As suspect Blank (Dukes) is fleeing from Detective Delaney (Sinatra), he goes around a corner carrying an ice ax in his right hand but he was not holding it when approaching the corner nor right after heading toward the camera.
Even though the murder was committed prior to DNA evidence was in use, it is totally inaccurate that gloves would not be worn when a murder victim is being first examined as was the case at the beginning of the movie. The detective and medical examiner both would have been wearing gloves so as not to compromise any evidence.
Sinatra may have left the key in to add to the call of being threatened and then shot thru the head! the key in the lock would have supported a break in! Seems like a smart move.
When Detective Delaney (Sinatra) enters the apartment of suspect Blank (Dukes), he leaves the home-made key in the lock.
Boom mic appears in lower left-hand corner behind Detective Delaney (Sinatra) while talking Blank (Dukes) out of the bottom of his closet.
At the beginning of the film, the endotracheal (breathing) tube being used on Barbara is not taped in place or secured in any other manner. Also, the x-rays displayed, correctly an IVP (intravenous pyelogram), show a non-functioning left kidney, but Barbara is positioned for surgery on her right kidney.
Blank tells the police that his address is 525 W. 83rd St. However, earlier, the number "300" is seen on a doormat at the entrance to his building. (The address where the scenes were filmed is indeed at 300 E. 74th St.)