When Perry is speeding in reverse from the roadblock on the rioting streets, he rams an upside down car, crushing the rear right-hand side of the car. Later, the rear of the car is undamaged.
After Bobby shoots an "innocent" suspect, the gun Eldon handed the suspect to make it look like self defense is clearly seen lying on the ground before him on ground views but not on helicopter views.
During the opening scene, the car's rear-view mirror suddenly disappears between shots.
When Perry goes to 12657 Juliet, the number of shotgun shells remaining in the storage clip on his shotgun after he loads it alternates between two and three between shots.
Maniac's visor falls off his head before Bobby puts him in the car, in the next shot, the visor is back on his head.
Its mentioned that Ving Rhames' character Chief Holland has taken a civil service test for the chief of police for Cleveland police dept. The Chief of police is not covered under civil service law, so Holland would have not taken a test he would have simply just interviewed for the position.
During the sex scene between the young detective and Beth, their underwear is showing under the covers.
Assistant Chief Holland is wearing his rank insignia upside down during Detective Keough's Officer-Involved-Shooting Board. He wears 3 stars on each collar; one point of each star should be pointed up (towards his neck) however he is wearing them pointed down.
Many vehicles that weren't around until long after 1992 are clearly visible in most exterior scenes.
During one of the riot scenes, a rioter can be seen pushing a shopping cart with Super Soaker brand water guns in it. This particular model of Super Soaker did not exist in 1992.