(AFP) - Britain's former prime minister Boris Johnson re-enters the bear pit of parliamentary inquisition on Wednesday for a grilling about "Partygate" that could decide his political future.

In July, the end of Johnson's three years in 10 Downing Street played out in another parliamentary committee hearing, while outside the room his government was collapsing in a wave of ministerial resignations.

Voters' anger at the scandal about serial partying at Downing Street, in breach of Covid lockdown laws, was one backdrop to the resignations.

But Johnson's supporters insist he was betrayed by Conservative colleagues, and are campaigning for his return ahead of a general election likely next year.

Opinion polls suggest that Johnson remains toxic for a large swathe of the electorate, and Wednesday's hearing by the cross-party privileges committee will reopen old wounds just as his eventual successor, Rishi Sunak, tries to salve the body politic.

If the committee decides that Johnson lied to parliament about the parties, it could recommend his suspension from the House of Commons.

If the full House agrees to a suspension of more than 10 sitting days, that could trigger a special election for his northwest London seat, if enough voters demand one.

Ahead of the televised hearing, Johnson was defiant as he released a 52-page dossier detailing his belief that he was truthful when he told the Commons on several occasions that all Covid rules were respected.

In hindsight, he recognised that he did "mislead" the House, but only inadvertently and based on assurances given by top aides that the rules were being followed.

"I did not intentionally or recklessly mislead the House" on any date, he wrote. "I would never have dreamed of doing so."

Johnson was fined by police for one Downing Street gathering, along with Sunak, his finance minister at the time.

The former Conservative leader apologised and corrected the parliamentary record last May after previously insisting to MPs that the gatherings were above board.

- 'Lack of shame' -

Johnson said his statement in May came at the earliest opportunity -- after London police and senior civil servant Sue Gray had concluded their own investigations.

"But when the statements were made, they were made in good faith and on the basis of what I honestly knew and believed at the time," he said, blaming senior advisors for giving him false assurance.

Johnson nearly died himself of Covid, but relatives of patients who did die said his claims were a brazen attempt to evade responsibility.

"Johnson's defence continues to highlight his lack of shame and humility," said Kathryn de Prudhoe, a psychotherapist whose father died early in the pandemic.

"The victims in all of this are families like mine who lost loved ones in the most traumatic circumstances, people who lost their jobs, livelihoods and homes or their mental health because they followed the rules that he made, but couldn't stick to," she said.

The successive waves of Covid from 2020 claimed the lives of more than 220,000 people in Britain, the second-worst toll in Europe behind Russia's.

A public inquiry is looking into the government's overall response, and is likely to take years.

Despite having a Conservative majority, the privileges committee has been accused by Johnson loyalists of pursuing a "witch hunt", and in his dossier, Johnson accused its members of being partisan and straying beyond their remit.

The committee defended the "fairness of its processes", adding: "Mr Johnson's written submission contains no new documentary evidence."

This month, the MPs found in an interim report that Johnson should have known the rules were being flouted.

They released previously unseen photographs and also published WhatsApp messages showing senior aides struggling to come up with a public justification for the parties.

Meanwhile on Wednesday, The Times reported that the evidence showed that one of Johnson's most senior advisers warned him against saying that the rules had been followed "at all times".

© Agence France-Presse