L.A. Noire's Australian design team occasionally gets it wrong where it comes to the culture and protocols of the U. S. Navy and Marine Corps. Most of these mistakes occur in the wartime flashbacks, but some also appear in the cases The White Shoe Slaying and A Different Kind of War.
- In the inspection flashback at the beginning of A Marriage Made in Heaven, the sergeant refers to Kelso's weapon as a "carbine." In fact it is an M1 Garand rifle, a wholly different weapon from the M1 Carbine. (The sergeant also inspects the bore without opening the action, which is impossible).
- On several occasions Phelps or Kelso addresses a junior Marine as "soldier." This would be appropriate in the U.S. Army, but is not done in the USMC and in most cases would be considered offensive; the correct address is "Marine."
- Kelso is addressed several times as "Sarge." This is doubly incorrect: a) in the U.S. Marines "Sarge" is never acceptable in place of "Sergeant;" and b) Marine NCOs are addressed by their full rank, in Kelso's case "First Sergeant." In informal settings a First Sergeant may (with his consent) be addressed as "Top," which the game does employ correctly.
- At the game's climax Ira Hogeboom salutes Kelso. Saluting, in the U.S. armed forces, is for commissioned and warrant officers; an NCO like 1st Sgt Kelso would not be saluted.
- In The White Shoe Slaying the sailor James Jessop is called an "Able Seaman." Although this rank is found in the British and Australian navies, there is no such rank in the USN. Jessop's sleeve insignia marks him instead as a Boatswain's Mate 3rd Class.