Boris Johnson could face a recall petition which could trigger a by-election if he is suspended by MPs investigating whether he lied over Partygate, the Commons Speaker Sir Lindsay Hoyle confirmed.
The Privileges Committee examining whether the prime minister mislead parliament has set out the terms of their inquiry, insisting the probe will go ahead despite his resignation.
The Speaker confirmed that the committee’s findings – if they deem Mr Johnson worthy of suspension – would fall within the remit of the Recall of MPs Act, following advice from a leading lawyer.
The committee said Sir Lindsay ruled that the “any suspension of the requisite length (ten sitting days or fourteen calendar days) following on from a report from that committee will attract the provisions of the Recall of MPs Act”.
A recall petition would mean Mr Johnson’s constituents in Uxbridge and South Ruislip could trigger a special election to remove him before the next general election.
For any recall petition to be successful it requires 10 per cent of registered voters in a constituency to sign the petition. The committee suggested one could be set up in the “hypothetical” scenario that Mr Johnson is suspended for 10 days.
If the 10 per cent threshold is reached then the seat becomes vacant and a by-election is then required – but the recalled MP may stand again as a candidate.
The Privileges Committee has also insisted its inquiry will still go ahead, despite Mr Johnson’s resignation as Tory leader and his expected departure from No 10 in early September.
The cross-party committee said “some have suggested” the inquiry is no longer necessary. “Our inquiry, however, is into the question of whether the House was misled, and political developments are of no relevance to that.”
The group of senior MPs added: “The House charged the committee with this task and we are obliged to continue with it.”
The committee confirmed that staff will be able to give anonymous evidence on parties in No 10 and Whitehall suggesting whether or not Mr Johnson lied to parliament during the saga.
The MPs vowed to protect anonymous whistle-blowers who wish to submit evidence as “some witnesses may only be willing to give evidence if their identity is not made public”.
A report published by the committee on Wednesday also said that when considering the allegations against Mr Johnson, the standard of proof will be “on the balance of probabilities”.
The cross-party committee unanimously backed Labour grandee Harriet Harman to chair the investigation that could determine Mr Johnson’s legacy.
The committee said it expects oral evidence sessions to begin in the autumn, meaning the inquiry will hang over Mr Johnson’s head for months, even after he departs No 10 and returns to the backbenches.
Downing Street last month disowned allies’ claims that the parliamentary inquiry into his Partygate statements will be a “kangaroo court” – insisting that Mr Johnson trusts the cross-party committee to deliver a fair verdict.