Officers will contact those who they believe attended said gatherings at Number 10 and Whitehall during lockdown.
Boris Johnson is believed to be among the 50 people being prepared to be contacted as part of the investigation, which has been named Operation Hillman.
The news comes shortly after it was announced that officers are reviewing a decision to not investigate an alleged Christmas party in Downing Street after a photo of the Prime Minister at the gathering emerged.
When will the alleged attendees be contacted?
The Met Police have issued a statement which confirms that questionnaires will begin to be sent out to those they believed were involved with parties which are currently under investigation.
The questionnaires will be sent out by the end of the week.
What will the questionnaires involve?
In the same statement, Met Police officers said that those involved will be asked for “an account and explanation of the recipient’s participation” in the event or events.
Those who receive a questionnaire will be reminded that the form has “formal legal status” and they they will be required to submit their answers within seven days.
However, police have confirmed that being contacted to fill in the questionnaire as part of the investigation does not mean that a fixed penalty notice will be issued.
The statement continued: “Nevertheless, if following an investigation, officers believe it is appropriate because the Covid regulations have been breached without a reasonable excuse, a fixed penalty notice will normally be issued.
“We understand the interest in and impact of this case, and are progressing the investigation at pace. We are committed to completing our investigations proportionately, fairly and impartially.”
Which parties are being investigated?
Currently, there are 12 alleged parties currently under police investigation.
This was revealed after senior civil servant Sue Gray published her limited report on 31 January on the alleged lockdown-breaking gatherings, in which she detailed that all but four of the 16 cases she looked at were currently being investigated by police.
As a result of the ongoing investigation, Ms Gray was limited in what she could say in her report.
However, we do know that the events under investigation includes a gathering in the Downing Street garden on 20 May 2020, a birthday celebration for Mr Johnson in the Cabinet Room which took place on 19 June 2020 and a leaving party for a special advisor which took place on 13 November 2020.
Mr Johnson is confirmed to have attended all three of these gatherings.
An alleged gathering in the Number 10 flat on 13 November 2020 is also being investigated, although it has not been confirmed if the Prime Minister was in attendance.
Although police previously said that they would not be investigating an alleged Christmas gathering which took place in Downing Street on 15 December 2020, the Met Police confirmed that they would be reviewing their decision to not investigate after a picture of Mr Johnson at the party beside an open bottle of champagne surfaced.
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