Boris Johnson has previously indicated he would be willing to speak to police investigating the ‘partygate’ allegations.
The initial findings of Sue Gray’s report were published on Monday (31 January) and revealed that police are investigating 12 events.
These include an event to mark Boris Johnson’s birthday in June 2020 and a “gathering in the No 10 Downing Street flat” on November 13 2020, the night Mr Johnson’s former aides Dominic Cummings and Lee Cain left their roles.
The May 20 2020 “bring your own booze” event in the No 10 garden which Mr Johnson attended for 25 minutes is also under investigation.
While the Prime Minister has said he would be willing to speak to the police, a sitting British Prime Minister has never been interviewed by officers under caution before.
So could Mr Johnson be placed under arrest? And would he face questioning by officers at a police station or Downing Street? Here’s what you need to know.
How would police go about questioning the Prime Minister?
A UK Prime Minister has never been interviewed under caution before.
However, Tony Blair was questioned by police - though not under caution - as part of the cash for honours scandal in 2006.
It was thought to be the first time a serving Prime Minister was interviewed by police carrying out a criminal investigation.
When police want to interview a suspect they have three choices, although one of them is quite rare.
Speaking to NationalWorld, barrister Andrew Keogh of legal news and awareness site CrimeLine explained the three options, and said an interview under caution - which doesn’t involve an arrest - was most likely in this case.
He said: “The first option is to arrest someone and take them under arrest to the police station that’s how serious crime is investigated.
“The second is to not arrest the person but interview them under caution - that is almost certainly what will happen here.
“And the third is again not to arrest them but instead of interviewing them face-to- face you are sent a questionnaire so you are sent written questions and asked to answer them. That’s sometimes used in health and safety investigations things like that - so we can rule that out.”
Would the Prime Minister have to go to the police station?
Mr Keogh said an arrest wouldn’t be on the cards, and that for an interview under caution it wasn’t likely Mr Johnson would be quizzed at a police station or Downing Street.
He said: “In order to arrest someone you need justification - it has to be proportionate which is not going to be the case here.
“So the Prime Minister, or anyone else they want to talk to, would be interviewed under caution and normally you would negotiate the location for that, so it’s highly unlikely to be a police station.
“It’s probably highly unlikely to be Downing Street as well. It would almost certainly be a neutral location where the Prime Minister could get in and out and police officers could get in and out without it creating any particular attention so as not to create a media circus.
“Where arrests are not being made, what we call a voluntary attendance its very much done by negotiation - everybody wants it done as expeditiously and quickly and conveniently as possible. “
Would there be special considerations for the Prime Minister?
If the Prime Minister was, for example, to be interviewed at a hotel, while many people might think that was preferential treatment - as voluntary interviews are done by cooperation it wouldn’t be out of the ordinary.
However, Mr Keogh said there would be things to consider with regards to an interview with the Prime Minister which would be different to other people.
He said: “There’s obviously different considerations with the Prime Minister, security considerations and things like that. He is obviously an important individual so whilst the starting point in the law is that everybody is treated the same, there are nonetheless conventions we have.
“So if we are dealing with senior politicians, police officers, royalty, diplomatic service - they are handled by different departments so it’s not going to be a probationary constable week one at Westminster police station. It’s going to be someone reasonably senior not necessarily deferential, but whatever you might think of the politics of it the Prime Minister holds an office and you accord the holder of that office respect that you might not accord to an alleged bank robber.
“There are these things around it, but not being treated particularly different to anyone else, but reflecting he has a status, he has an office, he comes with the baggage of security and you have to respect that and deal with all that.
“Other than that it would be an interview like any other.”
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