What do all the Line of Duty acronyms mean?

Struggling to keep up with the police jargon in series five? We've got you covered

WARNING: Embargoed for publication until 00:00:01 on 02/04/2019 - Programme Name: Line of Duty - Series 5 - TX: n/a - Episode: Line of Duty S5 - Episode 2 (No. 2) - Picture Shows: ***EMBARGOED TILL 00:01 2ND APRIL 2019*** Steve (MARTIN COMPSTON), Kate (VICKY MCCLURE), Tatleen (TAJ ATWAL) - (C) World Productions - Photographer: Aiden Monaghan

Do you know your ACC from your AC-12? And what on earth is an OCG? Line of Duty is returning to our screens with a series rerun, kicking off with season one on Monday nights from August 2020.


Whether you’re a newcomer to this gripping series of bent copper-busting action, or you’re about to binge the show’s most recent, fifth season, you’ve been warned – each episode is littered with police jargon.

The jargon and acronyms can be tricky to get your head around – and not just for viewers, but for cast members too.

“You have to really work on Line Of Duty, because the language is very difficult and what you’re describing is usually very technical and detailed, so you can’t busk it,” Adrian Dunbar, who plays Ted Hastings, said ahead of season five’ release. “So it’s just a question of getting your head down.”

Keeping track of all the acronyms they throw in is no picnic, especially since Line of Duty is sort of based on a real story, so we’ve done up a handy guide – check it out below.

The first-ever episode of Line of Duty is set for a TV repeat on Monday 3rd August 2020 on BBC One. Tune in before heading over to our cast aftershow Q&A.

Police rankings:

It’s hard to keep up with police ranks and what they mean – Kate Fleming has gone from DC to DS to DI in the time we’ve known her. The below list is in hierarchical order:

DC – Detective Constable (cops who have passed their detective exams get a “D” instead of “P” before their rank)

DS – Detective Sergeant

DI – Detective Inspector

DCI – Detective Chief Inspector

Det Supt – Detective Superintendent

DCS – Detective Chief Superintendent

ACC – Assistant Chief Constable

DCC – Detective Chief Constable

CC – Chief Constable

Other police roles:

Ever felt a bit flummoxed by police roles? FI Tim Ifield? SIO Roz Huntley? Here’s a few acronyms you probably need deciphering… 

TFC – Tactical Firearms Commander

AFO Authorised Firearms Officer

SFC ­– Strategic Firearms Commander

CSECrime Scene Examiner

FI Forensic Investigator

FLO – Family Liaison Officer

FME – Forensics Medical Examiner

PCSO – Police Community Support Officer

SIO – Senior Investigating Officer

UCO – Undercover Officer

Commands and codewords:

“Fahrenheit” – Line of Duty’s codeword for “shoot to kill”. Different police operations use different codewords.

Status zero – Radio code, officer needs immediate assistance

Status five – Radio code, en route to incident scene

Status six – Radio code, on scene

Ten eight – Radio code, in service

Other acronyms:

“OCG” is a term you hear bandied around a LOT in Line of Duty – here’s an explanation of what it means, plus a load of other handy police terms:

AC-12 – Anti-Corruption Unit 12

ARU – armed response unit

CPS – Crown Prosecution Service

DIR – digital interview recorder

DPS – Directorate of Professional Standards

ED905 – this is just an arbitrary code. In series five it represents a truck load of heroin. 

IRV – incident response vehicle

MoPI – Management of Police Information

OCG – organised crime group

PR – police regulations

Reg 15 – Regulation 15 notice. Advises an officer that a complaint has been made or a matter has come to light about them that warrants an investigation.

RUC – Royal Ulster Constabulary, the police force in Nothern Ireland from 1922 to 2001. AC-12 chief Ted Hastings served in the RUC during his days as a constable.

RTC – road traffic collision

SCG – serious crime group

Sitrep – situation report


Looking for something to watch? Check out our handy TV Guide.