Factual error: At the end when they are loading Dewey into the ambulance on the stretcher, it is standard procedure to put the patient neck brace when they receive any type of unknown injuries (stab wounds) to their back as Dewey did - it was notably absent.
Factual error: The actual Tsavo lions responsible for the killings had no manes - see for yourself; they are on display at the Field Museum in Chicago. [The filmmakers employed artistic license in using maned lions. They were also certain to include - at the very end of the movie - footage of the real Tsavo man eaters, as they appear in the Field Museum.]
Factual error: The Abilene, Texas courthouse should read Taylor County Courthouse, being that Abilene is the county seat of Taylor County, Texas. All Texas courthouses are named by the county they are in.
Factual error: The geography throughout the film is all wrong. The setting is in Pennsylvania, near Pittsburgh. The driving times between there and Williamsport are extremely under-estimated. Most egregious is the river structure. The body is found in the river near Sunbury. Not possible from a site in Western PA. Basically all relationships between actual towns/cities mentioned are totally wrong.
Factual error: A vinyl knife is present among other tools of torture during the 1700's sequence, but vinyl flooring did not come into the commercial market until the mid twentieth century.
Factual error: As Burt is driving, he is producing a video diary. He indicates it is 1900 hours (7PM) on May 14th, and yet it is pitch black outside. Nowhere in Mexico would the sun have set by 7pm in May.