Yes, no, maybe– how the Supreme Court ruling will play out

Can we read anything into this? One reasonable inference might be that the court hasn’t struggled to reach a conclusion here. Many legal watchers reckon the Supreme Court will want this decision – like its ­controversial 2019 prorogation ruling – to be a unanimous judgment, without any ­inconvenient dissenters whose conclusions could be exploited by the losing side of the argument, whoever they turn out to be. A quick decision suggests Reed hasn’t had to spend long nights trying to hash out a judicial consensus with his colleagues.

Let’s wargame this: potential outcomes, potential responses, all the maybes. You might think the Supreme Court case could go one of two ways: either Reed and his colleagues will hold that Holyrood can go ahead with a second independence vote, or the justices will conclude that the ­Scotland Act prohibits MSPs from ­doing so. You’d be wrong. In fact, there are ­several ­different outcomes which might be ­announced, each with starkly different political ­consequences for the Scottish and UK governments.

It is worth quickly re-treading how we ended up here. The Scotland Act says that an MSP introducing a bill to ­parliament must make a statement that in their view it “would be” within devolved competence. When members of the Scottish ­Government introduce a bill, under the Ministerial Code, this statement is made on the Lord ­Advocate’s legal advice.

READ MORE: Michael Russell: We must defend ourselves against Unionist lies

Dorothy Bain KC takes the view that for a minister to make such a statement, they need to be satisfied not only that the ­proposal is arguably within competence – but that they are sure it “would” be to some degree of certainty. She isn’t sure.

Under section 29 of the Scotland Act 1998, legislation must not “relate to ­reserved ­matters”. These are listed in Schedule 5 of the 1998 Act and include the “union of the kingdoms of Scotland and England”. In determining whether or not provisions in a bill “relate to reserved ­matters”, the Scotland Act directs the courts to consider their “purpose and effect in all of the ­circumstances”.

So what is the purpose and effect of a referendum on Scottish independence? Should we limit our analysis to the ­limited legal effects of asking the public what they think? Or are the political consequences of a constitutional poll relevant too?

The oral hearing in October revolved around two key legal questions. ­Question one: under these rules, does Holyrood have the competence to legislate for an advisory referendum on Scottish ­independence? Question two: should the Supreme Court answer the first question at all?

Most of the UK Government’s case ­focused on persuading the five ­justices that they should turn the Lord ­Advocate away without a definitive ­answer. They argued the reference was incompetent under the Scotland Act, that the case was hypothetical and premature. Come back when Holyrood has passed a bill, James Eadie said, and the Supreme Court can consider its legislative ­competence then.

Their enthusiasm for this outcome seems mainly political to me. ­Returning the case to Holyrood unanswered would throw the Scottish Government straight back into the legal fankle this Supreme Court reference aimed to release it from. Even better from the opposition’s ­perspective, a rebuff from the Court has lively ­potential to be spun as Scottish Government incompetence, ­squandering scarce assets on legal battles during a time of financial constraint, and not even securing a definitive legal answer in the process. Above all: it would also buy the UK Government more time.

Outcome one is that the UK ­Government succeeds in this task, and the ­Supreme Court refuses to pass any ­comment on the substantive arguments about the ­limits to Holyrood’s powers to legislate for a ­second indyref. Back to square one.

If this comes to pass, there are ­basically three options open to the Scottish ­Government to get a referendum bill back before Holyrood. Either the First ­Minister would need to amend the ­ministerial code for a bill to be brought forward, the Lord Advocate would need to change her position on certifying the bill as within competence, or a backbench MSP could lodge a bill along the lines the Scottish Government has already drafted. Then it all starts all over again.

Alternatively, the Supreme Court might reject the UK Government’s threshold ­arguments and be prepared to help Bain out with a clear-cut answer one way or another on the substantive question of whether the draft Referendum Bill falls within Holyrood’s powers or not.

As some legal experts have pointed out, there’s actually a third potential ­outcome which will strike non-lawyers – and many lawyers, to be frank – as ­illogical. The ­Supreme Court might decide the Lord ­Advocate technically doesn’t have the power to refer the bill to them for ­decision, but nevertheless decide to give a decision on the merits anyway.

READ MORE: FM celebrates inclusion of loss and damage fund in COP27 agreement

This has happened before. In 2017, the Supreme Court held that the Northern Irish Human Rights Commission had no standing to challenge the ­continuing ­prohibition of abortion in Northern ­Ireland, but nevertheless concluded the blanket ban violated fundamental rights. Any judgment made on this basis would be obiter dicta – which is just legal ­jargon for not technically binding – but seems likely to be treated as gospel on the ­substantive issues anyway.

Let's say the case gets past the UK ­Government’s objections. Let’s say ­the Supreme Court decides to decide the big controversy in the case and give a view on whether the indyref bill is or is not ­within Holyrood’s legal powers. The Court’s analysis may be a clear yes, a clear no – or a maybe answer.

Say the Court concludes that the ­future of the union is subject to a sweeping ­reservation. Say they find that ­organising even an advisory referendum lies beyond Holyrood’s reach. For independence ­supporters, this is perhaps the ­starkest outcome. Holyrood will be left with no legal means of asking Scots whether they think independence is the form of government best suited to their needs.

There are no appeals to be made, no international courts to be petitioned, no international jurisdiction which applies here. Political pressure is all that remains. But politically, this outcome would pose fundamental questions about the state of the United Kingdom: how voluntary can a union be when you’re told there’s no way out? Independence supporters ­already feel strongly about this issue. How would the public react?

If the Scottish Government wins the case, by contrast, it will have secured a window of opportunity to pass legislation to set in train a second referendum on ­independence for October 2023. How might the UK Government ­respond? Accept the verdict, submit to the process, make an updated case for why we’re “better together” in 2022? Or – call me cynical – would it try to pauchle it in some way? Why assume any good faith or respect for democratic mandates, when every energy has been bent so far to blocking them?

READ MORE: Unison president Andrea Egan expelled from Labour Party

As former Whitehall mandarin Ciaran Martin points out, if the UK Government wants to, then it has a range of legal tools at its disposal to frustrate the process, ­including a Commons majority to pass legislation to block a second poll. ­Power devolved is power retained, after all. Would the new prime minister be ­tempted to use the power Westminster has retained to stymie a poll which the Supreme Court says is lawful?

Sir Keir Starmer seems like just the kind of guy to whip the Labour Party MPs to back this kind of scheme, cheered on by the party’s solitary Scottish MP Ian Murray. But would intervening in this way be seen as a bridge too far for Rishi Sunak?

Even if Holyrood legislation is within competence when MSPs pass it, the ­Scotland Act gives law officers scope for a degree of chicanery, preventing a ­Holyrood bill from being passed for royal assent while Westminster and ­Whitehall get busy.

They’ve used this pocket veto before on Holyrood’s EU ­continuity ­legislation. In the wake of a Supreme Court verdict in the Scottish ­Government’s favour, this manoeuvre would be bad-faith hackery of the first ­order – so there’s every likelihood it’s exactly what they’d do, making space for their colleagues in the Commons to get their Act together to subordinate the will of the Scottish Parliament to their own.

Alternative – less directly abrasive – strategies might include getting up the idea of a referendum boycott, and trying to popularise it through the more ­supportive organs of the press. Douglas Ross has been flying this kite for some time. This strategy would put, among other things, the BBC and Scottish Labour in a difficult position, which might suit the Tories. But what is the conceivable justification for boycotting a lawful referendum, voted for by a majority of MSPs, based on a clear manifesto mandate from the electorate last year?

Whatever happens next, Wednesday morning will be a hugely ­consequential moment for the Scottish ­independence movement and British ­constitutional history.