Police dispatchers will use the codes listed below to substitute an action with a “code” rather than speaking the literal translation of said action. It’s much easier and more clear on a police radio to say “Code 4” rather than ‘No further assistance required’, especially when radio transmissions can be garbled or hard to understand.
I’m pretty sure most police departments still use these codes. I know they do state-wide in Colorado, however, I have yet to hear a Code 9, 10 or 11.
Code 1: Attention all units
Code 2: Urgent – no light or siren
Code 3: Use lights and siren
Code 4: No further assistance needed
Code 5: Stakeout
Code 6: Stay out of area
Code 7: Meal break
Code 8: Restroom break
Code 9: Summer uniform
Code 10: SWAT pre-call up
Code 11: SWAT Call up
Code 37: Subject/Property wanted