Revealing mistake: During the final conversation between Detective Frazier and Arthur Case, Frazier holds up his hand with the ring on his middle finger. It is pretty obvious that the hand was inserted into the scene in post production; the hand doesn't move in a natural way and simply looks out of place.
Suggested correction: Really? I don't see anything unnatural in the hand's movement at all. Doesn't look at all obvious to me that it was inserted in post-production. After all, Frazier refers to "this ring." They will want it in shot so I'm sure they made sure Washington held it in shot.
Yes, really. Look again. Look at how it moves down and vanishes out of the frame. No human hand moves like that! They didn't have Washington hold it up for the shot and it was inserted later as a pickup shot. See this IMDB goof entry for more details: "During the final conversation between Detective Frazier and Arthur Case..." "a picture of a hand with a ring on the middle finger was inserted into the scene - first moving up into the shot, and then moving down off screen."
Revealing mistake: When Detective Frazier enters the bank and tries to get the jump on Dalton Russell, they get into a struggle and fall down the stairs. As they fall down, look at Detective Frazier's head. It is supposed to be bald, but it suddenly has a full head of hair. It's quite obviously a stunt double.
Revealing mistake: When the policemen are looking at the security camera tapes, it is obvious that one of the infrared rays doesn't come from the lamp. It seems to come about 30 or 50 centimeters from the left.