Continuity mistake: In the scene outside the hospital, after Nick Poole has been shot, Remy Bressant picks up the bottle of liquor, which was capped by Patrick Kenzie and drinks straight from the bottle. The bottle has mysteriously uncapped itself.
Visible crew/equipment: During a shot of two of the bar patrons, a man runs past them in the background. The man is director Ben Affleck. He didn't realize it was himself until after he chose to include the shot in the film. (00:16:40)
Continuity mistake: The scene with the two young detectives driving the crack mother of the missing child starts out with no rear view mirror on the windshield and no one wearing their seat belts. Then the driver has his seat belt on for one shot then it is gone again. The rear view mirror appears back on the window at the end of the movie.
Continuity mistake: At the beginning of the film when Patrick and Angie go to see Helene McCready (the mother of the missing child), When Bea takes the couple out of the room to talk to them, her arms are folded differently from shot to shot.
Plot hole: When Detective Broussard is killed and Patrick was being interviewed by police (dressed in a white shirt), the interviewing police detective say "a couple of nights ago you were at the quarry." In fact it was months before when they were trying negotiate the release of Amanda at the quarry. It unravels the entire movie.
Other mistake: Near the end of the film, when Jack Doyle is being arrested, the Mass. State Police troopers' badges and shoulder patches are not what is actually worn by this police department, although the remainder of the uniform appears to be accurate.
Chosen answer: Even though he executes an unarmed man, it is doubtful given the circumstances that he would be investigated with much fervor for his actions. One police officer has just been shot and killed so Patrick's actions could easily be described as self-defense in the eyes of an investigator. Anyone making a claim to the contrary would risk having to stand up for a child murdering cop killer.
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