THE Supreme Court made “significant mistakes” in its ruling on indyref2, a legal expert has argued in a new paper which sets out the international legal routes to independence.

Alba MP Neale Hanvey has published a legal opinion by Professor Robert McCorquodale, of Brick Court Chambers and a member of the United Nations’ working group on business and human rights.

The paper, launched at a press conference in Westminster on Tuesday, forms what Alba say is the first detailed criticism of the Supreme Court’s ruling last year which blocked the Scottish Government from holding a second independence referendum.

In it, Prof. McCorquodale argued the Supreme Court was “mistaken” in its readings of the arguments put forward by the SNP who argued in their submissions last year that Scotland’s right to self-determination ought to be considered.

The Supreme Court effectively tossed out the party’s arguments saying they were not relevant when Scots did not live in a colony and had access to political representation.

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Prof McCorquodale took issue with the court’s interpretation of the case of the attempted secession of Quebec from Canada, saying it was wrong to consider the case as being “directly applicable” to the situation in the UK.

The SNP had referred the court to consider the case of Quebec’s non-legally binding referendum on secession as a means of “ascertaining the views of the electorate on important political questions”.

The court ruled that because any vote would have political implications, this did not apply in the Scottish case – something Alba have now argued, in light of Prof. McCorquodale’s opinion, strengthens arguments for using elections rather than referendums as a means of securing independence.

The paper went on to argue that the court’s reading of a statement – also submitted by the SNP – in which the UK Government argued, referring to Kosovo’s recent unilateral declaration of independence from Serbia that states did not have a right to prohibit secession.

In the report’s conclusions, Prof. McCorquodale argued that there were international legal routes through which Scotland could secure independence – but said they were very limited.

The report outlined two routes, one in which Scotland would need to obtain an “advisory opinion” from the International Court of Justice (ICJ).

But McCorquodale warned: “This requires a majority vote by states in the UN General Assembly to refer a legal question to the ICJ, and for the ICJ to determine the matter.

“It also requires a state to take this forward on behalf of the people of Scotland, which may prove difficult.”

He went on to argue that Scotland could make a unilateral declaration of independence – but said this would only be legitimate if there was a clear majority in favour of Scotland leaving the UK.

“This requires a clear majority of people representing Scotland to indicate their approval but it should not be done by the Scottish Parliament, as the latter is within UK domestic law,” he wrote.

“This could be done, for example, through a convention of elected and diverse representatives from across Scotland with a clear majority in favour.

“This approach relies for its effectiveness on the recognition by states of the statehood of Scotland.”

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Prof. McCorquodale concluded: “There are no easy routes to find a remedy in international law for the people of Scotland to exercise their right to self-determination by secession and so seek their independence from the UK.

“However, as seen in the history of other peoples with the right to self-determination seeking to become states, while this is challenging, it is by no means impossible.”

Presenting the opinion in London on Tuesday, Hanvey said the Alba Party had no plans yet to present the findings to the Scottish Government.

He said: “Because the Scottish Government is effectively an organ of the UK state – and that is why it’s constrained, the reservation of powers is part of the UK arrangement, it’s not a reflection on the Scottish Parliament – but because it’s a part of that apparatus there is a need to look at this through a slightly different prism, if you like.

“So that’s part of the UK state but the people of Scotland, our rights to self-determination are not bound to an organ of the UK state. Therefore, the movement – and it’s a point I’ve been making many times – the movement are absolutely central players in how we take the case for independence forward.”

He added: “The legal opinion we are publishing today reinforces and supports equitable access to the right to self-determination of all peoples within the current Union. They also offer robust challenge to the legally flawed judgement of the UK Supreme Court.”