Lisa Cameron traces the beginning of the end of her career in the SNP back to a vote in the House of Commons in 2019 which extended abortion rights to Northern Ireland.

Her party, the SNP, had allowed a free vote on the legislation and Dr Cameron voted against, following her own conscience in doing so.

While opposed to abortion on religious and personal grounds - having experienced two late term miscarriages - and with abortion devolved to Stormont (which was not sitting at the time), Dr Cameron also believed her actions were in keeping with SNP thinking not to support Westminster interfering in devolved matters.

But her actions provoked a huge backlash among influential members of her party and, although she may have not realised it at th time, her rupture from the party had begun.

READ MORE: Lisa Cameron gives first major interview since defection

In her first in-depth newspaper since defecting from the SNP to the Conservatives in October last year - making history by being the first SNP MP to to do, the MP for East Kilbride, Strathaven and Lesmahagow, a mother-of-two reflects on the stormy period leading up to her switch, describes the impact of her growing estrangement with her party had on her mental health, and her new found sense of contentment as a Conservative MP.

"Abortion is an issue devolved to Northern Ireland. If you're saying other nations shouldn't interfere [with devolved issues] in Scotland, then perhaps we shouldn't be telling people in Northern Ireland what to do," says Dr Cameron, who was first elected to the Commons in May 2015, re-elected in 2017 and 2019 and was a senior NHS psychologist before entering politics.

"I spoke to MPs from Northern Ireland, I looked the polls which suggested people there did not want us to vote in that way. And also I am a Christian and I was told it was a vote of conscience and I could vote with my conscience. I had two traumatic miscarriages quite late on and it did make me think about those life issues. And I believe there should be a recognition of those issues in the Parliament."

READ MORE: Labour set eyes on Falkirk amid Matheson iPad saga

She adds: "I was told I could vote with my conscience. What happened afterwards was that people who vet prospective candidates came out publicly to say that I should not be a candidate because of the way I voted."

Her vote led to a backlash and then a backlash to backlash after churches and church members across denominations rallied to support her and condemn how she was being attacked.

She remembers that she was intending to stand as an SNP candidate in December 2019 but the vetting process was slow to approve her. It eventually did and she was able to stand and went on to win the seat for the third time.

The Herald: Dr Lisa Cameron MP being interviewed by The Herald's political correspondent Kathleen Nutt. Photo Colin Mearns.

"I think that showed that my constituents thought I could be a Christian in Parliament and that I could vote with my conscience on these issues," she says.

However, she adds the issue remained in the background when she returned to the Commons as an SNP MP.

Then, the Patrick Grady situation came along.

Mr Grady was the subject of a complaint by an SNP staffer who said the then SNP chief whip had made unwanted sexual advances towards him.

READ MORE: Labour set eyes on Falkirk amid Matheson iPad saga

Following an investigation by the Commons authorities, Mr Grady, MP for Glasgow North, was suspended from parliament for two days in 2022 for inappropriate conduct towards the young man.

He had the SNP whip removed for a period which was later restored.

The situation resulted in further tensions between her and the SNP when she spoke out at parliamentary group meeting to support the young staffer, she says.

Ms Cameron does not name Mr Grady when she looks back on the events from the time.

"I had worked as an expert witness for the Crown Office and Procurator Fiscal Service as a psychologist working with victims, and there was the situation with one of the SNP MPs who sexually harassed a member of staff," she says.

READ MORE: Ross joins Yousaf and Sarwar to oppose assisted dying bill

She adds that a meeting to discuss welcoming back Mr Grady she suggested she was not hugely in agreement about that prospect although she says "I wasn't saying I didn't think he should come back at some point".

After suggesting the group should support the member of staff she was met with a response which "was like tumbleweed going through the whole of the room."

As time passed, Ms Cameron says she felt a growing sense of isolation within the SNP parliamentary group.

The Herald: Dr Lisa Cameron said she received many letters from constituents concerned the double rapist Isla Byrson, pictured above, was initially sent to a women's prison.  

"People wouldn't speak to me. They wouldn't sit in the tea room with me. [The party] put me on the HS2 committee without telling me. I read the move in a newspaper," she recalls.

"I was told I had to move rooms. We are sending boxes for your things, I was told. I felt I was being shunned. I felt very alone.

"I was seeing the parliamentary welfare person at the time, which ended up being for a year. The staff there were very supportive and helpful and kept reassuring me that I hadn't done anything wrong. 

"I didn't move room as I told them the counsellor said it wouldn't be helpful to me to have that upheaval. So then they moved Patrick Grady next door to me."

READ MORE: Free tuition to be enshrined of constitution in independent Scotland

READ MORE: Lisa Cameron gives first major interview since defection

READ MOREEwing blasts SNP as he loses appeal against suspension

A third aspect leading to the final fracture of her relationship with the SNP was over the gender recognition reform bill going through Holyrood and the case of Isla Bryson, a double rapist initially sentenced to serve a sentence in a woman's prison

The GRR bill was designed to make it easier for transgender people to get a certificate in a new gender without having a medical diagnosis of gender dysphoria and to shorten the length of time trans gender people would have to live in their new gender. It also reduced the age people can apply to get a certificate from 18 to 16.

The bill was passed amid an SNP rebellion in Holyrood but ultimately blocked by the UK Government who said it was not compatible with equalities legislation which applied across the UK.

The SNP challenged the decision arguing Mr Jack was undermining the powers of the Scottish Parliament. The Court of Session last year ruled that Mr Jack's use of Section 35 of the Scotland Act was lawful. 

The Herald: Campaigners outside the Scottish Parliament while the GRR bill was being debated.

Ms Cameron says: "As a party we began to talk more about gender issues than independence. I started getting letters from constituents about Isla Bryson. 

"I had done work as a psychologist in a women's prison and I realised that many women who go to prison have a history of trauma and are very vulnerable. The party became very dogmatic and autocratic. It felt  that you couldn't have an independent thought."

She says that as a result of her constituents concerns over the Bryson case, she wrote to Scottish Secretary Alister Jack.

"I asked him if it was possible to look in a way which addresses my constituents concerns but doesn't impact on the devolution settlement. It was quite a measured letter."

But when the story broke, Ms Cameron says she received "more horrendous abuse" from she says SNP supporters and "cybernats".

As a result of the experiences she says she began to question her belief in Scottish independence - the very idea that had made her join the party the day after the independence referendum in September 2014.

She has since come to the view that she no longer supports independence.

Ultimately, events led to her having a meeting with the Prime Minister, following which she made the decision to cross the House to the Conservatives, though not before discussing it with her family.

As revealed in The Herald yesterday, the meeting with Rishi Sunak was cordial and she describes him as being "very empathic" and wanting to listen. 

She insists no deal was done for her to be offered a seat in the Lords in return for moving to the Tories.

"I didn’t discuss anything about the Lords with the PM and I was not offered to go House of Lords to move party," Ms Cameron told the Herald on Sunday.

"That was not part of the discussion I had with the Prime Minister and it is not something I would expect at all."

Shortly after meeting the Prime Minister she discussed the prospect of defecting to the Conservatives with her family. Her Tory supporting mother was delighted.

The move was announced days before the SNP's annual conference.

It was a decision which left her and her family in further turmoil and having to stay in a safe house after serious threats of violence. She says despite the upheaval she continued to work through the crisis.

"I had a period were I was in a safe place, but I still answered my emails and managed to get cases resolved," she says.

She adds ahead of her conversation with the Prime Minister, while still an SNP MP, she had considered stepping down from Parliament. However, the SNP were reluctant for her to resign.

She points to that reluctance when I ask her about the First Minister Humza Yousaf's demand that she step down after she switched to the Conservatives and for a by election to be held. She believes the SNP would not have actually wanted a by election in her seat soon after badly losing the one in nearby Rutherglen and Hamilton West.

Six months on from becoming a Tory MP, she is no longer in counselling, is off antidepressant and is busy with her constituency work. Since November she has also been a parliamentary private secretary to Mr Jack.

Earlier this month her work in the area of disabilities was recognised with the first annual Disability Entrepreneurship Lifetime Achievement Award.

The award from Universal Inclusion, which honours outstanding contributions and achievements of disabled entrepreneurs and advocates, was presented by Minister for Disabled People, Mims Davies, in the House of Commons.

“I have never been busier as an MP. I have a fifth more emails than I’ve ever had. People have not stopped coming to me as a Conservative MP," she says.

“Business have been in touch who weren’t in touch before. I’ve had constituents who are Conservative who got in touch who didn’t before, and I still hear and represent my SNP supporting constituents.”

Labour and the SNP say the UK has been badly served by 14 years of Conservative governments pointing to increasing inequality, rising poverty and slow economic growth.

What would she say to their criticisms? 

"The Prime Minister who was chancellor during covid19 oversaw the largest programme to support people across the UK with furlough payments than has ever happened before, to save jobs and keep the economy alive," she says.

"This in combination with the Covid 19 vaccination roll out has supported everybody at a time of crisis."

She then rounds on the SNP.

"The UK Government are now lowering taxation and interest rates are falling, whilst comparatively  in Scotland we are becoming the highest taxed part of the UK, hurting hard working families. SNP are progressively ruining Scotland’s economy, businesses and local services in comparison and this is obvious to people everywhere across the country."

Ms Cameron is not standing for re-election and believes the SNP will not win her East Kilbride seat at the general election, expected later this year, believing that "Scotland has turned a page on nationalism".

She says she is happy being a Conservative MP, continuing to work on disability issues in parliament and she looks forward to return to her work in the NHS as a psychologist when her almost ten year career as an MP to come to an end.

"I have always been someone who likes to build a consensus, to reach agreement. I think my politics is about how we get policies that help people rather than tear strips off each other," she says.

"I feel more naturally myself. I don't feel I am putting myself into something where I just don't fit. I always had friends [on the Conservative benches] because I have worked cross party. I feel the opposite of [being alone]. It's been a different parliament for me."

She adds: "I am certainly contented now and I feel it is where I belong - I can achieve my disability work in parliament and be myself - a Christian, a woman in politics and most importantly a mother."