The Scottish politician - a former BBC journalist - had been seeking clarification about a report on former Culture Secretary Nadine Dorries.
At the time, Channel 4 had been put up for privatisation by Johnson’s government. This bid to take the broadcaster out of public ownership was subsequently re-examined by former PM Liz Truss and is understood to have been shelved by Rishi Sunak.
So what exactly has John Nicolson done - and why has it got him in hot water? Here’s what you need to know.
Who is John Nicolson?
John Nicolson, 61, is the SNP MP for Ochil and South Perthshire - a constituency that covers a largely rural area of central Scotland, including the towns of Kinross and Crieff.
Before being elected to Parliament in the 2019 General Election, Nicolson served as the MP for East Dunbartonshire - a seat he took from ex-Liberal Democrat leader Jo Swinson in 2015, who he then lost to in 2017.
Prior to politics, Nicolson had a career in journalism. He reported on BBC current affairs programmes like Panorama and Newsnight.
He has also presented BBC Breakfast and anchored ITV News. Nicolson’s career came after he attended the University of Glasgow and then spent several years in the USA as a Harkness Fellow and Kennedy Scholar at Harvard. During this period, he also worked as a speechwriter.
Since entering Parliament, Nicolson has become the SNP spokesperson for Digital, Culture, Media and Sport (DCMS) and sits on the DCMS committee that scrutinises the work of the government department of the same name.
What did John Nicolson do?
John Nicolson’s DCMS work is what has got him in trouble with the Parliamentary authorities.
The committee, which is chaired by Conservative MP Julian Knight, had produced a report on the behaviour of Nadine Dorries when she was Boris Johnson’s Culture Secretary (more on that below). This report did not recommend Dorries should be referred to the privileges committee - something which could have blocked her appointment to the House of Lords.
Nicolson sent a copy of the report to Lindsay Hoyle - the speaker of the House of Commons, who also plays a role in upholding its standards. When the SNP MP received a reply, he summarised it in a video on Twitter on 16 November.
The tweet, which is still on his timeline, shows Nicolson saying: "I sent a copy of the report to Mr Speaker, and he’s responded and I thought I should update you on what he said.
"He says that he’s considered my letter, but he’s decided to take no further action and not to refer Nadine Dorries to the Privileges Committee. In other words, she’ll suffer no consequences for what she’s done. And I thought you should know."
It sparked an immediate response from Hoyle, who lambasted the SNP MP for sharing details of the confidential correspondence. The Commons Speaker said Nicolson had "seen fit to give a partial and biased account of my letter on Twitter", had "misled the people of this country" and had "put me in a bad light with the people of this country".
Apologising to the Speaker, Nicolson said he was “deeply sorry” for upsetting Hoyle and insisted there had been “no malicious intent” in his summarising of the letter. However, he now faces his own investigation by the Parliamentary privileges committee.
On 23 November, backbench Conservative MP David Davis tabled a motion to debate Nicolson’s behaviour and accused the Scottish MP of attempting to blame the speaker for Dorries’ escape from censure.
"Nowhere in his filmed statement did he tell his followers that Mr Speaker was following normal precedent or normal procedure by accepting the will of the DCMS Committee,” Davis told the House of Commons.
"All of us in this House have a duty to uphold its rules and institutions, but by knowingly breaching the confidentiality of the Speaker’s correspondence he has done the opposite of that. This is a clear breach of our rules."
MPs voted by 371 to 16 to refer Nicolson to the committee.
Nicolson hit back at Davis, accusing the Yorkshire MP of not following House of Commons convention and “[scurrying] off before I could challenge him”.
What did Nadine Dorries do?
It all comes after Nadine Dorries was found to have misled the DCMS committee during an evidence session that took place on 19 May 2022.
The former Culture Secretary made claims about a Channel 4 documentary she had taken part in - 2010’s ‘Tower Block of Commons’ - in which she and several other MPs spent time living in deprived housing estates.
Dorries claimed the people she had stayed with for the programme were “actors” who “were not really living in a flat - they were not real”.
Her comments came at a sensitive time given the Johnson administration said it was considering the privatisation of Channel 4. The Conservative Party has taken against the broadcaster in recent years due to several incidents, including an occasion in the run up to the 2019 election when the party was empty-chaired by an ice sculpture for a debate on climate change.
Dorries’ claims were investigated by Channel 4 and the production company responsible for the show she took part in. They found no evidence to back up her claims about elements of the show being faked.
Despite being asked to correct the record on two separate occasions, the Bedfordshire MP refused. It led to an investigation by the DCMS committee to see whether she had made “an inadvertent mistake” or a “deliberate attempt to mislead the committee”.
It found she had made “groundless claims” and had used her Parliamentary privilege (i.e. rules that protect MPs from being legally challenged about comments they’ve made in the House of Commons) “to traduce the reputation of Channel 4”.
But the report did not refer her to the privileges committee because it said she was no longer Culture Secretary. Had she gone in front of the committee for breaching Parliamentary rules, her appointment to the House of Lords could have been blocked.