Analysis: Dry and methodical, the Supreme Court prepares to shape Scottish political history

It didn't take long for the Supreme Court referendum battle to plunge deep into the woods of complex legal and constitutional arguments.

Lawyers manoeuvred thick folders stuffed with papers and there were references to previous cases involving unlikely topics such as the display of tobacco products and asbestos-related medical costs in Wales.

“Electronic folder, page 88, and paragraph six through to 46, pages 89 to 103,” directed Dorothy Bain, the Lord Advocate, as she put forward one particularly technical argument.

At times it was fascinating. At other times, not so much.

Picture: Andy Buchanan

But the decision this court reaches – carefully, methodically, authoritatively – could well shape the political debate in Scotland for years to come.

Nicola Sturgeon wants to hold a second independence referendum on October 19 next year.

The UK Government will not agree to this, making a repeat of 2014 impossible.

If the court rules that Holyrood has the power to legislate for another vote without UK approval, the First Minister will seek to push ahead with an advisory referendum.

In just over a year, the people of Scotland could once again be choosing between Yes and No, independence and staying in the UK.

If the court battle does not go her way, Ms Sturgeon intends to use the next general election as a “de facto” referendum.

This sounds potentially messy, and is best viewed as a strategy to pile more pressure on UK ministers rather than anything more concrete.

If it doesn’t work, the independence debate could stall, with no viable way forward.

And even if it works on its own terms, the road ahead is anything but smooth.

In short, there are many unknowns and forking paths ahead.

The Supreme Court could not only settle a “festering issue” that has long troubled legal minds, but its decision will have a real impact on what happens next.

Its five judges have two matters before them.

The first is whether the court has “jurisdiction” to determine the issue, and whether it should make a ruling on it.

Interestingly, the judges had a lot of questions for Ms Bain relating to this.

Part of the UK Government’s argument is that the case should be thrown out because it is premature. The relevant legislation hasn’t even been introduced to Holyrood yet.

The second question is whether the Scottish Government’s proposed referendum legislation relates to matters reserved to Westminster.

There are differing interpretations of the Scotland Act 1998, which says a provision is outside the Scottish Parliament’s legislative competence if it “relates to” reserved matters such as the Union or the UK Parliament.

Ms Bain argued an advisory referendum has no automatic legal consequences and would simply seek to test public opinion.

The political fallout is irrelevant to the court, she said.

It remains to be seen whether the judges agree.

Supreme Court president Lord Reed said the hearing “is the tip of the iceberg”, and with more than 8,000 pages of written material to consider, it is “likely to be some months before we give our judgement”.

Depending on what “some months” turns out to mean, that could present another problem for Ms Sturgeon. That October referendum date might look increasingly impossible.