Years ago police officers used a series of codes to speed up communication over the radio. Commonly referred to as 10-codes this system was developed in the 1930’s by the Illinois State Police. These codes were developed due to quirks in early police radios where the first syllable of words spoke was often times cut off. By saying “ten” then the actual message the important part of the message was never cut off.
The initial list of 10-codes was limited. As other departments adopted the idea additional codes were added to the list. Meaning that in various regions of the country there are variations to what codes stand for.
After the events of September 11, 2001, and the 2005’s Hurrican Katrina it was recommended to phase out the use of 10-codes. At both events, responders had a hard time communicating with each other due to using codes versus plain English. The recommendation in many jurisdictions now is to just talk in a normal talk when on the radio. Some towns and some officers still will slip into 10-codes.
Below are a common list of 10-codes. Keep in mind some cities might have a variation on this list.
10-0 – Person is dangerous, use caution
10-1 – Radio reception is bad
10-2 – Radio reception is good (can also be used for I am OK)
10-3 – Hold radio traffic
10-4 – I acknowledge, or I agree
10-5 – Relay message
10-6 – Busy
10-7 – Out of Service (often use as meal break)
10-8 – Back in Service
10-9 – Please repeat the last transmission
10-10 – Fight in progress
10-11 – Dog
10-12 – Standby
10-13 – Weather Report
10-14 – Suspicious person
10-15 – Disturbance
10-16 – Domestic Violence
10-17 – Complainant
10-18 – Quickly or Urgently
10-19 – Return to [Location]
10-20 – Location
10-21 – Call on Phone
10-22 – Disregard
10-23 – Arrived on Scene
10-24 – Assignment Complete
10-25 – Report to [Location]
10-26 – Detaining a subject
10-27 – Driver License Information check
10-28 – Car license information check
10-29 – Check for warrants
10-30 – Unnecessary use of radio (telling someone to shut up)
10-31 – Crime in progress
10-32 – Person with gun (Also used to alert a partner when someone sees a gun hidden)
10-33 – Emergency
10-34 – Riot
10-35 – Crime Alert
10-36 – Time Check
10-37 – Suspicious Vehicle
10-38 – Stopping suspicious vehicle
10-39 – use lights and siren
10-40 – don’t use lights or siren
10-41 – starting shift
10-42 – end of shift
10-43 – FYI
10-44 – Request permission to leave
10-45 – Animal
10-46 – Assist a Motorist
10-47 – Emergency road repair
10-48 – Traffic issue
10-49 – Traffic light out
10-50 – traffic crash
10-51 – Tow truck
10-52 – Ambulance
10-53 – Roadblock
10-54 – Livestock on road
10-55 – Drunk Driver
10-56 – Drunk person
10-57 – Hit and Run crash
10-58 – Traffic Direction
10-59 – Escort
10-60 – In the general area
10-61 – have a person close to me
10-62 – Reply to message
10-63 – Make a written copy
10-64 – Message for local information (be on the lookout in district)
10-65 – Message for area information (be on the lookout for anyplace)
10-66 – Message cancel
10-67 – Stop and be ready for message
10-68 – Dispatch information
10-69 – Message understood
10-70 – Fire
10-71 – Nature of Fire
10-72 – Progress on Firefighting
10-73 – Smoke alarm
10-74 – Negative
10-75 – Meeting with
10-76 – En Route to
10-77 – ETA
10-78 – Need Help (also used as officer in distress)
10-79 – Call Coroner
10-80 – Chase or pursuit
10-81 – Breathalyzer
10-82 – Hotel
10-83 – School Cross duty
10-84 – Advise ETA
10-85 – Delayed
10-86 – Operator on Duty (typically asking for certified Breathalyzer technician)
10-87 – Pick up item
10-88 – Request for phone number
10-89 – Bomb
10-90 – Bank alarm
10-91 – Pick up person
10-92 – Parking issue
10-93 – Blockade
10-94 – Drag Racing
10-95 – Person under arrest
10-96 – Person acting Crazy
10-97 – Status Check
10-98 – jail or prison breakout
10-99 – person is wanted
10-100 – Bathroom break