A DISPLAY of cards hangs on the window of Ash Regan’s office in the Scottish Parliament. They’re from women’s groups and individuals thanking her for standing up for them during the Gender Recognition Reform debate.

“I wanted some of my SNP colleagues to have to walk by those cards every day and see that the women of Scotland are very angry with them,” she says.

She recalls one very senior male colleague in 2018 giving her a dressing down for signing a letter urging the Scottish Government to think carefully about gender reform. After the tirade, he’d said: “I just can’t understand why you did this.”

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When Ms Regan replied that she’d felt duty-bound to “for the women and girls of Scotland,” he had been dismissive.

“Ha, they won’t thank you for it,” he had said contemptuously.

Those cards are the proof that he was very wrong. “Nor were these groups government-funded,” says Ms Regan. “This was genuine and heartfelt. They were all grassroots organisations.”

She’s preparing to move to a slightly bigger office on a different floor. Having quit the SNP last week, she becomes Alba’s first MSP and, as such, the party’s leader at the Scottish Parliament. Within the Scottish Government, the move has not gone down well. Humza Yousaf said of his former ministerial colleague: “If she had principles, she would do the right thing and resign – but I have to say it is no great loss to the SNP.”

It was a vindictive and immature response, tinged with the bullying that some women inside the SNP say they faced in the Sturgeon/Yousaf era. Ms Regan though, refuses to be goaded.

“Look, Humza’s obviously got a difficult family situation right now with his in-laws trapped inside Gaza. I’m sure this isn’t typical of him as it was unbecoming of the office of First Minister. But I wish him well in his leadership of a party that I want to work with.”

Her friends tell a different story. They say that Ms Regan found his attitude “appalling” and pointed to the many times she’d ably deputised ably for Mr Yousaf at cabinet as his junior minister at Justice. It carried the imprint of Mr Yousaf’s predecessor, Nicola Sturgeon, who had conducted herself in a similar vein when Ms Regan resigned from her cabinet a year ago over aspects of GRR.

The First Minister’s response, though, might be considered statesmanlike compared with what emerged from the Scottish Greens. The SNP’s partners in government ran to a friendly newspaper to claim that their transgender staff feared for their safety if they were forced to share an office corridor with Ms Regan.

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This time she dispenses with the diplomacy and rectitude. “This is a parliament for grown-ups, and they should act like grown-ups. Some of those who claim to be disturbed at the prospect of my presence will have no problem sharing the women’s bathroom with me. So these claims are just performative and the sort of stuff you’d expect at the playgroup.

“More serious for me is how damaging the Scottish Greens have been in government. It’s beyond doubt that the Bute House Agreement has been damaging for the SNP. The policies that have caused the SNP the most trouble in the last couple of years are either policies that have come from the Scottish Greens or they’ve been implemented by them.”

“We were whipped to support a Green Minister [Lorna Slater] who has personally cost the taxpayer a lot of money over ill-considered policies, yet we threw out a highly respected member of our own group [Fergus Ewing] for opposing this. Now we’re told that independence isn’t even a red line for the Scottish Greens, according to Lorna.”

Is she surprised at some of the criticism, given that Ms Regan has merely moved from one pro-independence party to another?

“Alba is led by a person who was leader of the SNP when I joined it,” she replies. “It’s full of people who were friends, colleagues and activists whom I knew and worked closely with in the SNP. So, it’s not a defection; it’s more like a homecoming.

“I understand it’s a shock to some. People work hard for politicians to get elected, but there’s no point being at Holyrood if you don’t stand up for what you think is right.

“If you’d asked me this time last week If I’d be joining Alba I’d have sent no, not a chance. I only decided to go last Thursday. However it had become clear to me – especially in the last couple of weeks – that those who had expressed most concerns had decided it wasn’t worth the candle.

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“I thought that the Rutherglen defeat might have begun to concentrate minds. But the leadership was in full denial, claiming it was only an outlier when it was actually a wake-up call the leadership needed to heed. We had people going onto social media saying we had to distance ourselves from independence. It was utterly delusional.

“Inside politics, the party is the entity that you protect and you work for and you promote. Whereas I have a different view. I am country before party. I got into politics in the SNP because I wanted independence. I haven’t changed and my views haven’t changed. It just got to the point where I’d reached the end of the road with the SNP if I wanted to be true to those views.”

Yet what’s the point in joining Alba, I ask her. They’ve been pretty rubbish at elections and there’s no indication they’ll win anything significant any time soon. “I think Alba having a representative in here will be very significant,” she says. “It gives us an opportunity to showcase what we stand for and to have our voice heard.

“We’ve seen before what can happen where one party is in power and the rest have seemingly got no chance and then, when a few events unfold, there’s an extraordinary turnaround. I think Alba can make a breakthrough at the next Scottish election.”

She’d previously told me there were a significant number of SNP politicians who thought as she did about the party’s glacial approach to independence and their opposition to self-ID in the GRR Bill. Have some now indicated they’re likely to join her at Alba?

“No, not directly to me. But I know there are many in the party who are very disgruntled and that maybe around 14 or 15 MSPs are significantly on the edge. But dissent isn’t tolerated. It gets crushed. Sometimes MSPs don’t realise what power they have if they stick together on a principle.

“Tens of thousands of members have disappeared and several elected members have gone too. Clearly something is very wrong inside the SNP. I’d hoped there could be some unity of purpose among the dissenters, but in the end it seemed to evaporate. I think we could have forced change in the leadership’s thinking if we’d stuck together.

“I know I’ll be in a group of one for a while and that it may be lonely, difficult and challenging. But I’m optimistic that others will join me as certain events unfold. I feel a lot better, though, because I’m now free to talk about independence again. In the last few years that’s not been the case and there’s been no support from HQ or central office.”

She believes that Alba are far more attuned to the mood of the Scottish public, as the SNP had once been. But that her old party had been hollowed out by careerists whose views don’t align with the core beliefs of the SNP. “It’s sickening to see how activists who’ve given their lives and sacrificed careers being disparaged by those who’ve done little but exploit it.

“The SNP had no idea how unpopular gender reform was amongst the public. There was a feeling that it would just pass and people wouldn’t really care. I tried to warn them in cabinet when I used to deputise for Humza. On one occasion when I saw that gender reform was on the agenda, I told Nicola that campaign groups were actually forming to fight this. She flat out refused to countenance this. But these groups became a mighty campaigning force. I don’t think she or the party understood how determinedly ordinary females would organise and fight back.”

“Alba have the strongest position on GRR, which is why they have a lot of female activists. And it will be a better place for women because I can now say what I think on issues which I think affect women the most.

“A positive campaign will always defeat a negative one. If it’s two negative campaigns the most negative will win. The SNP has forgotten that. We won power by being relentlessly positive and friendly and people began to notice this. Now they’re doing the exact opposite.”

On the lift down to Holyrood’s reception area I’m accompanied by two Alba advisers. A senior SNP politician steps in and starts coming the plastic hard man. It’s a flavour of what Ash Regan has already encountered at Holyrood by some of her former colleagues and what now awaits her in the months ahead.