THE BRITISH government needs to provide clarity on how the constituent parts of the UK can leave the union, the president of the Scottish National Party will tell tomorrow night's Ireland's Future event in Belfast.
Michael Russell, who will deliver the keynote address at the sold-out Ulster Hall event, said there needed to be "an understanding of how a voluntary union is both entered into and left".
He was speaking to The Irish News ahead of tomorrow's Supreme Court ruling on whether Holyrood has the power to hold a second Scottish independence referendum.
The SNP-lead Scottish government believes a referendum falls within devolved powers, but the British government said it is a reserved matter.
The 2014 independence referendum which saw 55.3 support for the status quo was regarded as a once in a generation opportunity to change Scotland's constitutional status. However, Mr Russell, in common with his SNP colleagues, believes Brexit has created a "material change" that makes the case for a second referendum much more compelling.
"In 2016 we campaigned on a manifesto for the Scottish Parliament elections that said if Scotland was taken out of the EU against its will, then that would be a material change in circumstance – people accept that," he said.
"In 2017, we said by all means allow the Brexit negotiations to finish but then people have the right to choose whether they want an independent Scotland or whether they want to go on with a UK that has come out of the EU.
"This is particularly important issue for Scotland as it is in the north of Ireland too, but it's a particularly important issue for Scotland, because during the 2014 referendum campaign, a great deal was made of what was meant to be the impossibility of Scotland being in the EU, if it was independent – and the people who argued this, of course, are the very people who then took Scotland out of the EU against our will."
The SNP president stressed that he "doesn't think there's any exact correspondence" between the situations in Northern Ireland and Scotland but agrees that both would benefit from clarity around the circumstances that would bring about constitutional change.
"One of the things that we face is this question of how democratic mandates can be converted into into the chance for people to give their opinion about the future," he said.
Mr Russell said the vast majority of Holyrood politicians supported the right of the people of Scotland to determine how they're governed.
"That's a simple thing yet despite the fact that there are majorities in the Scottish Parliament for this for a long time, there is a resistance to essentially permitting that to happen," he said.
"The question is how in a democracy, we move from where we are, to where we need to be, which is for the public expression of their view."
The British government has consistently refused to clarify the circumstances under which a border poll will take place.
A statement yesterday from the Northern Ireland Office (NIO) said that in accordance with the Good FridayAgreement and the principle of consent, "Northern Ireland will remain part of the UK for as long as its people wish for it to be".
"There is no clear basis to suggest that a majority of people in Northern Ireland presently wish to separate from the United Kingdom," the NIO said.
Mr Russell said in any voluntary union "you have to know how that union can be altered or changed".
"I suppose the parallel I often use is with Article 50 of the Lisbon Treaty, as suppose the EU had said to the UK that it could not vote on whether or not they were in the EU?"
"Up until Article 50 – until the Lisbon Treaty itself – there was some confusion as to whether you could leave the EU, but what Article 50 did was codify the circumstances and the means by which that takes place and that's an entirely reasonable thing."
