Continuity: When Frank Ochoa is interviewing the mugging victim after Paul Kersey shoots dead the three thugs in the alley, the victim's hat appears and disappears between shots.
Continuity: Kersey's first shooting victim is hit in the abdomen, but a police investigator at the crime scene the next morning refers to a bullet hole in his chest.
Continuity: When Kersey is about to be robbed in the subway wagon, you can see a big brown shopping bag. In the next scene, when he leaves the wagon it is gone. It is the same shopping bag which is later related to at the police station.
Continuity: The bloody rag Ochoa gets out of Kersey's trash can is not the same one Kersey used on his wound. Kersey’s back was stained with blood from the stabbing, and that rag got soaked with blood. Yet the rag Ochoa pulls out of the garbage is not stained with blood, there's just a small spot of it.
Crew or equipment visible: When Kersey chases the last robber at the end of the film, you can clearly see spotlights in the background.
Crew or equipment visible: When Paul and son-in-law looks out the in-house window at the hospital we see them through the glass. In the reflection there's a barely visible large black square. When the camera dollies left the square follows, indicating that the square is there to disguise an all too recognizable camera silhouette.
Continuity: In the beginning when Mrs. Kersey and daughter in-law leave store, they walk past 2 guys carrying a couch across the side walk. In the next shot, the two women are some distance past the movers but the couch is still being carried across the sidewalk.
Factual errors: In the scene where Ames Jainchill (Stuart Margolin) and Paul Kersey (Charles Bronson) are at the gun club, Ames hands Paul a blackpowder pistol stating it is an '1842'. Ames is totally incorrect. Paul takes it and lifts the gun to shoot it down range, it is clearly a Remington model 1858 blackpowder pistol based on the Fordyce Beals patent of September 14, 1858 (Patent 21,748), produced by Remington Arms from 1862-1875.