Scottish secretary Alister Jack is preparing to launch a legal challenge against legislation welcomed by campaigners

Leading legislation that has been praised by children’s charities could be under threat from a UK government challenge.

Scotland became one of the first nations in the world to embrace human rights for children in its domestic law system earlier this month when MSPs voted unanimously for the United Nations Convention on the Rights of the Child (Incorporation) (Scotland) Bill to become law. The legislation means public authorities will have to comply with children’s rights.

The move was welcomed by campaigners for children's rights, however the legislation could be under threat due to a challenge from the UK government.

Scottish secretary Alister Jack has raised concerns that it encroaches on areas outwith the Scottish Parliament’s competency in a letter sent to Deputy First Minister John Swinney.

Westminster has taken issue with some sections from the bill and Jack warned that law officers were considering involving the Supreme Court after Swinney rejected requests to amend the bill, which was passed unanimously on 16 March.

He said: “Protecting vulnerable children and protecting children’s rights is a priority for the UK government, and I know that we share these common objectives. We ratified the United Nations Convention on the Rights of the Child almost 30 years ago, in 1991, and have continued to promote and uphold children’s rights. We have also ratified the optional Protocol to the Convention on the Rights of the Child on the involvement of children in armed conflict and the optional Protocol to the Convention on the Rights of the Child on the sale of children child prostitution and child pornography.

“We welcome the Scottish Government’s support for children’s rights and respect the Scottish Parliament’s right to legislate in this area. Unfortunately, the legislative competence of specific provisions in the UNCRC Bill is in doubt.

“The UK government has concerns with section six of the bill relating to the legal obligations it could be seen to place on UK government ministers in reserved areas.

“This in turn means that the effect of the legislation may not be clear to citizens, stakeholders and those who may seek to use the legislation to test that relevant authorities are meeting their duties.”

If law officers decide to send the bill to the Supreme Court then it will not receive royal assent or pass into law until after the UK’s top judges have considered it. They could decide to either allow the bill to pass, or return it to MSPs to be altered.

The bill was welcomed by Children and Young People’s Commissioner for Scotland Bruce Adamson, Together (Scottish Alliance for Children’s Rights) and members of the Scottish Youth Parliament when it was supported by MSPs last week.

A Scottish Government spokesperson said: “All parts of the UNCRC Bill are within the legislative competence of the Scottish Parliament.

"The changes proposed by the UK government  would significantly undermine the protection for children’s rights in Scotland that the bill seeks to put in place, threatening to undercut both the important measures contained in the legislation and key principles of devolution.

“These changes would mean that crucial provisions in the bill would not apply to major pieces of legislation that fall within the legislative competence of the Scottish Parliament and which are key in relation to children’s rights. This would include the Children (Scotland) Act 1995, the Education (Scotland) Act 1996 and the Children and Young Persons (Scotland) Act 1937.”