The "executioner" depicted in the movie is a uniformed corrections officer and is visible to the condemned in the death chamber. According to the Florida Corrections Commision Report, "The executioner is a private citizen..." "The executioner is present in the death chamber behind a screen."
The executioner is shown giving the condemned one application of lethal current. According to Florida procedures, current is applied three times.
Early on in the movie Ted attacks a woman with a hammer handle. As he grabs her, the handle - which is supposed to be hard wood - bends at the base to reveal that it is rubber.
The film changes the names of the victims out of respect. However, at the end it plays an actual clip which reveals the real name of a victim. (Bundy's last one, Kimberly Leach, named "Suzanne" in the film.)
Ted is having sex with Lee tied up, as he is performing and the camera pulls back, Lee's underwear is visible.
When Ted is in the grocery store near the beginning of the movie, we see a cap gun on the racks. The gun has an orange cap on the end of the barrel, a safety feature not introduced until the late '80s.
When Bundy is bludgeoning the woman with a rock, his pants are unbuckled and he's wearing Fruit of the Loom underwear, with the letters "FTL" inscribed on the band. Fruit of the Loom didn't start using the FTL acronym on their garments until 1998.
When Ted is in the bar the music playing as if from the future. Break beats and "acid" sound are from mid 90's, but everything is happening in mid 70's.