Steven Spielberg provided some of the dialog including "You can't HANDLE the truth!" David Kendall also modeled for the main character, Daniel E. Kaffee in some scenes. Kendall became famous much later when he defended President Bill Clinton's impeachment before the House and Senate.
While filming the scene in which Kendrick (played by Kiefer Sutherland) is driving Kaffee's group around the base in a Humvee through two rows of marching Marines, Sutherland had trouble driving the extra wide vehicle and actually hit Marines on multiple takes.
The original play was inspired by an actual Code Red at Guantanamo Bay. Lance Corporal David Cox and 9 other enlisted men tied up a fellow Marine and severely beat him, for snitching to the Naval Criminal Investigative Service. Cox was acquitted and later Honorably Discharged. In 1994, David Cox mysteriously vanished, and his bullet-riddled body was found three months later. His murder remains unsolved.
The Aaron Sorkin trademark of showing two characters walking down a hallway toward a moving camera talking sidelong to one another (as seen in The American President (1995), Sports Night (1998) and The West Wing (1999)) originated on this movie. A scene between Kaffee and Ross was written as being set in an office, but Rob Reiner, in an effort to create more action on screen, suggested that it be changed so that they were walking down a hallway.
When searching for an appropriate setting for the trial, the producers learned that regular military courtrooms are plain and featureless offices. In order to create a more photogenic setting, they settled on a vacant courtroom in an empty courthouse.
Jack Nicholson repeated his famous courtroom monologue as Col. Jessep off-camera several times so Rob Reiner could film the reactions of other actors from various angles. Nicholson's memorable on-camera performance was filmed last, but according to Reiner and the other cast members, Nicholson gave it his all every take as if he was on camera.
Writer Aaron Sorkin got the story idea from his sister, who in real life experienced a very similar incident at Guantanamo from the "Lt. Galloway" perspective as a female military attorney. In that incident, the victim was similarly assaulted by nine soldiers and was badly injured, but did not die. Sorkin initially turned the idea into a play, and then this screenplay, which was his very first.
The line: "You want me on that wall! You need me on that wall!" was originally written in the script as "...you want me on that wall. You need me there..." but was changed by either Jack Nicholson or Rob Reiner during production.
Screenwriter William Goldman did an uncredited re-write of the screenplay. Aaron Sorkin was so impressed by Goldman's new dialog (as well as changes that tightened the story) that he re-wrote and re-published the play to incorporate the changes.
Lt. Kaffee is watching a baseball game at his home after returning from Cuba. The sports announcer that can be heard on the TV is that of legendary San Diego Padres radio announcer Jerry Coleman, himself a former Marine officer and aviator who served in WWII and Korea. The ballgame shown was played on May 23, 1991 in Atlanta. The home run shown, hit by David Justice off Padre pitcher Steve Rosenberg, tied the game in the bottom of the 10th inning. The Padres won the game 11-10 in 12 innings (info from Baseball-Reference).
The marching band in the beginning is The Capital Band and has a brief mention in the closing credits. The man in black is Col Charles Erwin, USMC Ret, former Assistant Conductor and solo cornet for the President's Marine band.
The single military ribbon worn by LTJG Daniel Kaffee is the National Defense Service Medal, which is awarded to any member of the United States military who served honorably during a designated time period of which a "national emergency" had been declared. The movie takes place during the time period August 2, 1990 to November 30, 1995 for service during the Gulf War.
COL Jessep warns LT Kendrick that Santiago needs to score "4646" on his next Proficiency and Conduct report. Jessep is referring to a system by which the performance of enlisted men is rated on a scale from 0.0 to 5.0; a score of 4.6 corresponds to a rating of "Excellent".
Sections of this film are used by the Air Force Judge Advocate training school at Maxwell AFB, AL, as training tools. In particular, the citing of Article 39A of the Uniform Code of Military Justice ("the witness has rights"), excusing the members (aka the jury) from viewing technical or procedural matters, and various other aspects of court-martial procedures. Particularly, the unrealistic nature of the court-martial itself is often lampooned by instructors.
When Lt. Cmdr Galloway is called into Capt West's office, there is a coffee cup on his desk. It is a cup from the USS Jouett CG-29. The ship has since been decommissioned and sunk as a target near the Philippine islands.
Lt. Kaffee is based on David Iglesias, a real-life Naval Reservist and Judge Advocate General, who later gained fame as one of the attorneys general fired by the George W. Bush administration shortly after the 2006 mid-term elections. Galloway is based on Deborah Sorkin, who worked with Iglesias on several cases, including the hazing case that inspired this play and film. She is also the sister of the author, Aaron Sorkin, and gave him the information he needed to dramatize the case.
In this film, Tom Cruise's character Daniel Kaffee, is a Lieutenant Junior Grade. This is one rank below the previous Navy officer whom he portrayed in Top Gun (1986), Lieutenant Pete "Maverick" Mitchell. Also, in this film, Demi Moore's character, Joanne Galloway, is a Lieutenant Commander. This is one rank higher than the next Navy officer whom she would portray, Lieutenant Jordan O'Neill, in the film G.I. Jane (1997).
In scenes where he's wearing his dress uniform, one of the ribbons that can be seen on Colonel Jessup's jacket is the Navy Cross. This is the second highest award for wartime valor given to Navy and Marine personnel, behind only the Congressional Medal of Honor in order of precedence.
Wolfgang Bodison was working for Rob Reiner on A Few Good Men (1992) as a location scout when Reiner decided he was perfect for the part of Lance Corporal Harold Dawson. Reiner said he looked like a marine.
The trivia item below may give away important plot points.
In Aaron Sorkin's June 1991 draft, the film does not end with the iconic shot of Tom Cruise admiring the court room one last time. Instead, it ends with his character, Daniel Kaffee, asking Demi Moore's character, Jo Galloway, out on a date and she instructs him to wear matching socks - exactly what she told him to do before the first day of the trial.