Originally, Roland Sharp (Tommy Lee Jones) was to be an FBI agent working in Virginia, but upon receiving the script, Jones suggested that Texas would be a great location for the film. After the producers arrived, they decided to shoot the movie there, and as a consequence, made the main character a Texas Ranger.
The pizza delivered to Sharp is from Mangia Pizza, an actual pizza chain in Austin. Sharp identifies his pizza as "The Carnivore", which is a real item from Mangia's menu.
Is the first movie allowed to use the full and actual name of the University of Texas at Austin.
The Hex is an actual University of Texas tradition, enacted before the annual Thanksgiving game against Texas A&M University. The Texas A&M Aggies had their own pre-game tradition, the Bonfire, but after a combination of factors caused a collapse in 1999, killing twelve students, the tradition is no longer University-sponsored, it is, however, still organized by the student body, and done off-campus.
No one involved with the film could think of an appropriate ending, until director Stephen Herek came up with one a few months after the rest of the movie was shot.