THE UK Government is undermining democracy and the law by its “unreasonable and immoral” ignoring of the SNP’s mandate for an independence referendum, according to a law professor.

Sionaidh Douglas-Scott, anniversary chair in law at Queen Mary University London, said the UK Government has acknowledged over many years that the Union is voluntary and that Scotland has a right to self-determination, which allows for "independence in principle".

Writing in a blog post for Edinburgh University's Centre for Constitutional Change, she said as this can only be lawfully achieved through negotiations with the UK Government, it “therefore follows that such negotiation should not be unreasonably withheld”.

She said the UK Government has undermined democracy and the “rule of law” by ignoring the SNP’s Holyrood election success in 2021 and the “mandate of a lawful government”.

And while the SNP have stressed they want to hold a legal referendum, she argued it also is important that the “UK Government’s conduct be exposed as not merely unreasonable and immoral, but also as contravening some key legal principles”.

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In the blog titled Scottish Independence And The UK Government’s Unreasonable Refusal To Negotiate, she sets out five legal arguments for holding a referendum which she says should be “asserted as clearly and loudly as possible”.

This includes that Scotland’s consent to the Union is ongoing and can be withdrawn, that Scotland has a right to self-determination in international law, and that the principle of democracy means the mandates of elected governments should be “taken seriously and not overridden”.

Another ground is there are many areas of law which allow a change of circumstance – as in the case of Brexit – to override previous consent given and there is also a requirement for the UK Government to act in “good faith”.

Douglas-Scott, who was previously professor of European and Human Rights law at the University of Oxford, said even if the Supreme Court rules that Holyrood does not have the power to hold a referendum it “does not end matters”.

“Scottish independence is far broader than the issue of competence to hold a referendum under the 1998 Scotland Act,” she said.

“The devolved settlement is barely 25 years old but Scotland and England have been joined since 1707 in a voluntary parliamentary union concluded between two sovereign States.

“Importantly, this relationship, and the consent of both parties to it, is ongoing, not all done and dusted three centuries ago, and, since 1707, Scotland has maintained its own separate legal system, Church, education system and cultural heritage.”

Douglas-Scott said the UK Government – including prime ministers – have acknowledged through its conduct over many years that Scotland has a right to self-determination.

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“However, although the Scottish people have an acknowledged right to self-determination, this can only be lawfully actualized through consensual negotiations with the UK Government,” she wrote.

“It therefore follows that such negotiation should not be unreasonably withheld.”

She went on: “Further, democracy is a key constitutional principle, and the UK Government has undermined democracy by ignoring the SNP’s 2021 manifesto pledge and its endorsement by the Scottish people, as well as the January 2020 Scottish Parliament vote for an independence referendum.

“By ignoring the mandate of a lawful government, the UK Government’s conduct in this context also undermines the rule of law.”

Douglas-Scott argued there is an obligation of the UK Government to permit an independence referendum – based on legal grounds of changes of circumstances and “good faith”.

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She concluded: “The UK Government may not refuse to do so unreasonably. It should not take decisions which violate Scotland’s fundamental right to self-determination, or democracy, without a clear, rational and evidenced basis for doing so (which has not been forthcoming).

“The SNP have always stressed the importance of legality – especially salient given that an independent Scotland would want recognition from the international community, not least if it wished to become an EU member.

“However, it is equally important that the UK Government’s conduct be exposed as not merely unreasonable and immoral, but also as contravening some key legal principles.”

SNP MSP Emma Harper said: "The Scottish Government has a cast-iron mandate to hold a referendum, as Professor Douglas-Scott has clearly outlined.

"The Tories are running scared of democracy in Scotland. Their position is completely out of touch with the people of Scotland - and it is not sustainable."

A spokesperson for the UK Government said: "People across Scotland want both their governments to be working together, focusing their attention and resources on the issues that matter to them, not talking about another independence referendum.

"That includes building economic stability, tackling the cost of living, ensuring our energy security and leading the international response against Russia’s invasion of Ukraine."