When Dana Andrews is staging the murder scene after Stevens' death, he is gloveless. A few seconds later he has gloves on both hands.
As Scalise and his gang are descending in the garage elevator, Dixon throws the switch stopping the elevator between floors four and five (according to the dial above the elevator). However, in the next shot inside the elevator, the inner door is marked "7", indicating that the car has stopped on the seventh floor.
By the sign near the door, Willie goes into the "45th Street Hotel" early in the film, where Tommy has his floating crap game. However, after the incident there, Mark is dispatched to the "43rd Street Hotel".
In the opening sequence, the police dispatcher is heard on the car radio. The words spoken by the dispatcher, announcing two incidents, are lifted directly from the 1949 Procedures Manual of the New York City Police Department, where they are given as examples of the correct radio method. Only the time of day was changed to agree with the scene, but the addresses, incidents, car numbers, and dispatcher number are verbatim from the manual.
Although Otto Preminger places and moves his camera with great skill in this film, his camera is set up on Dana Andrews right in-between him and suspect Craig Stevens. Stevens' first punch misses Andrews' chin by at least a foot.
Detective Dixon knocks down Ken Paine (Craig Stevens). Paine hits the ground and is dead. Dixon (Dana Andrews) gets on one knee and starts slapping Paine's face back and forth, and Paine's head rolls side to side with each slap. However, after Dixon stops slapping, Paine's head rolls back to the other side. Corpses don't do that.
When the car Dixon is riding in pulls onto (and off) the garage elevator on the way to Scalise's hide-out, the camera shakes violently for a few seconds.
At Martha's Cafe, after Martha lights the candle, she tosses the match but it misses the ashtray--the match lays on the tablecloth to the right. In the sequence that follows, the match is missing.