THE Scottish Government could turn to the international courts to try to secure a vote on independence after a “de facto” referendum, according to a legal expert.

Dr Nick McKerrell, senior law lecturer at Glasgow Caledonian University, said it was another legal route which could be explored if the Supreme Court rejects the case for Holyrood to legislate for indyref2 – but he cautioned it would be “complicated”.

The SNP have applied to “intervene” in the Supreme Court case, which will be heard in October, with their argument focusing on the “inalienable right of all nations to self-determination which is enshrined in the United Nations charter”.

McKerrell said that using the International Court Of Justice – the main judicial body of the UN – could be a “longer-term” prospect.

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If the Supreme Court rules the Scottish Parliament does not have the power to hold a referendum, Nicola Sturgeon has said the next step will be to fight the next General Election on the issue of whether Scotland should be independent.

“The SNP politically says the next General Election will be a referendum,” McKerrell said.

“There are lots of things that could go wrong, but what that allows for is you have then got another potential legal route – although it much more complicated as it has never been done before – which is the international law.

“For example, say [the referendum] is blocked by the Supreme Court, the SNP win a majority in the next General Election, with 55% of the vote or whatever for independence parties, then they could say well, what can we do?

“The courts won’t allow us to have a referendum – we want the right of self-determination – that is when you go into a different level of legal discussion.

“But you need to go through the [Supreme Court] one first, the domestic one.”

Yes supporters will be hoping for a victory in the Supreme CourtDr Nick McKerrell

McKerrell said the International Court Of Justice has considered cases such as the declaration of independence by Kosovo, for example.

But he said: “It would be difficult to do. For example, you need to be a state recognised by the International Court Of Justice, so Scotland would have to do something to try to say we are a state to get action.

“That is when you have things like Catalonian referendum, then the declaration of independence or the Kosovan declaration of independence.

“That is a complicated route, which is why I don’t think they have even raised it as an issue as it is just too complicated to deal with now.”

He said he expected the Scottish Government would instead be hoping that winning a “de facto” referendum would put enough pressure on the UK Government to agree to indyref2.

“So whatever happens in the next election – if there is a hung Parliament or whatever if it is, you have got this result in Scotland that would be enough to concede that there would be a referendum,” he added.

Both the Scottish Government’s Lord Advocate Dorothy Bain QC and the UK Government’s Advocate General for Scotland Lord Stewart have now published their submissions to the Supreme Court.

The case will focus on two points – one “procedural” issue on whether it is appropriate to even refer the Referendum Bill to the Supreme Court at this point when it has not yet been passed by the Scottish Parliament.

The other aspect of the argument will look at the “substantive” issue of whether it is within Holyrood’s powers to hold indyref2.

Scotland’s Lord Advocate brought the case under paragraph 34 of Schedule 6 of the Scotland Act, which allows for law officers to make direct references to the Supreme Court on devolution issues in various circumstances.

Aileen McHarg, professor of public law and human rights at Durham University, said the case in October would be the “fullest consideration” yet of this “under-used” procedure.

“This is the first time it has ever been used in Scotland – there have been two cases from Northern Ireland which were both rejected but for very different factual circumstances,” she said.

“It is quite difficult to anticipate how the court would deal with it – what they have done is say we are going to decide both the competence of the procedure and the substantive issue at the same time.

“There is a number of different ways that could go. They could decide the reference is within competence and then go on to decide the substantive issue.

“They could decide the reference is not within competence and therefore say we are not going to decide the substantive issue.

“Or they could decide the reference is not competent, but still give their conclusion on the substantive issue.

“My sense is that having gone to the trouble of hearing arguments on the substance, that they will decide that substantive issue irrespective of how they decide on the competence of the reference, but I can’t be certain about that.”

Yes supporters will be hoping for a victory in the Supreme CourtAileen McHarg

McHarg said the Lord Advocate has presented the case for the Referendum Bill being within the powers of Holyrood “in its best light”.

“On balance, I would expect the Supreme Court to find it is outwith competence – however, there is genuine room for doubt here, there is a genuine issue to be resolved,” she said.

“One thing the Advocate General tries to argue is the legal outcome is self-evident – so they say one of the reasons for saying the reference should be rejected is that this isn’t a complicated issue, it is really self-evident, and the Lord Advocate should be able to advise the Scottish Government without having to go to court. It is not surprising that the UK Government takes that line, they have always taken that line going back to 2012 that a referendum bill would be outwith competence.

“Why do they do that? Because it leaves control in their court – it gives them control of the timing and terms of a referendum.”