The scene where Sister Helen was pulled over is based on an incident that happened to Helen Prejean during filming. She thought it was so funny that she asked to have it put into the film.
After being told that she would be played in the film by "a famous actress from Thelma & Louise (1991)", Sister Helen Prejean was introduced to Susan Sarandon and said "Thank God, she's Louise."
The real Sister Helen appears outside the prison during a candlelight vigil scene.
The title "Dead Man Walking" is a slang term used by prison guards when escorting death row prisoners from their cells to the execution chambers.
When director Tim Robbins needed songs written for the film, he simply sent a cut of the film to several noted composers, among them Bruce Springsteen and Steve Earle and asked for a song.
Because Peter Sarsgaard and Missy Yager's brutal rape scene was filmed in the mud, every time they did a new take they had to get up, get showered, get dressed, put new makeup on and do it again. It took all night to film.
In reality, Elmo Patrick Sonnier and Robert Lee Willie, both inmates on whom Sean Penn's character Matthew Poncelet is based on, were executed by the electric chair in Louisiana in 1984; by 1993, Louisiana switched that penalty to lethal injection as the most humane way to execute. Both Tim Robbins and Helen Prejean opted to use lethal injection in the film instead of the electric chair because, according to Prejean's interview, "We don't want to give people the moral (of the most humane death) out whereby people could say 'Oh well, we used to do electrocution but that's too barbaric so now we are humane and inject them'."