Sue Gray has been looking into boozing in Downing Street - but she used to be the one pulling the pints.
The civil servant has sent her report into Partygate, the scandal which has plagued Prime Minister Boris Johnson and his government since revelations came to light in December 2020, to No 10 today.
Publishing of her findings was delayed due to an investigation by the Met Police in which the PM himself received a fine and No 10 was forced to deny the PM asked Gray to drop publishing the report.
The Prime Minister accepted he had broken the rules and apologised but refused to resign, while junior Downing Street members reportedly said they felt as though they were "hung out to dry".
But what about the person behind the report, who was described as "the most powerful civil servant you've never heard of".
Gray is now the Second Permanent Secretary in the Department for Levelling Up, Housing and Communities, but she used to lead a rather different life.
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Despite her reputation, with one minister stating "nothing moves in Whitehall unless Sue says so", Gray is the most unconventional of civil servants.
The daughter of Irish immigrants who moved to Tottenham in the early 50s, her dad was a furniture salesman and her mum a barmaid.
After her father's sudden death in 1975, Gray abandoned her plan of going to university and joined the Civil Service straight from school.
Gray, who is now 64, took what was described as a "strikingly unorthodox" career break in the 80s to run a pub in Northern Ireland.
She was landlady at the Cove Bar outside Newry, County Down, a border town that was a hotbed of IRA and security force activity.
"I loved it, loved it at the time, I'd never do it again," she said in May 2021. "I think actually it's a very sociable occupation, very hard work. But I loved meeting people.
"I think it was in a relatively country area, so, a mix of farmers, business people, a great mix of characters, and I got to know them really well and I threw myself into that."
Gray ran the pub with her husband, Bill Conlon, a country and western singer originally from Portaferry in County Down.
Bill has a band called Emerald and he has backed Suzy Bogguss and Randy Vanwarmer in UK appearances.
The family returned to London in 1987 and Gray joined the Cabinet Office in the late 1990s after previous postings to health, transport, and work and pensions
Gray has worked under both Labour and Tory governments andhas a formidable reputation as a highly secretive enforcer.
In 2015, BBC Newsnight’s policy editor Chris Cook described Mrs Gray as "the most powerful civil servant you’ve never heard of" and "also perhaps the most secretive you could ever hope to meet".
She is known for pulling no punches when investigating whether rules have been broken by ministers, officials and special advisers.
During her time in the Cabinet Office, she was in charge of leading investigations into the actions of ministers, with one resulting in the sacking of Theresa May's former deputy, Damian Green, from his Cabinet position.
Image:PRU/AFP via Getty Images)
Gray switched to the Northern Ireland Civil Service as Permanent Secretary of the Department of Finance in the Northern Ireland Executive.
Many believged it was a precursor to her becoming appointed head of the Civil Service, but she failed to land the job after the retirement of David Sterling.
She told BBC NI's The View programme her failure to land the job left her "disappointed " and that she had wanted to bring about change.
"I really wanted the job, but had to get over it," she said. "Why didn't I get the job? I'm not sure I'll ever quite know but I suspect, you know, I suspect people may have thought that I perhaps was too much of a challenger, or a disrupter.
"I am both. Perhaps I would bring about... too much change. And yes, I wanted to have change."
Asked if she had tried to find out why she hadn't got the job, she replied: "I'm not going to go into that but I know that I would have enjoyed it.
"But look, I'm going back now to a job where I really can maintain close links here."
In May last year, Gray came back to Whitehall to become the Second Permanent Secretary in the Cabinet Office and initiialy reported to Michael Gove and then Steve Barclay.
According to The Guardian, the former Tory MP and Cabinet Office minister Oliver Letwin reportedly said of Gray: "It took me precisely two years before I realised who it is that runs Britain.
"Our great United Kingdom is actually entirely run by a lady called Sue Gray, the head of ethics or something in the Cabinet Office."
Gray was thrust into the spotlight last year when she was chosen to lead the Partygate investigation into parties in Downing Street.
Her boss, Cabinet Secretary Simon Case, recused himself following allegations that his own office held a Christmas event in December 2020.
She has now sent No 10 her long-awaited report after the Met completed its probe, issuing more than 100 fines.
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