Judges on the UK Supreme Court will this week deliver their verdict on whether the Scottish Parliament can hold a second independence referendum without prior approval from Westminster.
Nicola Sturgeon instructed the Lord Advocate, Scotland's highest legal officer, to refer the case to the court in London in an attempt to break the constitutional log-jam.
Judges will rule on whether the Scottish Government's independence Bill relates to "reserved matters" - meaning it is outwith Holyrood's competence.
The decision is set to be announced on Wednesday at 9.45am. Dorothy Bain, the Lord Advocate, argued the Scottish Government's case at a hearing last month. referred the case to the court where she gave evidence last month.
She claimed an IndyRef2, which Sturgeon wants to hold on October 19 next year, would be advisory and have no legal effect on the union. James Eadie, representing the UK Government, argued to judges it was obvious the Bill related to reserved matters.
The judges' ruling could determine if the Scottish Government can legally hold a referendum without the consent of the UK Government - but it might not be as straight forward as that.
Holyrood given permission
The verdict the Scottish Government is hoping for it judges rule the independence referendum Bill in its draft form is within the competence of Holyrood.
It means Nicola Sturgeon could proceed with plans to hold an advisory vote on October 19 next year.
The First Minister previously said: "It is this government’s hope that the question in this Bill, proposing a referendum that is consultative, not self-executing, and which would seek to ascertain the views of the Scottish people for or against independence, will be deemed to be within the legislative competence of this Parliament.
"If that outcome is secured, there will be no doubt whatsoever that the referendum is lawful. And I can confirm that the government will then introduce and ask Parliament to pass the Bill on a timescale that allows the referendum to proceed on 19 October 2023."
Bill is reserved
The outcome many legal experts have predicted is the court rules the Bill covers matters reserved to the UK Government - and a Section 30 order would be required for Nicola Sturgeon to proceed.
A Section 30 order effectively loans powers to the Scottish Parliament from Westminster and was the mechanism used ahead of the 2014 referendum.
But Rishi Sunak and his three predecessors as prime minister have all ruled out a Section 30 order - instead arguing the result of the 2014 referendum must be respected.
If the court rules against her government, Sturgeon has threatened to make the next general election a "de facto" referendum on independence.
Sturgeon previously told MSPs: "If it does transpire that there is no lawful way for this parliament to give the people of Scotland the choice of independence in a referendum – and if the UK government continues to deny a section 30 order – my party will fight the UK general election on this single question –‘Should Scotland be an independent country’."
No verdict
The Supreme Court judges could announce they cannot at this stage make a ruling either way - a decision that would frustrate both sides of the independence debate.
UK Government lawyers argued during the court case in October that judges should decline to make a ruling on the issue because the legislation is still in draft form.
Too early
Another possible outcome from the Supreme Court could be the judges rule the application by the Scottish Government is too early to cast judgement on because the Bill is still in draft form.
Former First Minister and Alba Party leader Alex Salmond criticised the government over the case saying if it was successful the referendum would be a "glorified opinion poll".
Speaking earlier this year, he said: "If against all expectations the Scottish case was to prevail what exactly would have been won - the right to conduct a poll which the lord advocate's own submissions rested on the argument that it would have no practical effect.
"It would be a glorified opinion poll not an exercise in Scottish sovereignty."
To sign up to the Daily Record Politics newsletter, click here.
