MPs have voted to suspend Margaret Ferrier from the Commons for 30 days for breaching Covid lockdown rules.
The move will almost certainly lead to a by-election in her Rutherglen and Hamilton West constituency.
Ferrier won the seat for the SNP with a majority of 5,230 in the 2019 election but has been sitting as an independent since losing the party whip.
It would be an early electoral test for new SNP leader Humza Yousaf, with Labour hopeful of winning the seat.
Opinion polls have suggested that support for the SNP has fallen in recent months against a backdrop of Nicola Sturgeon resigning as first minister and party leader, and the ongoing police investigation into the party’s finances.
MPs voted by 185 to 40 in favour of suspending Ferrier from parliament for 30 days, with the suspension due to start on Wednesday.
She has already been ordered to complete a 270-hour community payback order by a court after admitting culpably and recklessly exposing the public “to the risk of infection, illness and death”.
She spoke in parliament while awaiting the results of a Covid test during lockdown in September 2020, then took a train home to Glasgow to avoid self-isolating in a London hotel after learning she had tested positive.
Ferrier has previously said she “deeply regretted” her actions but has so far refused to resign as an MP despite facing repeated calls to do so from many of her former SNP colleagues.
SNP MP David Linden said: “There must now be a by-election, which the SNP has been calling for since Ms Ferrier’s Covid rule breach first came to light in 2020.”
Scottish Labour has already selected Michael Shanks as its candidate ahead of the expected by-election.
Mr Shanks welcomed Ferrier’s suspension, and said it was a “disgrace” that she had “dragged this process out for so long, leaving her constituents unrepresented in parliament”.
Scottish Conservative MSP Graham Simpson repeated the party’s calls for Ferrier to stand down immediately, but said it “looks as though she will brazenly continue taking her MP salary until the bitter end”.
Of the 40 MPs who voted against the motion and opposed Margaret Ferrier’s suspension, 32 were Conservatives, two were DUP, two were Alba – Neale Hanvey and Kenny MacAskill – and one was Reclaim.
The Conservatives who backed her included former ministers David Davis and Jacob Rees-Mogg, and party grandees Sir Bill Cash and Sir Edward Leigh.
The result means a recall petition can now be started. More than 10% of registered voters in the constituency will need to sign the petition for a by-election to be held.
Ferrier was accompanied in the Commons by Conservative former minister Andrew Selous and SNP MP Carol Monaghan.
At one point, Conservative MP Daniel Kawczynski was seen walking to the opposition benches to shake her hand.
What did Margaret Ferrier do?
The Commons’ standards committee recommended in March that Ferrier should be suspended, with a independent expert panel later upholding the original judgement after she appealed against it.
The panel concluded that she had acted with “blatant and deliberate dishonest intent” and a “high degree of recklessness to the public and to colleagues and staff at the House of Commons”.
It added: “This is not one momentary error of judgment. It is a sequence of events amounting to a deliberate course of dishonest behaviour.
“She acted selfishly, putting her own interests above the public interest. There could therefore be no lesser sanction for this conduct.”
Ferrier took a Covid test on Saturday 26 September 2020 because she had a “tickly throat”. While awaiting the result she went to church on the Sunday and gave a reading to the congregation, and later spent more than two hours in a bar in Ayrshire.
She then travelled to London on a train that had 183 passengers on board on the Monday and spoke in the Commons later that day.
Shortly after leaving the chamber, she found out she had tested positive for the virus and took a train back to Glasgow the following day to avoid having to self-isolate in a London hotel room for two weeks.
She did not tell anyone about the positive test result until she was back in Glasgow.
Her appeal against the proposed 30-day suspension said it was too severe and that she was the victim of “double jeopardy” as she had already been punished by a criminal court for her offence.
A by-election in this seat would be the first electoral test for Humza Yousaf as SNP leader but it would also be a significant test for Labour leaders Sir Keir Starmer and Anas Sarwar.
They really need a win in a constituency that has flip-flopped between Labour and the SNP in recent years, to demonstrate momentum with a UK general election a year or so away.
For a by-election to be called, 10% of voters in Rutherglen and Hamilton West (around 8,000 people) must sign the recall petition demanding a vote.
This procedure has only been used three times before. It successfully triggered by-elections in Peterborough and Brecon and Radnorshire, with insufficient signatures being gathered to do the same in North Antrim.
Margaret Ferrier has not responded to media requests for comment but some of those who voted against her suspension believe this punishment, on top of 270 hours’ community service and public humiliation’ is “disproportionate”.