Nicola Sturgeon promising she won’t mention independence during a coronavirus briefing is like me promising I won’t mention independence during a column about independence. It’s not going to happen. And so it was no surprise at all when the First Minister diverted from last week’s Covid briefing to talk about the constitution just after promising she would not be diverted from last week’s Covid briefing to talk about the constitution. But let’s forgive her brazenness for once, shall we, because what she actually said about the constitution was interesting, and it matters.

The subject at hand, as you’re probably aware, was when and if another referendum on independence should be held and specifically what level of public support would justify it. According to the Scottish Secretary, Alister Jack, a referendum should only happen if 60% of Scots consistently supported it. Ms Sturgeon, on the other hand, said Mr Jack was making up the rules as he went along. “We have constitutional rules that are pretty well established in a democracy,” she said. “If a party wins an election on a particular proposition they should get to implement that proposition.”

Now, I know there are a lot of people who will agree with that, but most people are also living with one of the consequences of the election-winning principle, which is Brexit. You also need to look at what Ms Sturgeon actually means by winning an election. The SNP did end up with a record number of the constituency seats in May (85%) and, even after the adjustment for the list votes, the SNP and the Greens have 72 of the 129 seats (or 55%). But they have a majority of the seats based on a minority of the votes. The SNP won 47.7% of the constituency vote and the Greens took a truly pathetic 1.3% – or 49% combined. The Tories, the Lib Dems, and Labour, on the other hand, took 50.4%. Seen in that way, the figures look much less like a win, don’t you think?

We should also look at what Mr Jack actually meant when he talked about 60% support for a referendum because what he was referring to (not very well in my opinion but we’ll get to that) was the concept of a “settled will”, or a big and consistent majority for change, such as the one that existed in the 1990s for devolution. Back then, there was a settled will across all classes, cultures and parties and when the referendum happened, support for the parliament was 74.3%. In that sense, the referendum was unnecessary: it was just a way to confirm a change that had already happened and, before the ’97 election, a way for Tony Blair to combat accusations that a vote for Labour was a vote to break up Britain.

But if we accept that there should be a settled will before major constitutional change, we need to decide what that actually means, and 60% support for the change among voters seems like a fair hurdle. Indeed, in private, senior figures in the SNP used to see 60% support for independence as the level they needed to reach before another referendum was held, although, admittedly, for them it's all about trying to make sure they win rather than necessarily establishing a settled will in as fair a way as possible. Even so, 60% does at least represent an actual majority rather than 47.7%, which is what the SNP got in May.

The problem with Mr Jack’s comments on the subject is that he was saying something rather different. The concept of the 60% rule (even though you could argue the case for 70%) is that 60% of the population support the change you’re proposing, such as independence. But what Mr Jack was suggesting was that a referendum would only be held if 60% supported the referendum itself. Only if a big majority of people wanted the vote would the vote go ahead.

This, I think, is going too far and is in danger of straying into the kind of jiggery-pokery that happened over devolution during the 1979 referendum. Infamously, the Labour government of the time said the result would only stand if it was supported by 40% of the total electorate (irrespective of how many people voted) and everyone could see what they were up to. They were establishing a target that was virtually impossible to achieve with the aim of preventing devolution happening.

To be fair to Mr Jack, he is not suggesting something quite as perverse as that, but 60% support for a referendum does have the look of a hurdle that is set deliberately high. If you look at the polls, even when support for independence itself is hitting unprecedented levels, support for calling another referendum is much lower and is usually bumping along at thirty-something per cent. Partly, this is because many of those who support independence can see that holding a referendum right now, in the aftermath of a pandemic, is a bad idea. But even when the pandemic is long gone, there will be others who would consider voting Yes but just can’t face the idea of another experience like 2014. And who can blame them.

No doubt the Scottish Secretary has been following all these polls and, let’s face it, probably suggested the idea of 60% support for a referendum because he believes the support will never get that high and he’s probably right. But 60% support for independence is another matter: there was a time, late last year, when it was as high as 58%. But the point is it didn’t last. What the 60% rule requires – entirely fairly – is that support for change is large and consistent and that a majority of people – a real, consistent, lasting majority of people – want the change.

The problem for the SNP is that we are nowhere near meeting that test yet, but it would be to their credit if they publicly acknowledged the validity of the test. With the exception of hardcore nationalists and hardcore unionists, most Scots would accept a profound change to our constitution if it was based on a profound change in public opinion rather than, say, 47.7% support in an election, or a pact with a minority party, or, God forbid, a 50.00001% win in a referendum. Yes, Mr Jack’s version of the 60% rule may be a little devious and unacceptable. But the principle of a settled will is still the only fair and democratic way to change the settled nature of our country. The SNP just hasn’t come to terms with it yet.

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