But he's saying he saw this with his own eyes - very different.
Revealing mistake: When Dukhovish lands on the car, the (CGI) smashing of said car is incorrectly timed with the impact.
Continuity mistake: When Mr. Kurosawa gets shot in the plane, the ropes on the left of Bryan are standing until a body guard knocks them down. As they cut to another shot, the ropes are back up. (00:02:55)
Factual error: In the flashback to Whitman's first hit, that of the killer of a pastor, a rook is shown. This bird is not found in the US.
Factual error: There is no Dover-to-Amsterdam ferry service. Such a ferry would quickly cross the English Channel and then sail northeast along the coasts of France, Belgium and the Netherlands (passing The Hague on the way).