The Metropolitan Police reopen an investigation into breaches of Covid regulations at a Christmas rally at Conservative Party headquarters.
The Sunday Mirror published a video of the event, where assistants were invited to “play and mingle”.
Police say they will not investigate alleged gatherings at the prime minister’s country home, Checkers, when Boris Johnson was prime minister.
But they are now investigating an event in Parliament on December 8, 2020.
According to the Guido Fox websiteConservative MP Sir Bernard Jenkin participated in the event.
Sir Bernard is a member of the House of Commons Privileges Committee, which last month published a report highly critical of Mr Johnson.
He told the BBC it was not appropriate to comment on the ongoing investigation.
Conservative MP Virginia Crosby issued an apology for attending the event while Covid restrictions were in place.
Ynys Mon MP confirmed the event took place but said she had not sent out any invitations.
Met police investigated a December 2020 gala at Tory HQ last year, after a photograph emerged showing former London mayoral candidate Sean Bailey and Tory aides holding glasses next to a buffet, when indoor social contact was banned in the area.
In November, the Met said they had taken no further action against Mr. Bailey or the others in the photo.
They said they are now reopening their investigation, as the video released by the Mirror had not previously been provided to officers.
An invitation to the gathering, seen by the BBC, invited people to a “jingle and mingle” party.
Bailey – who was given a seat in the House of Lords on Johnson’s resignation honors list – has previously said he apologized “unreservedly” for the event, which he said had “turned into a thing” after he left.
He claimed he was “very upset about the video” because he had “never seen it”.
The Liberal Democrats said that Prime Minister Rishi Sunak should prevent Bailey “from taking his seat as peer while this investigation takes place”.
Meanwhile, Met Police and Thames Valley Police said they would not launch an investigation into a possible breach of the rules between June 2020 and May 2021 at Downing Street and Checkers.
In May, the forces said they were assessing information handed to them by Cabinet Office officials after reviewing Johnson’s official diaries as part of preparations for the Covid investigation.
Thames Valley Police were looking into visits from Johnson’s family and friends to Checkers – the country home of the prime minister in Buckinghamshire – during the pandemic.
The Met has been looking into other possible breaches of the rules in Downing Street.
In a joint statement released on Tuesday, the forces said that after “further clarification” on the diary entries, they had determined that the events “do not meet the retrospective criteria for opening an investigation.”
When news of his referral broke, Johnson denied there had been any Covid breaches at the events, saying the Cabinet Office’s actions bore “all the hallmarks” of a “politically motivated stitch-up”.
The Cabinet Office said at the time that the material it had sent to the police came from a “normal” document review process.
Former Prime Minister Johnson resigned as an MP last month after a House of Commons committee accused him of misleading Parliament about separate events in Downing Street during the pandemic.
The BBC has contacted him for further comment.
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