At the time of filming, author John Grisham had casting approval over all film adaptations of his work, and specified that "no professional child actors in Hollywood" be cast as Mark Sway. He felt that the film wouldn't work with a well-known child actor (sporting a phony accent) in the role and that by casting an unknown in the part (preferably from the Memphis area, where the story is set) the film's credibility wouldn't be compromised. Brad Renfro, a native of Knoxville, Tennessee beat out thousands of actors for the role, including Macaulay Culkin.
At the time of the film, the only prior acting experience Brad Renfro had was a school production about D.A.R.E (Drug and Alcohol Resistance Education). Renfro was arrested and convicted several times for drugs possession prior to his death in 2008.
Joel Schumacher proposed "movie marriage" to Susan Sarandon in the middle of a crowded New York City restaurant during the summer of 1993 in order to convince her to do the movie. She agreed to make the film a few days later.
On his experience working in the film, Anthony Heald said: "The real joy of that situation was getting to work with J.T. Walsh. I had worked with him early in my career (in The Beniker Gang (1985)), and he was drinking at the time, and he was a terrible person to be around. By the time we did The Client (1994), he'd achieved sobriety, and he was the most wonderful, gracious-just a true prince".