Here is what I think will be in Sue Gray’s report

We can predict what the report will say, but Conservative MPs are more interested in who will win the next election

A cartoon in Private Eye has a man cheerily greeting a neighbour: “Nice day!” The other replies: “We should wait for Sue Gray’s report before making a judgement.” The whole country is waiting for Gray’s findings as if they will decide the prime minister’s fate and therefore the direction of the nation.

But we already know what Gray, a senior civil servant with long experience in charge of ethics at the Cabinet Office, is likely to say. There may have been other parties in Downing Street, and there may be new details that have been reported to her by the people she has interviewed, but the main facts are known. If we look at the terms of reference of Gray’s inquiry, it is possible to guess what her report will be like.

The terms of reference say that “the primary purpose” of her investigations is “to establish swiftly a general understanding of the nature of the gatherings, including attendance, the setting and the purpose, with reference to adherence to the guidance in place at the time”.

An important word there is “guidance” rather than “regulations”, which means that she will not be making any direct findings about whether there might be a case against anyone for breaking the law. She will be looking at whether ministers and officials followed the government’s own advice.

At least two parties from which Boris Johnson was absent do seem to have been in breach of the guidance. There was the Christmas party in No 10 on 18 December 2020 – about which Allegra Stratton, the prime minister’s former spokesperson, was asked in a rehearsal for a news conference. The guidance at the time said: “You must not have a work Christmas lunch or party, where that is a primarily social activity.” I doubt if Gray will be persuaded that handing out prizes is enough to activate the “not primarily social” exclusion.

Then there was the party in the basement of No 10 on 16 April last year – the one which ended with Wilf’s swing in the garden being broken. Again, that would seem to be in breach of the guidelines for step two of the “road map” out of lockdown.

In both cases, some officials seem likely to be told off, although Gray’s terms of reference say that “any specific HR action against individuals will remain confidential”.

The implications for Johnson, however, are limited. Gray may have some words about how unwise it was for the prime minister to allow his staff to form the impression that he thought shipping suitcases of booze into the party house was absolutely marvellous. But he wasn’t there. Alibi in Latin means “elsewhere”.

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Two other alleged gatherings may be more dangerous for Johnson. We do not know the full story, and here Gray may add to the sum of public knowledge. Dominic Cummings, Johnson’s former chief adviser, claims that Boris and Carrie held a party in the Downing Street flat to celebrate his departure on 13 November 2020 – the second national lockdown having come into effect eight days earlier. And Johnson is reported to have made a speech at a leaving party for Cleo Watson, a special adviser, two weeks later. However, I suspect nothing is going to come of either of these.

The main event, therefore, is likely to be the “bring your own booze” gathering in the Downing Street garden on 20 May 2020, during the first lockdown. About which we already know most of what we need to know. The government’s guidance at the time is unhelpful, because it wasn’t written to cover the unusual situation of an office with a private garden.

In law, the prime minister has an arguable case that it was “reasonably necessary for work” that staff should gather to be thanked for their efforts. That doesn’t cover the “bring your own booze” email invitation and a loud party continuing for some hours after people had been thanked, but Johnson said he didn’t see the email and was only at the “work event” for 25 minutes. He also denied that anyone had suggested to him that there was any doubt that the event was within the rules. This contradicts Cummings’s claim that he and another official warned him, but I imagine that Gray will avoid adjudicating on a “who said what” dispute with a former adviser who has made it clear that he is out to remove the prime minister from office.

In any case, simply laying out the facts will confirm everyone in the view they hold now, which in most cases is that the party in the Downing Street garden was clearly contrary to the spirit of the guidelines. Indeed, Johnson admitted it himself, saying that, “in hindsight” – and he has the gall to call Keir Starmer Captain Hindsight – he should have told everyone to go inside.

We know, therefore, that Gray will find that the gathering should not have happened, and that Johnson was responsible for it, even if Martin Reynolds, his principal private secretary, sent the email invitation and is likely to be criticised as well.

When her report is published, therefore, there is likely to be a propaganda exercise from No 10 declaring that it says nothing new, or nothing significantly new, that the prime minister has apologised to parliament and the country, and that it is time to unite and get on with delivering the people’s priorities.

But the importance of the publication of the report is that it is for Conservative MPs a moment of decision. They will have given the prime minister the benefit of due process, which will have concluded what he has already reluctantly admitted. He made an error of judgement. For a large number of voters it was a serious enough mistake to require his resignation.

But Conservative MPs are not waiting for Gray’s findings; they are waiting for the publication of her report as the moment to trigger – or to refrain from triggering – the removal of Johnson and his likely replacement by Rishi Sunak. They will make that decision not on what they think of what happened in the garden of Downing Street 20 months ago, but on who they think will best put them in an election-winning position in 20 months’ time.