Character mistake: In London when Bourne runs down the escalators the camera follows him from behind. All the people act normal except for a man that turns around right when the camera man is about to pass by next to him.
Character mistake: When Simon Ross shows Interpol a picture of Jason and Marie together in the coffee shop to Ray Willis the photo shows Marie with a dark bob cut. She didn't get that cut until they were "on the run" and no agency would have had her looking like that. (00:06:48)
Character mistake: As Jason reads the Guardian Newspaper, he finds an article about himself entitled, "Who is Jason Bourne?" The caption for the article reads, "His code name is Jason Bourne, but he had many identities, each one seemingly more deadly then the next," instead of "more deadly than the next." (00:12:50)
Answer: Knowing Bourne, he must have had a keycard on his person. Remember that Landy guided Bourne back to the CIA New York Headquarters; she could have easily slipped a keycard in the Taxi Cab when Bourne was being picked up at the airport. All he would have to do then is avoid being detected by using the fire exits (hence going through the back).
Jason Riley