THE SNP have published their application to intervene in the Lord Advocate’s reference of the Referendum Bill to the Supreme Court.

In a 15-page submission to the court, lawyers Claire Mitchell QC and David Welsh argue that it would “fair, just and reasonable” to allow the SNP to intervene in the case.

It comes after the Scottish Government's top legal representative, the Lord Advocate, submitted their written case, with the court due to hear arguments on October 11 and 12

The SNP's intervention argues that the Supreme Court has previously stated it would "be willing to give permission to bodies to intervene where the views of such bodies 'might be of assistance'".

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The SNP’s Kirsten Oswald said that the party’s application to intervene is intended to “support and complement” the arguments for the bill being within the Scottish Parliament’s competence.

It adds: “The applicant is a person with an interest in these proceedings, standing its history, involvement, and prominence in UK politics on the matter of Scottish independence and, in particular, the rights of the Scottish people to self-determination.”

The party argues that if they were allowed to intervene in the case this would mostly be by written submission, but also asked the court to allow “short oral submissions to supplement" that.

They also set out the numerous mandates won since the first referendum in 2014, as well as the period of “exceptional political turbulence” in the wake of the 2016 Brexit vote, and that the majority of Scots across all local authorities voted Remain.

The SNP added that due to their numerous manifesto commitments to hold indyref2 that they have a “duty” to deliver a referendum for the Scottish people.

They added: “The position of the applicant as regards Scottish independence could scarcely be clearer.

"As with the basis of the Salisbury Convention that the House of Lords does not generally prevent the UK Government of the day from seeking to implement its manifesto commitments, the applicant’s position is that it is at least constitutionally improper for any part of the UK Government to seek to prevent a devolved administration from implementing a clear manifesto commitment on which its demos [people] has elected it to govern.”

The document argues that the tradition of “parliamentary sovereignty” as a fundamental part of the UK Constitution is part of English law - not Scots law.

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It added: “The UK Parliament may well have supreme legislative competence, in that it can legislate in relation to anything, but it is not the case that, consistent with the rule of law, it is able to override, remove, or otherwise interfere with fundamental rights (such as the right to self-determination) without clear and unambiguous statutory authority and without a clear, rational and evidenced basis for doing so.”

The main argument from the SNP is that the referendum vote “does not of itself implement the result or the outcome of that referendum”.

They added: “The referendum indicates the view of the demos on the question posed to it. That there will be subsequent secondary discussions between the UK and Scottish Governments in the event that the Scottish people indicate their support for Scottish independence does not change that.

“Those discussions are separate from the referendum and do not inform its purpose.”

The National: The SNP's intervention would be separate to the Scottish Government's - led by the Lord AdvocateThe SNP's intervention would be separate to the Scottish Government's - led by the Lord Advocate (Image: Newsquest)

The document adds that whatever the referendum outcome Scotland wouldn't, and couldn’t as a matter of law, “become an independent country by default the day after ‘referendum day’. The referendum itself is not an act of secession; it is not a unilateral declaration of independence.”

For independence to take effect there would need to be a “process of negotiation and subsequent legislation”, it adds.

The party say they intend to make “discrete and complementary legal arguments” throughout the case and requested time to be allocated for the SNP's oral submissions to the court.

SNP business convener Oswald said: “The SNP’s application is now with the Supreme Court.

"It is intended to support and complement the arguments for the Bill being within the Scottish Parliament’s competence that are set out in the Lord Advocate’s written case.

“The SNP’s application focuses on the inalienable right of all nations to self-determination which is enshrined in the United Nations charter and argues that the Scotland Act should be interpreted in a way that upholds rather than denies that right.

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“The Bill raises a fundamental issue of democracy - in line with the principle of self-determination, Scotland’s future must be decided by those who live here, not dictated by Westminster politicians.

“It is now for the Supreme Court to determine whether our application to intervene should be granted.”

It comes as a Freedom of Information request to the Scottish Government revealed that they spent £27,193.84 on “external counsel advising on the referral to the Supreme Court”.