THE First Minister stressed Scotland’s Claim of Right in a speech marking 20 years of devolution.

Addressing a Law Society of Scotland conference in Edinburgh, Nicola Sturgeon said Brexit and the UK Government’s use of the Supreme Court had left the Union “in shreds”.

The speech addressed the progress that had been made through devolution – but she said Scotland now faced the biggest democratic deficit in its post-war history,

Sturgeon said: “One of the key milestones in progress towards a Scottish Parliament was the signing of the Claim of Right for Scotland in 1989.

“The signatories affirmed ‘the sovereign right of the Scottish people to determine the form of Government best suited to their needs’.

“In doing so the signatories articulated the key distinction between the UK and Scottish conceptions of sovereignty. In the Westminster system, power has traditionally been exercised by the Crown in Parliament; here, it rests with the people of Scotland.”

The Claim of Right was officially endorsed by the House of Commons last year.

The First Minister criticised the UK Government’s use of the Supreme Court in challenging Scotland’s Brexit Continuity Bill.

Judges found that at the time the Bill was passed, only one part of it had been outside of Holyrood’s legislative competence – but the UK amended the Scotland Act while the case was ongoing.

Sturgeon cited Lord Reed, deputy president of the Supreme Court, in saying it set a precedent for the UK to render Holyrood bills invalid in future.

Sturgeon said: “The fact that this is legally possible is in itself remarkable. But the fact that a UK Government has actually behaved in such a way is extraordinary.

“It leaves in shreds the supposed safeguards of constitutional convention – or proper behaviour, or indeed honourable conduct – which are supposed to take the place of law in our constitution.

“Indeed, it sometimes seems as though the existing frameworks for intergovernmental relations simply cannot bear the weight of Brexit.”

The First Minister said it must be for the Scottish people to decide their future, and again stressed the urgent need for Scotland’s independence.

She said: “We know that our closest relationships will always be with our friends and neighbours in the United Kingdom so that willingness to co-operate will continue regardless of our future constitutional status but that co-operation – if it is to be effective – must be on the basis of mutual agreement and consent.

“Obviously I have no objections to people who are against independence, everybody who is against independence is absolutely entitled to argue that, whether that is Theresa May or David Cameron or Jeremy Hunt or Boris Johnson.

“Where I take issue is the idea that it is for them – or indeed for me – to decide Scotland’s future, it should be for the Scottish people to decide our future.”

Sturgeon said she would oppose any calls for a threshold to be a requirement in any future independence referendum.

She said: “I don’t take the view that that should be a requirement – the narrowness of the Brexit result absolutely has been a factor in what’s come since but I don’t think what has happened since the Brexit vote has been in any way inevitable.

“I think a basic tenet of democracy – how we take decisions – is by a majority vote.

“I don’t think that the mess that Brexit has become was inevitable, even with the narrowness of the result.”

She accused Tories of seeking to “deepen division rather than bring people together” in the wake of the EU referendum.