SUE Gray, the senior civil servant tasked with leading an inquiry into alleged Number 10 rule-breaking during coronavirus lockdowns, is also involved in upholding the Union.

Since May 2020, the Cabinet Office official has had the role of second permanent secretary with responsibility for the Union and the Constitution. The position also sees her with responsibilities in Michael Gove’s Department for Levelling Up, Housing and Communities.

According to the UK Government, Gray is responsible for both the Union Directorate – a team of around two dozen Whitehall workers based in the Cabinet Office particularly focused on preventing Scottish independence – and the UK Governance Group, which focuses on “constitutional and devolution issues”.

Now, Gray has been handed responsibility for finding the facts amid a litany of claims that ministers and Government staff partied in contravention to Covid-19 restrictions.

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Her remit includes looking into the allegation that Downing Street staff, including Prime Minister Boris Johnson and his wife Carrie, attended a “bring your own booze” party on May 20 2020, at a time when more than two people were banned from socialising outdoors together.

While Gray might be an elusive character to the public, some politicians have gone so far as to suggest the former publican is the “real leader” of the UK.

In her former role as director-general of propriety and ethics in the Cabinet Office from 2012 to 2018, she is said to have overseen Cabinet reshuffles, served as a guiding hand in compiling honours lists, and even signed off political memoirs before their publication.

The diplomacy skills required for such a sensitive role might well have been honed in a location far removed from Whitehall, when Gray and her country and western singer husband Bill Conlon bought and ran a pub in Newry, Northern Ireland, at the height of the Troubles in the late 1980s.

Last month, Gray, said to be in her mid-60s, found herself thrust into the limelight after being chosen to step in to lead the investigation into possible wrongdoing in Downing Street after Cabinet Secretary Simon Case – her boss – recused himself following allegations that his own office held a Christmas event in December 2020.

The probe will see her investigate Johnson – leaving her in a “very difficult” position, according to a former senior mandarin, but one she is “best” placed for despite it being a “step beyond anything she will have done in the past”.

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Sir David Normington (below), a former Whitehall permanent secretary, told BBC Radio 4’s Today programme: “She will be very aware that she has the reputation and possibly the careers of senior civil servants and possibly of the Prime Minister in her hands, and that is a very difficult position to be in, however fair and fearless and rigorous you are.”

But he added: “If we are going to have a civil servant doing it, Sue Gray is the best person to do it.”

The National:

Gray’s reviews of senior Cabinet ministerial behaviour in the past have led to high-profile sackings and resignations.

Former prime minister Theresa May tasked her with investigating her close ally, Damian Green, over allegations that he had lied about the presence of pornographic images on his Commons computer, and she also spearheaded the so-called “plebgate” inquiry into claims that then-chief whip Andrew Mitchell had insulted police officers on Downing Street.

David Laws, a former minister in the coalition government, said David Cameron’s former policy chief, Oliver Letwin, once told him that Gray was the brains behind the UK Government operation.

Writing in his memoir about the 2010-15 power-sharing administration, Law quotes Letwin as saying: “Our great United Kingdom is actually entirely run by a lady called Sue Gray, the head of ethics or something in the Cabinet Office.

“Unless she agrees, things just don’t happen. Cabinet reshuffles, departmental reorganisations, the whole lot – it’s all down to Sue Gray.

“Nothing moves in Whitehall unless Sue says so. She gets to censor our memoirs too!”

Former chancellor George Osborne suggested Gray has not been shy about reprimanding prime ministers in the past.

Following Gray’s appointment to head up the No 10 inquiry, he tweeted: “On our night in Downing Street in 2010 – 30 minutes after the Labour team had left – everyone was fawning at David Cameron.

“Then someone spoke out: ‘I’m sorry PM, but you can’t do that’. ‘Who’s that?’ I asked. Sue Gray.”

READ MORE: Downing Street parties: No 10 staff told to 'clean up' phones

Some critics have suggested Gray has been influential in blocking freedom of information requests, with former BBC Newsnight journalist Chris Cook reporting in 2015 that she was “notorious for her determination not to leave a document trail” and had assisted departments to “fight disclosures”.

According to her Government biography, Gray started working for the Cabinet Office in the late 1990s following her stint behind the bar in Northern Ireland during a “career break”.

After her time as head of ethics in the Cabinet Office, she served as the permanent secretary of the Department of Finance in Northern Ireland from 2018 to 2021, before taking up her current post.