Factual error: When Harry is confronting the bank robber and the robber says he has to know if Harry had any shots left, Harry cocks the hammer which rotates the cylinder. If you watch closely when he pulls the trigger the cylinder rotates again. This can happen only when the trigger is pulled in double action mode (hammer down). (00:14:00)
Factual error: The "B" train which he is chasing normally runs on the right most track (there are 3 tracks on this particular line). The middle one is never used except for out of service trains. Most of the train stations on that line service the right or left track, not the middle one.
Factual error: The calendar in the police office indicates Tuesday January 27th and Thursday January 29th. That was in 1970, but this story takes place in 1971.
Factual error: Raquel Welch is shown to have modern tooth fillings during the rape scene.