Dr Lisa Cameron: SNP MP for East Kilbride defects to Tories after claiming 'toxic and bully treatment'

SNP MP Dr Lisa Cameron has quit the nationalists and dramatically defected to the Scottish Conservatives as the pressure piles on Humza Yousaf.

The MP's change of party comes on the day she was facing a selection battle to be the candidate in the west of Scotland seat of East Kilbride, Strathaven and Lesmahagow. Prime Minister Rishi Sunak said he is “delighted” at her decision while the SNP called on her to “do the right thing” and allow a by-election to take place.

The Scottish Daily Mail has reported she had complained of “toxic and bullying” treatment within the SNP. The MP said she has received support from Prime Minister Rishi Sunak after her mental wellbeing deteriorated in recent weeks, but has had no contact from the SNP leadership.

The defection is likely to pile more pressure on under-fire SNP leader Yousaf, who is preparing for his party conference this weekend after Labour won the Rutherglen and Hamilton West by-election. It comes after a slew of SNP figures, including Nicola Sturgeon, have been arrested during a police investigation into the party's finances.

Dr Cameron previously said she was a victim of “group bullying” at Westminster and suffered panic attacks as a result. She claimed she was shunned by other SNP MPs at Westminster after challenging the support given to former chief whip Patrick Grady – who was suspended from the House of Commons and apologised in Parliament after being found to have acted inappropriately towards a party staffer aged 19.

A Parliamentary report into Grady's behaviour found he “made an unwanted sexual advance to the complainant that included the touching and stroking of the complainant’s neck, hair, and back”

Last month, it emerged a Scottish Government minister had backed another party worker, Grant Costello, who was challenging Dr Cameron to be the next SNP candidate in her seat at the general election.

What did Dr Lisa Cameron say about 'toxic and bullying' claims?

Dr Cameron told the Scottish Daily Mail: “I do not feel able to continue in what I have experienced as a toxic and bullying SNP Westminster group, which resulted in my requiring counselling for a period of 12 months in Parliament and caused significant deterioration in my health and wellbeing as assessed by my GP, including the need for antidepressants.

“I will never regret my actions in standing up for a victim of abuse at the hands of an SNP MP last year, but I have no faith remaining in a party whose leadership supported the perpetrator’s interests over that of the victim’s and who have shown little to no interest in acknowledging or addressing the impact.

“It is also true that I have received no contact from party leadership in the past weeks, despite members of every other main political party contacting me to offer support and compassion during what has been an extremely difficult time.”

She praised Sunak’s “positive” leadership, saying it contrasted to that of the SNP group. Dr Cameron also said the SNP’s founding cause of Scottish independence had led to “significant division” in families like hers.

What has Rishi Sunak said about the defection?

Sunak reacted to her decision saying: “I am delighted that Lisa Cameron has decided to join the Conservatives. She is a brave and committed constituency MP. Lisa is right that we should aim to do politics better, with more empathy and less division and a dedication to always be doing what we think is right.

“I look forward to working with her on the disability issues she has championed so passionately in Parliament, and on the issues that really matter to her constituents in East Kilbride, Strathaven and Lesmahagow.

Dr Cameron should 'step down to allow a by-election'

An SNP spokeswoman said her constituents would be “appalled” that they now had a Conservative MP. She said: “Lisa Cameron should now do the right thing and step down to allow a by-election.

“Her constituents elected an SNP MP, not a Tory, and they deserve to have the democratic opportunity to elect a hard-working SNP MP who will put the interests of Scotland first. On a personal basis, we wish her well.”

While Ian Murray, Labour’s Shadow Scottish Secretary, said Dr Cameron's constituents have been "let down by a SNP MP who has shown her true colours".

He said: “On Monday, while the new Labour MP Michael Shanks will be taking his oath on behalf of his constituents, Lisa Cameron will be crossing the floor to join the Tories. It’s clearer than ever - vote SNP, get Tory or vote Labour and get the change our country deserves.”

Conservative MP John Lamont posted a “warm welcome” to his new colleague on Twitter, while Tory MSP Murdo Fraser said: “As the SNP continues to implode, this is another signal that ⁦@ScotTories are making gains at their expense.”

Scottish Conservative leader Douglas Ross said on Twitter: “It’s great to have Lisa Cameron on board. The @ScotTories will stand up for everyone who has been forgotten by the SNP to get the focus on to Scotland’s real priorities.”