Boris Johnson has admitted he inadvertently misled parliament in a series of statements he made in relation to partygate.

But setting out his defence ahead of an appearance at the privileges committee tomorrow, the former prime minister insisted his comments were delivered “in good faith” and that he believed them to be true at the time.

It’s his response to allegations he broke the Palace of Westminster’s rules, as set out in a book called Erskine May’s Parliamentary Procedure, which says: “The Commons may treat the making of a deliberately misleading statement as a contempt.”

Here we take a look at each of the three Commons statements the committee is investigating and set out Mr Johnson’s explanation for how he played by the rules:

Alleged rule breach 1

Date: 1 December 2021

What Boris Johnson said: “What I can tell the right honourable and learned gentleman is that all guidance was followed completely in Number 10.”

His defence: Mr Johnson said he became aware the Daily Mirror was planning to run a story on alleged lockdown breaking at a gathering on 30 November 2021 – around the time of the Omicron variant and new restrictions being voted through Parliament.

He said his director of communications, Jack Doyle, came to see him that evening about an email the paper’s political editor had sent – his diary recorded this meeting between 6pm and 6.05pm – making allegations about four parties.

“I did not see the email myself and the only event I can recall Jack mentioning in any detail was the one held in the press office on 18 December 2020, which I had not attended,” said the then PM.

“The email mentions two other events – on 13 November 2020 and 27 November 2020 – which I do not recall Jack bringing up but I accept that he may have. These were ones that I had attended.”

But he said had Mr Doyle mentioned them, he would have been “confident” they had complied with the COVID rules at the time due to his own attendance.

Back to 18 December, and Mr Johnson said he felt it was “implausible” the COVID rules had been broken.

After hearing Mr Doyle’s description of the gathering, Mr Johnson said he believed it.

And in his evidence to the privileges committee, he sought to add context to the experience of Downing Street staff.

For the then PM, drinking wine at a person’s desk was not rule breaking under the rules he had brought into force.

The press was briefed “COVID rules were followed at all times” and Mr Johnson said he “did not anticipate that this would be a big story”, even saying he was “surprised” when Labour leader Sir Keir Starmer raised it at Prime Minister’s Questions on 1 December.

Sir Keir asked: “As millions of people were locked down last year, was a Christmas party thrown in Downing Street for dozens of people on 18 December?”

Mr Johnson responded: “Based on the conversations that I had had the previous day and that morning… What I can tell the right honourable and learned gentleman is that all guidance was followed completely in Number 10.”

And while he said he meant to repeat the exact line given to the Daily Mirror the night before, he said he did believe all guidance had been followed based on his understanding of the rules.

He said: “I did not mean that social distancing was complied with perfectly in Number 10, but this was not required by the guidance.”

He said he “relied on my knowledge of those events for the periods which I attended”.

He also added: “Number 10 and the Cabinet Office are very large departments. I believed that if anyone witnessed something that they considered to be illegal or contrary to guidance, I would have been made aware of it.”

Evidence supporting him: Mr Johnson said it was fair to accept he believed everyone was following the rules and guidance because “this belief was shared by many others” – pointing to six individuals.

The names of three of them – all Number 10 officials – have been redacted, but his principle private secretary, Martin Reynolds, his official spokesman (later promoted to director of communications) James Slack, and Mr Doyle were named.

In his written evidence to the committee, Mr Reynolds wrote that he and others “involved in organising and attending the gatherings” believed they were following regulations and that decisions “were taken in good faith and were reasonable on a common-sense reading of the relevant regulations”.

He also said he believed “all senior staff in Downing Street”, assumed the events were lawful too, both political staff and civil servants, saying: “They spoke at, attended or were aware of some, or all, of the gatherings. The attendees included some of those responsible for the regulations. I believe in-house lawyers were copied in to some invitations.”

In an interview that came as part of Sue Gray’s partygate investigation, Mr Slack said: “I honestly don’t think that anyone who was in that room was breaking any rules. They were with their colleagues who they sat with all day every day for 12 hours.

“Were there additional elements to that? Yes. That was a reflection of the specific circumstances of the end of the year. Everyone in the office knew that they were public servants and wouldn’t have done it if they thought they were breaking rules.”

Mr Johnson also cited a WhatsApp conversation between him and Mr Doyle on 10 December, where the then PM said: “Is there a way we could get the truth about this party out there.”

In conclusion, Mr Johnson said: “In hindsight, I accept that my statement to Parliament on 1 December 2021, although reasonably and honestly believed at the time, did mislead the House.

“If I had been aware of this information, I would obviously not have stood up in Parliament and said what I said.”

Alleged rule breach 2

Date: 8 December 2021

What Boris Johnson said: “I repeat that I have been repeatedly assured since these allegations emerged that there was no party and that no COVID rules were broken – that is what I have been repeatedly assured.”

His defence: The day before Mr Johnson made this statement to the House, the footage of Allegra Stratton joking about a lockdown event taking place on 18 December 2020 in Downing Street was published by ITV.

The then PM said he had “not previously seen this video” and it caused him “immediate concern”, but in the evening Mr Doyle sent him a WhatApp saying: “I think you can say ‘I’ve been assured there was no party and no rules were broken’.”

Mr Johnson said he later called Mr Slack “who I regard as a man of great integrity and who was in the building on the evening of 18 December 2020”, and he also confirmed that the rules had been followed.

But as he “remained concerned”, he decided he needed to commission an investigation to “find out precisely what happened at the event in question”, and spoke to cabinet secretary Simon Case that night, asking him to carry it out.

Mr Johnson received another WhatsApp from Mr Doyle the following morning with a proposed wording for a statement: “I sought and was given reassurance no rules were broken and no party took place.”

The details were thrashed out in an email chain “which involved numerous civil servants and advisers”, and after a large meeting, a statement was agreed.

The PM went to the House and ahead of PMQs said: “I repeat that I have been repeatedly assured since these allegations emerged that there was no party and that no COVID rules were broken. That is what I have been repeatedly assured.”

He also confirmed the independent inquiry, which was due to be led by Mr Case – before he was later found to have attended a gathering and recused himself.

In his evidence to the committee, Mr Johnson said: “This statement was entirely accurate, and I do not believe that the House has been misled by it.”

He said the statement “related exclusively to the event on 18 December discussed by Ms Stratton – “the focus of the media storm”.

And he said he told MPs “what I honestly believed based on my own understanding, and what I had been told by others – but I acknowledged that the truth would be established independently, and that I might subsequently be found to have been wrong”.

Evidence supporting him: First, Mr Johnson included Mr Doyle’s interview with Sue Gray over what he had told the PM about the events.

Asked if he gave the repeated assurances, Mr Doyle said the pair had a conversation “and the only thing I said to the PM was that I didn’t regard this as a party and we didn’t believe the rules had been broken and that’s what we said at lobby – the rules is a judgment for others, it was not an organised party”.

The then PM also said the “repeated assurances” he was given were witnessed by two Tory MPs – Andrew Griffiths and Sarah Dines.

And Mr Reynolds said: “I believe that reassurances were provided by some of the senior communications team staff who were present at the event, including Jack Doyle.”

Alleged rule breach 3

Date: 8 December 2021

What Boris Johnson said: “No but I am sure that whatever happened, the guidance was followed and the rules were followed at all times.”

His defence: In the same PMQs sessions, Labour MP Catherine West asked Mr Johnson whether there had been a party on 13 November amid rumours of a fresh story.

It was later confirmed a leaving party did take place in Downing Street on that date – though rumours of a “victory party” taking place in the PM’s flat the same day Dominic Cummings left his post have been denied.

Replying to the MP’s question though, Mr Johnson said: “No but I am sure that whatever happened, the guidance was followed and the rules were followed at all times.”

In his evidence, Mr Johnson said: “I appreciate that the meaning of this statement is not entirely clear. At the time, I did not know what event Catherine West MP was referring to, and it remains unclear.”

He revealed he did attend two events on that day, but again said he believed he had acted in line with the rules.

Evidence supporting him: Again it is principle private secretary Mr Reynolds who Mr Johnson uses to back up his claims.

In his statement to the committee, Mr Reynolds said: “I believe that at the time the story broke in November 2020 there was a collective belief in the Cabinet Office and Downing Street that we had operated within the rules during lockdown and that any events which took place had been legitimate, work-related gatherings”.