THE new Lord Advocate is to miss the first big constitutional case being heard by the UK Supreme Court since her appointment.

Dorothy Bain QC will not participate in the high-profile clash between London and Edinburgh over Holyrood’s powers next week. 

Her predecessor, James Wolffe QC, represented the Scottish Government in person in several constitutional cases at the Supreme Court, including the only parallel case.

Instead of Ms Bain, who was sworn in as Nicola Sturgeon’s top legal adviser on Tuesday, the Scottish Government will be represented by another QC, James Mure, who has represented the Lord Advocate’s offce in other cases.

The UK law officers, who brought the case, will also delegate their role to other counsel.

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The virtual hearings on Monday and Tuesday are a result of the UK Government’s law officers challenging two recent bills passed by the Scottish Parliament. 

The Bills both incorporate outside standards into Scots law - the United Nations Convention on the Rights of the Child (UNCRC) and European Charter of Local Self-Government.

The UNCRC Bill is intended to give enhanced legal protection to children by obliging public authorities to respect their rights and comply with UNCRC requirements.

Both Bills were passed unanimously by MSPs in March but have not received royal assent and cannot yet become law because of the referral to the Supreme Court.

The UK Government argues they encroach on Westminster’s sovereign powers.

The Supreme Court could uphold the Bills as competent or send them back to Holyrood for amending.

SNP ministers have called the referral a “blatant power grab” by Westminster.

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Ms Sturgeon also cited the legal action during the Holyrood election campaign as an example of Westminster over-reach, while SNP Westminster leader Ian Blackford raised it at PMQs, accusing Boris Johnson of “shamefully” taking the Scottish Parliament to court.

That earned Mr Blackford a rebuke from the Dean of the Faculty of Advocates Roddy Dunlop QC, who said: “It’s a constitutional question, not a political one.”

Asked in response if she was weaponising the issue to whip up support for independence, Ms Sturgeon said: “The Dean of the Faculty of Advocates is entitled to his opinion. Everybody’s entitled to his opinion. It doesn’t necessarily mean he is right and my opinion on this is wrong. It’s a Bill within devolved competence."

Until now, only one other Holyrood Bill has been referred to the Supreme Court.  

This was in 2018 when Holyrood passed a Bill about the continuity of EU laws after Brexit.

Mr Wolffe, as Lord Advocate, appeared at the Supreme Court for the Scottish Government.

He also appeared in 2019 as an intervener in the case which saw the Supreme Court rule Boris Johnson’s decision to prorogue the UK parliament over Brexit was unlawful.

Mr Wolffe also appeared in 2016 as an intervener in the famous case brought by Gina Miller which established that MPs, not ministers, had to trigger the Brexit withdrawal mechanism.

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Nominating Ms Bain for the position of Lord Advocate to parliament on June 17, Ms Sturgeon said her “extensive experience” included the Supreme Court.

Five justices, including Lord Reed, the Scottish judge who is President of the Supreme Court, will hear the related Holyrood cases via video conference next week.

The UK Government is due to present its case on Monday, with the Scottish Government responding from 10.30am to 1pm and from 2pm to 2.30pm on Tuesday.

The UK law officers challenged the Holyrood legislation as they were concerned “both Bills would bestow upon the Scottish courts extensive powers to interpret and scrutinise primary legislation passed by the sovereign UK Parliament”.

As that would modify Section 28(7) of the Scotland Act 1998, the UK law officers consider parts of the Bills are therefore “outside the legislative competence of the Scottish Parliament”.

The UK law officers are also seeking the court’s guidance on the correct reading of the Bills to ensure they are within Holyrood’s legislative competence, “if such a reading is possible”.

The UK law officers, Attorney General Michael Ellis and Advocate General for Scotland Lord Stewart of Dirleton, are being represented Sir James Eadie QC and David Johnston QC.

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A second respondent, the Counsel General for Wales Mick Antoniw, is being represnred by Helen Mountfield QC.

A Scottish Government spokesperson said: “It was the intention from the outset that James Mure QC represent the Lord Advocate in these proceedings.

“The Lord Advocate is the appropriate law officer in Scotland to be the responding party in respect of these two Bills, but it is not uncommon for Counsel to represent the Lord Advocate.”