“Waiting for the independent review” is the holding statement with which Downing Street is avoiding answering any question about the specifics of the Prime Minister’s involvement in his staff’s party on 20 May 2020. The non-answer was reeled out repeatedly as Boris Johnson endeavoured to straight bat every seamer, bouncer, yorker and daisy-cutter bowled at him at PMQs today. It is also the response to almost every question that lobby journalists are putting to the unfortunate spokespeople sent out to the crease on Johnson’s behalf.

It is a response which effectively says that nothing will be revealed by those involved until everything is revealed by an independent civil servant (commissioned by Johnson), with uncovering what those involved did or knew.

From a damage limitation perspective, it has one advantage. Endeavouring to avoid a daily drip of more revelations, it seeks to starve the story of oxygen until the eventual, unavoidable, moment of detonation when Sue Gray’s report is published. Before that moment, lobby journalists can go on as many fishing trips for information as they like — was so-and-so at the party? Whose idea was the party? If it was a work outing why was Carrie Johnson there if she was there? — and get the same “wait for the independent review” response.

But to be successful the strategy assumes that nobody else with credible access to the facts has an interest in speaking out of turn. Since those involved were Downing Street staff there is perhaps no great incentive to speak freely to journalists about events on the sunny day for fear of incriminating friends and colleagues. Then again, involvement goes beyond current Downing Street staffers to include such disgruntled alumni as Dominic Cummings, who does not feel loyalty’s call upon omerta.

How long can this shtoom last? The Prime Minister’s spokespersons are providing no guidance on when Sue Gray’s report will see the light of day. At PMQs today, Johnson expressed the hope that it would be “as soon as possible” — an elastic timescale. In March 2020, Johnson commissioned Sir Alex Allen, as the watchdog for ministerial behaviour, to investigate allegations by Priti Patel’s former permanent secretary that she bullied him in breach of the ministerial code. The report took eight months to be published. It resulted not in the resignation of the Home Secretary, but of Sir Alex.

We are left to infer that he saw the party going on from his window

Nobody is billing Sue Gray as a patsy. Certainly not the former First Secretary of State (and de facto deputy prime minister), Damien Green, who was forced to resign as a result of the report into his alleged inappropriate behaviour that Sue Gray, as a Cabinet Office civil servant, prepared for Theresa May. That report took seven weeks to conclude.

But, regardless of the time it takes, what should we expect from Gray’s review? Beyond ascertaining the facts, much remains unclear about the extent of her remit. Or indeed actions. It seems slightly strange, given the way her immediate predecessor, and superior, Simon Case, the Cabinet Secretary, came a cropper, that she hasn’t felt obliged to state for the record her own immaculately partyless 2020.

Will she merely establish whose idea the party was, what it entailed, who knew it was happening, who was at it, and the extent and nature of Johnson’s involvement? Or will she produce recommendations?

If the latter, is the Prime Minister bound to accept them? Unsurprisingly, Downing Street won’t say whether Johnson will accept notional recommendations that do not yet exist, only going so far as to state that “Sue Gray has the Prime Minister’s backing” and that he will accept the facts as she finds them. But Downing Street is offering no guidance on whether Gray will provide recommendations, merely stating that “it is up to her”.

Gray’s report into Green’s behaviour did not include a set of conclusions, but was deemed sufficient to force his resignation. But Johnson is not Green and there is no inevitability that the approach Gray took to investigating supposed sleezy conduct is how she will investigate allegations of Covid rules-breaking at Downing Street.

It seems likely that it will be weeks or months before Gray’s report is published

If she produces not only recommendations but, from these, goes on to propose tough sanctions — who is empowered to approve and enforce them? Despite repeated efforts to elucidate where the buck stops, Downing Street will not be drawn on this.

For now, the Prime Minister’s spokespeople are going into no detail beyond maintaining that Johnson was not sent and did not see an email from his principal private secretary, Martin Reynolds, inviting him to the drinks party. From this, we are left to infer that he saw the party going on from his window and popped out to join it in order to thank the attendees for their hard work when, as he conceded in Parliament, he should have only joined it in order to shut it down. It will be up to Sue Gray to support or undermine this interpretation of events in which the Prime Minister seeks to portray himself as the collateral damage of the misjudgement of his team — an error in which he was a subordinate rather than central figure.

Whatever the findings, it seems likely that it will be weeks and likely months before Gray’s report is published. A lot can happen in months (and in Johnson’s premiership usually does). No wonder Downing Street is playing for time.