Line of Duty Season 5 police acronyms: What is an OCG? What about an AFO?
- Posted by
- Stylist Team
- Published

A complete guide to all the abbreviations you may not know that have cropped up in Line of Duty (warning: there will be season 5 spoilers)
After a two year wait almost as tense as the BBC police drama itself, Line of Duty season 5 smashed its way back onto to our screens in March 2019. The first episode of the new series pulled in a massive 8 million viewers, dominating 38% of the total TV audience share in the UK for the Sunday night.
The eagerly awaited series five opener saw a 2.5 million increase in viewers than the season four opening episode, making it the most watched instalment of Line of Duty ever. This no doubt follows on from the gap left in the wake of screenwriter and creator Jed Mercurio’s other phenomenally successful political drama Bodyguard, which aired in January this year to critical acclaim and ended with the most-watched episode of any single drama since records began.
A seemingly tough act for Jed Mercurio to follow - but so far every episode of Line of Duty season five has had us on the edge of our seat and left us with more burning questions than the last. Who the hell is H? What is AC-12 leader Ted Hasting hiding? Is there more than one UCO? But most importantly, what even is an a UCO, or an AFO for that matter?
One of many things we love about Jed Mercurio is that he always assumes intelligence in the TV audience watching his gripping dramas and never dumbs down happenings to help us follow what’s going on - and police terminology is no exception.
But, while we appreciate this, if you’re anything like us you might have got a little confused by some of the police acronyms and legal terminology used in Line of Duty. So no need to frantically Google the police abbreviations used in the show, here’s a handy glossary to help you out, so you can concentrate on the action in the latest episode…
You’re welcome.
AC-12: anti-corruption unit 12
Use: “PC Cafferty, DI Fleming, AC-12.”
ACC: assistant chief constable
Use: “Sir, he was the ACC. I honestly believed it was lawful.”
AFO: authorised firearms officer
Use: “Three AFOs pronounced dead at the scene.”
COM: covert operations manager
Use: “If you have any doubts, you just watch how fast I’m going to shut down this operation, and serve you, your COM and your UCO with Reg 15s.”
DI: Detective Inspector
Use: “DI Fleming, AC-12.”
IR: intelligence report
Use: “Control, Charlie Zulu Five Five, request IR.”
MOPI: management of police information
Use: “There was a code associated with the MOPI notice.”
OCG: organised crime group
Use: “The fire arms and balaclavas all fit with the established OCG activity.”
Reg 15: notice of misconduct/gross misconduct
Use: “If you have any doubts, you just watch how fast I’m going to shut down this operation, and serve you, your COM and your UCO with Reg 15s.”
RTC: road traffic collision
Use: “RTC up ahead.”
Sit rep: situation report
Use: “Stand by for sit rep” / “request sit rep.”
UCO: undercover operative
Use: “Is there a UCO embedded in the OCG that carried out the heroin hijack?”
VO: visiting order
Use: “It’s ok, I used a false name on the VO.”
Line Of Duty continues next Sunday 9pm BBC One and is on iPlayer now
Images: BBC One