Police Code 901 Meaning

901 (also written code 901, or 901A for an injury) has no single meaning. It depends on the agency’s list. Alameda and Albany use it for an accident, Phoenix for an injured or sick person, Mesa for a shooting, Coolidge for a dead body, and Downey for an abandoned or illegally parked vehicle.

These meanings come from each agency’s own code list or dispatch manual: the Alameda, Albany and Downey police departments in California, and the Phoenix, Mesa and Coolidge police departments in Arizona. There is no standard, so check which agency’s list applies.

What 901 means

Six of the 46 official lists we checked print 901, and they do not agree. In Alameda, 901 is “Accident”, and its call-type section words it “Accident, non-injury”. Albany lists it as “Vehicle Collision, Non-injury”. Downey, which uses 901 as a CAD call type, words it “Vehicle Abandoned, Ill Parked”. In Arizona, Coolidge lists 901 as “Dead body”, Phoenix as “Injured or sick person” and Mesa as “Shooting”.

901 meaning by agency

Each published meaning we have is listed below, with its source.

Two of the six, Alameda and Albany, are about a vehicle accident or collision without injury. The other four are a parking problem (Downey), a dead body (Coolidge), an injured or sick person (Phoenix) and a shooting (Mesa). The other 40 lists, including the California Highway Patrol’s card, do not print 901.

The 900-series: same numbers, different jobs

Albany’s communications manual calls its list the “Nine Code” and says Oakland, Alameda and San Leandro are “some of the few departments in the area” that use it. In that list 908 is “Out of Service”, 909 is “In Service, Available” and 905 is “Abandoned Vehicle”.

Phoenix’s 900 block is mostly about people. It lists 900 “Check welfare”, 901 “Injured or sick person”, 906 “Officer needs help”, 907 “Back-up” and 918 “Mentally ill subject”. Mesa’s list is similar but moves the meanings: 900 “Welfare Check”, 901 “Shooting”, 902 “Stabbing”, 903 “Dead Body” and 918S “Suicide Threats/Attempt”.

The Phoenix, Mesa and Coolidge lists all put accidents in the 960s. Phoenix has 961 “Accident - no injuries”, 962 “Accident with injuries” and 963 “Accident - fatality”. Mesa has 961 “Accident”, 962 “Accident with Injuries” and 963 “Fatal Accident”, and Coolidge has 961 “Accident no injuries”, 962 “Accident with injuries” and 963 “Accident fatal”.

Downey’s 9xx numbers are CAD call types, such as 917 “Disturbance-415 Subjects” and 927 “Possible Burglary-459”. In the radio list of the same Downey manual, 961 means “No wants/record your subject”, while in Phoenix, Mesa and Coolidge 961 is an accident. A 900-series number tells you little without the agency’s list. See our guide on why police code meanings vary.

901A and the other letters

A letter after the number narrows the meaning. Alameda lists 901A as “Injury Accident”, and Albany lists it as “Vehicle Collision, Injuries”.

Phoenix uses letters more widely: 901C “Cutting/stabbing”, 901G “Shooting”, 901H “Dead body”, 901M “Medical practice violation”, 901O “Overdose victim”, 901U “Suicide” and 901X “Attempt suicide”. So 901H in Phoenix is the meaning that Coolidge gives to plain 901, and Phoenix’s 901G is the meaning Mesa gives to plain 901. Mesa lists dead body as 903. For related codes see 11-44, a fatality or coroner’s case in California lists.

How 901 is used on the radio

Alameda’s dispatcher program is the one source that describes procedure, and it spells the code the way it is spoken: “nine o one” and “nine o one a”. For a 901, it says the department takes accident reports when the accident has just occurred, both parties are still on the scene and it happened on public property. It takes no cold reports and no private-property reports, and callers on private property are told to exchange information. The dispatcher also notifies the CHP of all accidents involving a school bus with students on board.

For a 901A the department takes the report on private or public property, and takes cold injury reports. The dispatcher notifies ACRECC to send AFD, who dispatch an ambulance. The other lists define the code but do not describe a procedure.

FAQ

What is a 901 police code?

It depends on the agency. Alameda and Albany use 901 for an accident or vehicle collision with no injury, Phoenix for an injured or sick person, Mesa for a shooting, Coolidge for a dead body, and Downey for an abandoned or illegally parked vehicle.

Does code 901 mean a car accident?

In the Alameda and Albany lists, yes: 901 is a non-injury accident or collision. In the Phoenix, Mesa and Coolidge lists in Arizona it is not, and those lists put accidents in the 960s.

What is 901A?

In Alameda 901A is “Injury Accident”, and in Albany it is “Vehicle Collision, Injuries”. Phoenix does not use it for a collision; its 901 letters include 901C cutting/stabbing and 901H dead body.

Does 901 mean a dead body?

Only in some lists. Coolidge, Arizona lists 901 as “Dead body”. Phoenix uses 901H for “Dead body” and plain 901 for “Injured or sick person”, and Mesa uses 903.

Sources

1. General Orders Chapter 81: Communications (81.1.2 Communication Codes), Coolidge Police Department. Updated 6-24-13. Official Checked October 2026
2. Radio Frequencies & Radio Codes, Mesa Police Department. Official Checked October 2026
3. Phoenix Police Department – Radio Codes – Numerical Order, Phoenix Police Department. Updated 3/17/26. Official Checked October 2026
4. Public Safety Dispatcher Training Program (radio codes, pp. 8-9), Alameda Police Department. Official Checked October 2026
5. Communications Training Manual (radio codes, pp. 20-22), Albany Police Department. Official Checked October 2026
6. Communications manual (radio codes), Downey Police Department. Official Checked October 2026