The man administering the polygraph test to convict Richard Conte was the inventor of the polygraph or lie detector machine, Leonarde Keeler. He played himself in the movie.
James P. McGuire served as a Technical Advisor on this film. He is the Chicago Times reporter who wrote the articles on which this film is based, and was the basis of the character played by James Stewart.
When McNeal tries to convince Zaleska to take the blame for the murder to exonerate Wiecek, Zaleska asks if he should name "Joe Doakes" as his partner. At the time, Joe Doakes was another name for "Joe Blow" or "John Doe."
The "roundhouse" where Frank Wiecek (Richard Conte) is kept at the Stateville prison was the only remaining panopticon still in use in the United States in the 1990s. It was closed in 2016, but the structure remains, due to its historical significance.
ON SCREEN: "This film was photographed in the State of Illinois, using wherever possible, the actual locales associated with the story." This was the first Hollywood-produced feature film to be shot entirely on-location in Chicago. Many famous landmarks, such as the Chicago Merchandise Mart, Holy Trinity Polish Mission, and the Wrigley Building (of chewing gum fame) on North Michigan Avenue, can be seen throughout the film.