In the closing scene inside the courtroom, Capt. Miller (Lee Marvin) conspicuously comes in and sits down in a chair right next to the door, against the back wall. We see him there in a couple of close-up shots, but in several wide camera shots taken from the front of the courtroom, he is nowhere to be seen.
Near the beginning of the film, Col. Hall, Sr., takes a drink of water and then puts the paper cup down on the water cooler cabinet. In the next shot, as he is walking away, the paper cup is gone.
When Paul Newman and Walter Pidgeon are taking in Pidgeon's car, the latter - who is a colonel in the movie - is wearing a cap that is worn by lower ranking soldiers. Colonels wear caps with yellow braiding (known colloquially in the military as "scrambled eggs".
U.S. Army Officers' uniforms during World War II and the Korean War featured service caps with plain leather visors, regardless of rank. The green "Class A" uniforms adopted by the Army in 1954 included a new service cap with oak leaves ("Scrambled Eggs") embroidered in gold bullion on the visor for field grade and general officers.
On the inside of the door to Captain Hall's hotel room, there is no lock to secure the door from the inside - just a plain door nob.
The two soldiers who load Captain Hall's stretcher into the medical vehicle at the airport have no rank insignia, ribbons, or shoulder patches on their uniforms.
In his closing argument in defense of Captain Hall, the defense attorney mentions that Capt Hall served in two wars, implying service during World War II and the Korean War. But Capt Hall's uniform has ribbons only for the Korean War.
In the scene where Major Moulten first sees Captain Hall's file, as Colonel Hansen leaves the room the shadow of the boom can be seen on the wall above him.