The attorney mentions that there are 21 bullet wounds in Bubba's body, but the count of the shots that the men fire is only 14.
The position of Hazelrigg's right hand when he tries to guess Marylee's costume is off.
When Hazelrigg is getting a glass of punch at the Halloween party, a woman pours a glass of "fixed" punch for him. Realizing her mistake because Hazelrigg, ostensibly, does not drink, she sets the glass aside. The glass disappears and reappears from shot to shot several times from this point on.
Mrs. Ritter hears noises coming from the kitchen and goes to lock a screen door that has been opening and closing due to the wind. She clearly locks both the screen door and then the kitchen door before lighting the gas stove and putting the kettle on to boil water. After Hazelrigg's intrusion causes her to have a massive heart attack and he realizes what he has done, he flees to the kitchen and unlocks the kitchen door to try to escape, but is frightened when the kettle begins to sound on the stove. After he removes the kettle and turns the stove off, he gets the idea to turn the gas back on to blow up the house so that he can cover his tracks. When he goes to leave the house, the screen door is magically unlocked.
They saw the spot in the wheat field where the scarecrow was, but corn went in the silo. Wheat gets harvested long before corn does.
When the tractor is chasing the postman at the end, it runs over pumpkins in the field and smashes them. The smashed pumpkins have no insides, revealing them to be props.
When the postman is stabbed to death at the end, he grabs his gut and looks down at himself. There are no holes in his shirt.
When Bubba is hiding in the Scarecrow costume, it is obviously a real scarecrow in some longer shots, as it has less body mass than Bubba does.
Mrs. Ritter is still clearly breathing when Otis realizes she is dead.
When Harliss approaches the cross where scarecrow was hanging in his field, there is light around it even though the rest of the field is dark, clearly an artificial light for the set.
During the final act, Hazelrigg is running away from the seemingly empty tractor; however, just before the tractor stops you can clearly see the shape of a man, who appears to be wearing blue overalls, operating the tractor.
As Philby approaches the grain silo with something to hit with, a shadow of the cameraman is seen on the side of the silo. It then goes down.