Boris Johnson may get more taxpayers’ money for Partygate defence

Boris Johnson could get more taxpayers’ money to cover extra legal support as the inquiry into his Partygate denials drags on, it has emerged.

The cost of helping the former prime minister defend himself over claims he misled parliament about law-breaking parties during Covid “could potentially exceed” the current £222,000 budget, a senior civil servant admitted.

Alex Chisholm, the permanent secretary at the Cabinet Office, suggested that while he hoped the figure would be a “maximum”, the government could step in to foot another increase to the bill.

Slower than anticipated progress by the privileges committee means the contract with law firm Peters and Peters has already been extended once, until 28 February, with the £129,000 initially set aside rising to £222,000.

Chisholm said it was normal practice for the government to fund legal support for former ministers “after they have left office when the matters relate to their time and conduct as a minister”.

However Alex Thomas, the programme director at the Institute for Government, said that given the process looked “likely to run for many more months, this is an open-ended commitment by the government to defend the former prime minister’s personal conduct”.

He added it was “hard to justify the taxpayer funding Boris Johnson’s personal legal advice”.

It came as the former prime minister’s latest entry in the register of members’ interests says that he “received £510,000 as an advance on an upcoming book yet to be published” – even though he has so far done just 10 hours work on it.

Angela Rayner, Labour’s deputy leader, said those struggling with the cost of living would be “justly outraged at the prospect of having to stump up yet again to subsidise Johnson’s Partygate defence fund”.

She said hundreds of thousands in public money had “already been wasted”, and that Rishi Sunak had been “once again too weak to put a stop to it”.

Related: Boris Johnson reportedly joked about being at ‘UK’s most unsocially distanced party’ during lockdown

It emerged this week that several former Downing Street staff have only just been contacted by the privileges committee. Some gave evidence to the Sue Gray inquiry conducted a year ago, and have been encouraged to confirm that their testimony then was true as part of a programme of “informed outreach”.

“That evidence is incredibly valuable, because it’s contemporaneous. It would be much harder asking people what happened 18 months down the line,” one insider said.

The former staff members have also been asked for any knowledge of briefings given to Johnson about the 16 gatherings during lockdown, and whether they raised concerns with senior staff at the time.

The questions are designed to discover whether Johnson misled MPs when he repeatedly said in the House of Commons that no Covid rules were broken in No 10, before 100 fines were issued by Scotland Yard for the string of illegal gatherings.

Johnson continues to protest his innocence. His allies say he is the subject of a “witch hunt” and a written legal opinion from the barrister and crossbench peer David Pannick, instructed by Peters and Peters, accused the committee of adopting an unfair practice.

Part of the reason for the inquiry’s slow progress was a refusal by the Johnson and Liz Truss administrations to hand over much of the evidence requested in July, which included information such as door logs, WhatsApp messages and photos. What was provided was heavily redacted and effectively “useless”, the Guardian has been told.

A large cache of documents was finally given to MPs on the seven-member committee, chaired by Labour’s Harriet Harman but with a Conservative majority. When it was handed over in November, a source admitted “it was like starting from scratch”.

Though the next stage of the inquiry, involving public hearings, was mooted to start in early February, that appears unlikely. Witnesses, who will include Johnson, are expected to be given two weeks’ notice before they are called before the committee.

Sources have indicated that MPs running the inquiry will wait until at least the 7 February deadline for new written evidence requests, before sifting through them and sending any follow-up questions based on “incomplete or ambiguous” answers.

The Guardian has been told the aim remains for the hearings to be concluded and a final report written by the end of March – though the committee has not published an official deadline and disputes this. Any potential sanction, which could include a suspension and byelection if it is for 10 days or more, has to be voted on by the Commons.