There are plenty of lockers and safes in Resident Evil 2 that you’re going to need to find your way into. One such locker sits on the third floor of the Raccoon City Police Department. You can take the long way by figuring out the puzzles on your own which requires that you find hints in the game, or you can just use this shortcut.
On the third floor there is a locker that can be accessed with a letter-based code. Normally, to get this code you would need to develop film that was found in the Dark Room in the Police Department to uncover the code for the locker. With this guide you can just enter the code to retrieve the contents of this locker.
This lone locker is located on the third floor of the west side of the Raccoon City Police Station and has some extra equipment in there that is protected by a dial lock that has letters on it. Inputting the code DCM will unlock the dial lock and you can pick up the contents of the locker.
The locker code will not change whether you are Claire or Leon, but the contents of the locker will change depending on which character you are and whether you are on their A or B story. For Leon you will get MAG ammo in the 3F Locker.