Real residents of Carthage, Texas who knew the real Bernie Tiede and Marjorie Nugent appear in the film providing commentary on the events.
Jack Black met with the real Bernie Tiede in Telford Unit State Prison. Shirley MacLaine also spoke with Tiede over the phone.
The owners of the Hawthorn Funeral Home in Carthage, Texas, where Bernie Tiede met Marjorie Nugent, refused to allow the film to use the name of the funeral home.
Matthew McConaughey's mother, Kay McConaughey, makes a cameo in the film as one of the residents of the town.
The film is based on a 1998 article in Texas Monthly which was written by Skip Hollandsworth.
Bernie Tiede lived in director Richard Linklater's garage apartment between 2014 and 2016.
Actress Margaret Bowman, who played Mrs. Nugent's sister, played Matthew McConaughey's mother when both appeared in a reenactment of a crime on "Unsolved Mysteries" in 1992.
Bernie Tiede is from Abilene, Texas where he graduated from Cooper High School. Upon graduation he worked at Norths Funeral Home before leaving Abilene.
Carthage's local radio station has the call letters KGAS. Kyle Gass (K. Gas) is a close friend and fellow musician with lead actor Jack Black.
There are several scenes that show Bernie (Jack Black) in rehearsals for different community theater musicals. He sings the duet "I've Never Been in Love Before", which ends the first act of Guys and Dolls; he also sings "Seventy-six Trombones" from The Music Man.
Parts of the movie such as the airport and BBQ restaurant were filmed in Smithville. This is the same place that Hope Floats with Sandra Bullock was filmed.
Richard Robicheaux (Lloyd Hornbuckle) went to Stephen F. Austin University, just a few miles from Carthage, TX. He also went to high school at Channelview, TX, which is about 175 miles away.
Matthew McConaughey, who plays District Attorney Danny Buck Davidson, was born and raised in Texas, where the film takes place.
Jack Black and Matthew McConaughey previously starred together in "Tropic Thunder" (2008).