Factual error: During the car chase at the beginning, they are chasing a car on Bigelow Blvd., less than a mile from downtown Pittsburgh and we see a big, brick hill they chase down. This hill is actually in Duquesne, PA more than ten miles south east of Pittsburgh. Then as you're watching they are still in the same area as Bigelow Blvd., in the Polish Hill section of Pittsburgh.
Continuity mistake: In the bridge scene, Willis is seen without his crutch as he looks over the bridge at his fallen cousin. They cut to him beside the bridge and he has his crutch.
Continuity mistake: If you watch in the beginning of the movie you will notice during the car chase that various parts of the suspect's car fall off or get torn off and then in other scenes the parts are back on.
Continuity mistake: In the beginning, during the car chase, the Ford LTD they are chasing loses its front bumper, grill and several headlights. It even runs over the bumper causing a large spark display. But in the next shot the car just has lost two headlights.
Revealing mistake: When Hardy goes to check out a victim with Christman, Christman gets in the water to flip the dead woman over and the dead girl blinks her eyes.
Continuity mistake: Immediately after Hardy puts the taser in Jimmy's mouth, Hardy is bald.
Continuity mistake: When Bruce and Sarah stop the drinking kids in the fast speed boat, they confiscate a bottle of scotch. BW opens the bottle to smell it, then the scene goes to the partner and back to him and he UNSCREWS the top and dumps the liquor over the side. He opens the bottle twice.
Revealing mistake: In the scene in the beginning where Jimmy is about to jump from the bridge, he is holding the cables holding the bridge up, which move and flex from his weight. Cables on suspension bridges are extremely tight from the weight and do not move at all if a person pulls them.
Revealing mistake: During the ending boat chase when Jimmy and Tom reach a small waterfall and go over it, their boats ramp up when they go off. There's no reason for them to do this other than stunt ramps put in place. And in several shots they go from nose up to nose down between shots. (01:33:01)
Character mistake: At the start of the car chase scene the dispatcher identifies the stolen car as an '89 Ford, but the Ford LTD Crown Victoria shown in the chase is a 1986 or 1987 model.