Published: April 21, 2008 10:04 am         

The ABC’s and 123’s of Law Enforcement Lingo

Have you ever overheard a conversation between a law enforcement officer and dispatch personnel? If you answered yes, have you ever wondered what they were discussing with a 10-this and a 10-that?

Ten-codes were developed in the 1940s, at a time when police radio channels were limited, to reduce use of speech on the radio, according to experts at Officer.com. Some believe it originated with a man named Charles Hopper, a communications director with the Illinois State Police who was involved in radio for many years and saw a need to abbreviate radio transmissions on state police bands.

Often used by law enforcement personnel, as well as other groups, the ten-codes represent everyday phrases in voice communication. The codes, which were expanded by the Association of Public-Safety Communications Officials during 1974, allow for brevity and standardization of message traffic.



• 10-0 —Caution

• 10-1 —Unable to copy, change location

• 10-2 — Signal good

• 10-3 — Stop transmitting

• 10-4 — Acknowledgment (OK)

• 10-5 — Relay

• 10-6 —Busy, stand by unless urgent

• 10-7 —Out of service

• 10-8 — In service

• 10-9 — Repeat

• 10-10 — Fight in progress

• 10-11 — Dog case

• 10-12 — Stand by (stop)

• 10-13 — Weather or road report

• 10-14 — Prowler report

• 10-15 — Civil disturbance

• 10-16 — Domestic disturbance

• 10-17 — Meet complainant

• 10-18 — Quickly

• 10-19 — Return to ...

• 10-20 — Location

• 10-21 — Call ... by telephone

• 10-22 — Disregard

• 10-23 — Arrived at scene

• 10-24 — Assignment completed

• 10-25 — Report in person (meet)

• 10-26 —Detaining subject, expedite

• 10-27 — Driver’s license information

• 10-28 — Vehicle registration information

• 10-29 — Check for wanted

• 10-30 — Unnecessary use of radio

• 10-31 — Crime in progress

• 10-32 — Man with gun

• 10-33 — Emergency

• 10-34 — Riot

• 10-35 — Major crime alert

• 10-36 — Correct time

• 10-37 — (Investigate) suspicious vehicle

• 10-38 — Stopping suspicious vehicle

• 10-39 — Urgent, use light and siren

• 10-40 — Silent run, no light or siren

• 10-41 — Beginning tour of duty

• 10-42 — Ending tour of duty

• 10-43 — Information

• 10-44 — Permission to leave ... for ...

• 10-45 — Animal carcass at ...

• 10-46 — Assist motorist

• 10-47 — Emergency road repair at ...

• 10-48 — Traffic standard repair at ...

• 10-49 — Traffic light out at ...

• 10-50 — Accident (fatal, personal injury, property damage)

• 10-51 — Wrecker needed

• 10-52 — Ambulance needed

• 10-53 — Road blocked at ...

• 10-54 — Livestock on highway

• 10-55 — Suspected DUI

• 10-56 — Intoxicated pedestrian

• 10-57 — Hit and run (fatal, personal injury, property damage)

• 10-58 — Direct traffic

• 10-59 — Convoy or escort

• 10-60 — Squad in vicinity

• 10-61 — Isolate self for message

• 10-62 — Reply to message

• 10-63 — Prepare to make written copy

• 10-64 — Message for local delivery

• 10-65 — Net message assignment

• 10-66 — Message cancellation

• 10-67 — Clear for net message

• 10-68 — Dispatch information

• 10-69 — Message received

• 10-70 — Fire

• 10-71 — Advise nature of fire

• 10-72 — Report progress on fire

• 10-73 — Smoke report

• 10-74 — Negative

• 10-75 — In contact with ...

• 10-76 — En route ...

• 10-77 — ETA

• 10-78 — Need assistance

• 10-79 — Notify coroner

• 10-80 — Chase in progress

• 10-81 — Breathalyzer

• 10-82 — Reserve lodging

• 10-83 — Work school crossing at ...

• 10-84 — If meeting ... advise ETA

• 10-85 — Delayed due to ...

• 10-86 — Officer/operator on duty

• 10-87 — Pickup or distribute checks

• 10-88 — Present telephone number of ...

• 10-89 — Bomb threat

• 10-90 — Bank alarm at ...

• 10-91 — Pickup prisoner or subject

• 10-92 — Improperly parked vehicle

• 10-93 — Blockade

• 10-94 — Drag racing

• 10-95 — Prisoner or subject in custody

• 10-96 — Mental subject

• 10-97 — Check signal

• 10-98 — Prison or jail break

• 10-99 — Wanted or stolen indicated



Note: While ten-codes were intended to be a terse and concise and standardized system, a great deal of diversity between departments and jurisdictions in terms of meanings has been reported. All codes listed above are from the Official Ten-Code List of the Association of Public-Safety Communications Officers.