Nicola Sturgeon has accused Boris Johnson’s government of a “morally repugnant” attempt to overrule the Scottish parliament after it emerged two bills passed by Holyrood have been referred to the Supreme Court.
The UK government has expressed concerns the bills contain provisions which are outside the Edinburgh parliament’s powers.
But with just weeks to go before crunch Holyrood elections, Scotland’s first minister described the move as "politically catastrophic... [and] morally repugnant" as well as “jaw-dropping”.
The SNP has said that overall victory in May’s elections would be a mandate for another independence referendum.
But Ms Sturgeon’s party is facing a surprise electoral challenge from its former leader Alex Salmond, and his new party Alba.
Attacking the UK government’s decision on Twitter, Sturgeon said: “Jaw-dropping. The UK Tory government is going to court to challenge a law passed by [Scottish parliament] unanimously.
“And for what? To protect their ability to legislate/act in ways that breach children’s rights in Scotland.“Politically catastrophic, but also morally repugnant.”
The bills, the United Nations Convention on the Rights of the Child (Incorporation) (Scotland) Bill and the European Charter of Local Self-Government (Incorporation) (Scotland) Bill, were passed in the weeks leading up to parliament’s closure for the elections.
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Before it passed, Scottish secretary Alister Jack wrote to request changes be made to the children’s bill.
There are also warnings that both bills contain technical aspects which may place legal duties on UK ministers.
A spokeswoman for the UK government said: "UK government law officers have today referred two bills from the Scottish parliament to the Supreme Court under Section 33 of the Scotland Act 1998.
"The UK government law officers’ concerns are not about the substance of the legislation, rather whether parts are outwith the legislative competence of the Scottish parliament."
Deputy first minister John Swinney promised his government would fight the challenge, if re-elected.
"Not a single voice in the parliament was raised against the bill. It passed unanimously," he said.
"And, crucially, it has been certified independently by the presiding officer [Holyrood’s equivalent of the House of Commons speaker] as being within the powers of the Scottish parliament.
"Now, the Tory Westminster government is trying to veto those rights. That is not just morally repugnant but it is also deeply menacing.
"The only people who need fear this bill are people who want to breach children’s rights.”
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