Officials say Boris Johnson likely misled parliament about the extent of violations of lockdown orders during his tenure as prime minister.
The Parliamentary Privileges Committee, which is investigating the allegations, today issued an update to its inquiry ahead of Mr Johnson’s public oral testimony in the week beginning March 20.
The group, whose investigation is being led by Labor MP Harriet Harman, said: “The evidence strongly suggests a breach of the guidelines would have been obvious to Mr Johnson at the time he was at the assemblies.”
The commission also cited two WhatsApp messages which they say show “proof that those advising Mr Johnson what to say to the press and in the House have themselves struggled to claim that some gatherings are within the rules.”
One of those texts, from then Downing Street communications director Jack Doyle, in response to a possible description of the event as “reasonably necessary for business purposes”, read: “I’m not sure it works.
“It’s making another big hole in the Prime Minister’s account, isn’t it?”
The commission added that there was evidence that Parliament had been misled in various ways and on various occasions.
They said: “The committee will want to hear from Mr Johnson why, rather than amending the protocol at the earliest opportunity, he refused to answer questions that were within his direct knowledge.”
In early February, an investigation into an Abba-themed party took place just hours after Dominic Cummings and Lee Cain, Downing Street’s former chief counsel and Johnson’s then-partner and now-wife, Carrie Symonds, were involved in an investigation.
Mr Johnson has consistently denied knowingly misleading Parliament about Downing Street parties that violated the rules and guidelines of his own government while in office.
Prior to the parliamentary committee inquiry, the allegations against the former prime minister had already been the subject of two other inquiries: one by the Metropolitan Police and the other by senior official Sue Gray.
Earlier this week, it emerged that Mrs Gray had been offered the position of chief of staff by Labor leader Sir Keir Starmer.
Mr Johnson’s allies described the job offer as evidence that the allegations against him were part of a “deliberate and fabricated plot to overthrow the Brexit-supporting Conservative prime minister”.