Sue Gray: what is she investigating and what powers does her inquiry have?

Who is Sue Gray?

Until last month, civil servant Sue Gray, who is heading the inquiry into the “partygate” scandal, was virtually unknown outside Whitehall. She is now one of the best-known figures in government, with senior political figures from the prime minister downwards keen to defer to her judgment over the alleged goings-on in 10 Downing Street.

Gray investigated the senior government minister Damian Green in 2017, an inquiry which triggered his resignation after she found he had broken the ministerial code. A BBC profile of Gray in 2015 described her as “the most powerful person you’ve never heard of”. Her own Twitter account has a retweeted posting in which she is referred to as “deputy GOD”.

Why is she in charge of the partygate inquiry?

Gray, now second permanent secretary at the Department for Levelling Up, Housing and Communities, was drafted in to head the inquiry after Britain’s top civil servant Simon Case stepped aside last month following reports a drinks gathering was held in his office. Her experience in high-profile investigations into personal conduct made her the ideal candidate to conduct the Downing Street inquiry.

What exactly is she investigating?

Michael Ellis, the paymaster general, told the House of Commons on 9 December an inquiry would look at gatherings in Downing Street on 27 November 2020 and 18 December 2020. These were a leaving do for a senior aide, Cleo Watson, where Boris Johnson is said to have given a speech, and a Christmas party, which Johnson did not attend. Ellis told MPs the prime minister had been assured “there was no party and that no Covid rules were broken”.

The inquiry has now been widened to cover other events, most notably the garden party at Downing Street on 20 May 2020, where those attending were sent an invitation by the principal private secretary to the prime minister, Martin Reynolds, suggesting they “make the most of this lovely weather” and advising them to “bring your own booze!”

The country was in lockdown at the time and the terms of reference state the inquiry will establish “a general understanding of the gatherings, including attendance, the setting and the purpose, with reference to adherence to the guidance in place at the time”. It is also looking at two parties held by No 10 staff on the eve of the Duke of Edinburgh’s funeral in April 2021.

The inquiry is also charged with looking at other events in Whitehall during lockdown, including a drinks party at the Department for Education on 10 December 2020.

What powers does the inquiry have?

The inquiry is an internal one and Gray is supported by lawyers from the government legal department. All ministers, special advisers and civil servants have been told to cooperate.

Gray has been given access to all relevant records, which are likely to include internal emails, calendar invites and Downing Street exit and entry logs, and has been interviewing staff. It was reported on Friday that Gray’s team have asked some Downing Street officials to hand over their mobile phones.

Any final decisions on disciplinary action against civil servants would ultimately be a matter for Simon Case, the cabinet secretary. The prime minister would rule on any action against political staff.

Will it rule on whether Johnson and his staff broke the rules?

Under the terms of reference of the inquiry, any potential evidence of a criminal offence in Downing Street will be passed to the police. Gray’s remit is to examine the guidance at the time of the parties.

Johnson and his staff will be anxious about whether she reaches an unequivocal conclusion on whether the parties broke the rules. MPs say it is hard to see how she could conclude that none of the parties breached the guidelines to avoid unnecessary social mixing at the time.

The inquiry is likely to closely examine the culture and management of Downing Street and one source has said she will “give it both barrels to whoever deserves it”.

Those who know her say she will be anxious to avoid junior staff taking the blame for wider failings at No 10.

Will the proceedings of the inquiry be published in full?

The investigation will almost certainly not be published in its entirety and specific action against junior employees will be confidential. Labour and the Liberal Democrats are calling for the publication of the full report and accompanying emails and witness accounts.

Could there be a smoking gun?

Related: Sue Gray: head of No 10 party inquiry is an uncompromising operator

Johnson’s defence in the Commons for attending the garden party in May 2020 was that he “implicitly” believed it was a work event. In an incendiary intervention last week, Johnson’s former chief adviser Dominic Cummings claimed the PM was warned about the drinks party. No 10 says this is untrue.

If Gray uncovers an email or conclusive evidence that Johnson was warned about the event and knew it was a party, it would almost certainly force his resignation since he would have misled parliament and breached the ministerial code.

How will Johnson respond?

Johnson is likely to make a statement to the Commons once the report is published and answer MPs’ questions. He could decide to refer himself to Lord Geidt, the independent adviser on ministerial interests. In the face of a damning report, he will face immediate calls to stand down. If he survives the partygate scandal, Johnson is likely to make sweeping changes to his team.