During the montage showing John Doe Clubs gaining in popularity, closeups of a map are shown with flags being pinned up for every new club. At the end of the montage, the camera pulls back to show a map of the entire US. However, the final map has substantially fewer flags pinned to it than what was shown during the closeups.
When Ann is struggling to write John Doe's radio speech, she balls up one draft and throws the paper on the floor in disgust. The dog picks up the crumpled paper and approaches the apparently empty wastebasket. After the cut, when the dog drops the paper into the wastebasket, the wastebasket is full.
After "John Doe" intrudes on D. B. Norton's dinner party and tells him off, Norton calls his newspaper and orders a special edition which will reveal Doe as a fraud. Doe takes a cab from Norton's house directly to the convention hall. Within minutes of his arrival there, a horde of newsboys appear with copies of the newspaper. It would be impossible to print an extra edition in such a short period of time.
When Henry is telling John about Morton's plans for the John Doe clubs, he lights a match but holds it an inch above the cigarette that he suppose to light it with. At the end of the scene, Henry presses the end of the cigarette into a plate to extinguish it, but the cigarette at this point is no longer burning and the end is already bent over showing that it had already been pressed into the plate in an early take.