“IT’S a TERF landslide”. The results of the Scottish National Party’s NEC elections aroused some anger in the darker regions of Twitter. This was largely because of the elevation of so-called “gender-critical” women, like Joanna Cherry MP – called TERFS because they oppose Nicola Sturgeon’s plans to allow people born male to self-identify as women. But the rise of Ms Cherry, who many see as a future leader of the SNP, poses a more immediate challenge to Ms Sturgeon’s safety-first route to Indyref2.

at she would only call another independence referendum if she had the agreement of Westminster, in the form of a Section 30 Order granting Holyrood the power to hold such a ballot. This was the route pursued by Alex Salmond via the Edinburgh Agreement of 2012. But the obvious problem is that Boris Johnson has made clear that, even if the SNP wins another landslide at the Holyrood elections in May, he will not authorise another Section 30.

He insists that the First Minister had agreed that the 2014 referendum would be a “once in a generation” consultation and a generation isn’t up yet. This has become known as the “Boris veto”. And Ms Cherry’s many supporters are not having it. They want a Plan B – an alternative route to Indyref2.

Ms Sturgeon has had to respond to the tide of opinion in the party this week by conceding, for the first time, that she is “not ruling out” an alternative if and when Mr Johnson says, as Theresa May did in 2017, that “now is not the time”. Mind you, she isn’t ruling anything in either. The SNP leader doesn’t want a referendum unless it is legally binding. She is a lawyer, after all.

Some in the party think she should go ahead with an advisory referendum; others argue for an illegal secessionist referendum, Catalonia-style. For her part, Ms Cherry wants to use the power of the law to force the Prime Minister’s hand. She has a formidable track record of doing precisely this. During Brexit, she was one of the leading figures in the court campaign against Mr Johnson’s refusal to extend Article 50.

How long ago that all seems – yet it is only a year since Ms Cherry and Jolyon Maugham QC raised an action in the Court of Session, arguing that it would be unlawful for Mr Johnson to suspend Parliament in the run-up to Brexit. They won that case on appeal, and the matter went to the Supreme Court, where of course, the “spider lady” Lady Hale ruled that the PM had indeed acted unlawfully.

The court ruling was a huge embarrassment to the Government. But it also established an important legal precedent. Hitherto it had been thought that the courts had no right to challenge the political decisions of an elected, responsible government. This has been the view of constitutionalists since the days of A V Dicey in Victorian times. It was why the Court of Session judges initially rejected the Cherry-Maugham case. The Supreme Court ruling implied that, in future, governments would have to accept rulings of the courts. They can no longer argue that the Prime Minister is, effectively, above the law of the land.

The Appeal Court said Mr Johnson’s prorogation was unlawful because “it had the purpose of stymying parliament”. He had suspended Parliament in order to circumvent the Benn Act requiring him to write to Brussels to extend the Brexit transition period beyond October 31, 2019. Parliament must always be obeyed. Supporters of a legal Plan B believe that a vote of the Scottish Parliament, after a General Election in which a referendum was a manifesto pledge, could be seen to have equal legal force.

Another constitutional expert, Aidan O’Neill QC, said earlier this year that, in his opinion, the Scottish Parliament might already have a legal right to hold a referendum on independence. He argued that the principle of democratic accountability, which was deployed against Mr Johnson’s suspending Parliament last year, could be used to justify indyref2.

Holyrood does not have the right to declare actual secession, UDI, but that doesn’t mean it lacks the right to ask the Scottish people to declare their wish to be independent. Mr O’Neill was the first to admit that this had to be tested in court.

That is where the Cherry strategy, outlined in a speech in Wales last week, begins. Assuming that Mr Johnson rejects Ms Sturgeon’s demand for a Section 30 order, Ms Cherry thinks the Scottish Government should move a bill for a referendum anyway, and defy the UK Government to rule it “ultra vires” or beyond the power of Holyrood. This would be fought out in the Court of Session and ultimately in the Supreme Court in London.

I doubt myself whether the Supreme Court would welcome this. It is the highest court in the United Kingdom, after all, and isn’t in the business of abolishing the Union. In its ruling on the Miller Case in 2018, the judges said that the Westminster Parliament is sovereign under the 1998 Scotland Act and can over-ride any vote of Holyrood. For the democratic accountability argument to succeed, Westminster would surely have to pass a Section 30 Order, and with a Tory majority of 80, that just isn’t going to happen.

However, the Supreme Court might agree that Holyrood has the power to ask the people what constitutional future they would favour. Such a referendum would not make Scotland independent. But a substantial Yes vote, after this court battle, would certainly put moral and political pressure on the UK Government. It might force Mr Johnson to the negotiating table, if not on independence, then certainly on enhanced powers for the Scottish parliament.

Of course, it could go both ways. In a post-Covid climate, Scottish voters might resent having to go through another divisive referendum – especially one which doesn’t even have the force of law. Ms Sturgeon might agree with them. But one thing is certain: with Joanna Cherry QC breathing down her neck, doing nothing is no longer an option.

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