When Dillinger and his girlfriend sit in the Biograph theatre at the end of the picture, there is a lady in the row behind them, always seen between their heads. First it is one with a fair hat, then another one with black hair and glittering stuff in it, then again the one with the fair hat.
At the end of the movie, when the three FBI men arrive outside the movie theater, two of them are carrying Thompson submachine guns, but when they shoot it out with Dillinger, all three have pistols.
Waiter brings three beers to Dillinger and Helen's table. Dillinger tells the waiter to sit down. At that time the waiter has his towel under his right arm. Next shot of him in the act of sitting he has the towel in his left hand. Third shot of him seated the towel is under his right arm again.
In a movie show at the beginning the film, there is a car, lettered with "First National Bank" drawn out of a swamp that's said to have been used in a hold-up. Later in the movie we learn that his First National heist was on a train, not a car.
When Dillinger invites the waiter to have a beer with him and then tells Helen to wait outside, he slides her beer over to the waiter. The mug is full when he slides it over but when Helen left the table the mug was partly empty.
When Dillinger and the gang pull the mail train job, the train shown is a Southern Pacific "Daylight," easily recognized by the scarlet and orange paint scheme. Daylights ran from Seattle to Los Angeles, not in the Midwest.
When scenes are set in Chicago, the uniformed Police are shown as wearing shield type badges on their coats. The Chicago Police and the old (now disbanded) Chicago Park District Police had Stars, rather than Shields. In those days it was a six pointed star; but ever since the mid 1950's it has been five pointed.
The calendar in the apartment goes from Fri Dec 24 1933 to Tue Jul 22 1934, but both of these dates fell on Sundays.
When Dillinger holds up the theater, the two film titles on the theater sign are the Monogram pictures, The Legion of Missing Men (1937) and The Unknown Guest (1943), each of which was released years after Dillinger's death.
There are numerous mid- to late-1930's automobiles used in the film, a 1939 Ford and a 1940 Lincoln coupe, among others.
All of the women's hairstyles and both men's and women's clothing is strictly in the style of 1945, even though the story is taking place in the early 1930s, when they were considerably different.
When Kirk Otto introduces Dillinger to Mr. and Mrs. Otto, saying "Call her Mom. I call that guy Pop," his lip movement doesn't match what is being said.
Dillinger's first crime wave in the state of Indiana shows a map of western Los Angeles County. The towns of El Segundo and Hawthorne are easily readable on the map.
This film, which is set primarily in the Midwest, was clearly shot in California. For example, there are mountains visible about 15 minutes in when John goes to the cement factory.
When Dillinger and Helen are walking to the movie theatre (about 1:06 into the film), the shadow of the boom mike can be seen on the brick wall above the children watching the man with the monkey.