IN private, mischievous moments, I would occasionally refer to him as the “Grand Canyon”, a limp play upon his name.

Canon Kenyon Wright, that is; he who chaired the Executive Committee of the cross-party Constitutional Convention which paved the way to the present devolved Parliament.

He was a man of immense patience and perseverance.

It was his wont to respond to the Convention’s frequent bouts of partisan fury with a gentle Episcopalian smile. Nothing was more calculated to exasperate but somehow it worked.

The Grand Canyon was cited this week when Nicola Sturgeon set out her next referendum step. She quoted his most famous remark, a reference to Margaret Thatcher.

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“What if that other voice we all know so well responds by saying ‘We say no, and we are the state’. Well, we say yes and we are the people.”

It was powerful on the day of delivery and still neatly encapsulates the dichotomy which can arise when government and the governed appear to be in conflict.

Yet history teaches us – and Nicola Sturgeon well knows – that the Convention’s plan was implemented via a White Paper, a two-question referendum and Westminster legislation, driven by a majority Labour Government.

Popular opinion provided the motivation and the necessary assent. But the Parliament which emerged is a creature of statute.

That is why the First Minister’s primary aim is to strike a bargain with the UK Government to enable a further independence referendum to be put to the people.

She wants the PM’s consent. Not just to the process of the plebiscite but to the result which emerges. Without that consent, there would be no global recognition. No independence.

For me, that was always the key element in the Edinburgh Agreement signed by David Cameron and Alex Salmond. Both sides agreed to accept and implement the outcome.

Ms Sturgeon is adamant that she has a popular mandate to pursue indyref2. She says that arises from the 2021 Holyrood election when the SNP and Greens gained a majority, with both parties advocating independence.

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Certainly, it could be argued that the Tories regularly warned that a vote for the SNP equated to support for a further referendum and thus, potentially, for independence.

One might say they can scarcely complain now if the SNP, on returning to Holyrood power, take them at their word and pursue indyref2.

However, there is an alternative perspective. Yes, Nicola Sturgeon can say that she sought and gained the permission of the Scottish people to pursue independence.

She was returned to power and, in tandem with the Greens, wields a majority at Holyrood.

However, in that 2021 appeal for “permission” – the word used in the manifesto – she was standing for election to a Parliament which lacked the power to act on the issue of independence.

That same manifesto restated the SNP’s “firm and unequivocal” opposition to nuclear weapons. That does not mean that they gained a mandate to banish Trident from the Clyde.

Now, of course, the issue of independence is rather different. It is the SNP’s defining purpose. As Ms Sturgeon frequently comments, few can be in any doubt that the SNP wishes to dissolve the 1707 Union.

I think, then, that permission was indeed granted to pursue the topic, to the extent that the SNP out-polled other parties and were able to assemble a Holyrood majority comprising supporters of independence.

However, I also think that the legal mandate is doubtful. Further, I think it likely that the UK Supreme Court may well reach a similar verdict: that the constitution is reserved to Westminster.

To be fair to Ms Sturgeon, her statement this week explicitly accepted that there was a legal question mark.

Hence the referral, via the Lord Advocate, to the Supreme Court, deliberately short-cutting the legal challenges which would have arisen in any case had she introduced a Referendum Bill at Holyrood, rather than simply publishing it in draft.

If that fails, she says would turn the next UK General Election in Scotland into a “de facto” referendum on independence.

This multi-faceted announcement – which she delivered with confidence and force – is aimed at a range of targets.

She hopes to discomfit her Holyrood rivals; depicting Douglas Ross as taking orders from Downing Street and Anas Sarwar as lining up with the Tories to frustrate democratic choice. They say she is neglecting her duties.

Further, she hopes to placate restless elements in her own party. I think that is likely to succeed, at least in the short term. The zealous see action – and the prospect of an election cum referendum. What’s not to like?

Mostly, though, she hopes to apply pressure upon the Prime Minister. The SNP are building a narrative that the UK position is anti-democratic. We are beginning to hear talk of a Donald Trump stance, refusing to accept the outcome of an election.

So where next? I think it likely, on balance, that the appeal to the UK Supreme Court will fail. I think it probable that the Lord Advocate is, at best, sceptical as to the legality of Holyrood initiating a referendum.

Opposition parties have made much of that – and I understand why. However, it seems to me it is overtaken by the prospect of a UK Supreme Court ruling. The law will be clarified.

A “de facto” referendum, then, at the next UK election? Don’t see it. That would require the other parties to acquiesce in advance.

However, it would electrify the contest. Labour might be reluctant to be linked too evidently with the Tories in a defence of the Union. A big vote for the SNP would place substantial pressure on the incoming UK government.

Nicola Sturgeon knows that she needs a decision “de jure”. In law. In statute.

Put these points to senior Nationalists, as I did this week, and, understandably, they turn the question around. How, they say, are they to pursue the issue if not through the courts, including the court of public opinion?

However, I also discussed the topic with senior Tories. Albeit reluctantly, some say that Ms Sturgeon has energised her campaign, that it may not be feasible to reject a referendum indefinitely. We shall see.

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