A COURTROOM showdown over the blocking of Holyrood’s gender reform legislation will take place this week – but the legal battle could last until the end of next year, it has been predicted.

The Scottish Government has launched a legal challenge over UK ministers using veto powers – known as a Section 35 order – to block the Gender Recognition Reform (­Scotland) Bill which was passed by MSPs in December.

The case will be heard by Judge Lady Haldane at the Court of Session in Edinburgh over three days this week, beginning on Tuesday.

Whatever the outcome – which won’t be known for around six weeks – legal experts predict the losing side is expected to appeal given the ­political significance of the case.

This would mean a further ­hearing at the Inner House of the Court of Session, and it could then end up in the highest court in the land, the ­Supreme Court – likely stretching the legal battle to the end of 2024.

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Dr Nick McKerrell, senior law ­lecturer at Glasgow ­Caledonian ­University, said the Scottish ­Government had a “fairly strong” case to challenge UK ministers on the use of the Section 35.

He said he expected both sides would launch an appeal – although Scottish ministers were likely to face rhetoric about the case being a “waste of money”.

“This is a critical hearing which will be the first in a series of hearings on it,” he said. “You could argue the Section 35 probably should be looked at by the Supreme Court because it is such a significant power – it gives the power of veto to the UK Government and has never been used before.

“A Section 35 order to allow a law to be blocked without any ­discussion – that is a big thing in a devolved ­settlement.

“The problem with that in the ­current era, cost of living and so on, is that it costs money to go to court, which I think the Scottish ­Government in particular will get flack about that.”

“But it is important and requires legal oversight I would say.”

He added: “So I think both sides will appeal. There is no resolution this week anyway, as this week is just the arguments – it will be six weeks’ time, start of November you get an outcome.

“An appeal would be in the new year, appeal to Supreme Court at the end of next year – so it is the end of 2024 you would probably be talking.”

McKerrell emphasised that the ­judicial review would not be ­examining whether gender ­recognition reform was “a good or bad thing” but focus on the decision by Scottish Secretary Alister Jack to launch the Section 35 order.

He said the first argument the ­Scottish Government would make is that Jack acted outwith his powers or had used the power in an ­“irrational” way.

Under the Scotland Act, the ­Section 35 can be used if it is thought ­legislation passed by Holyrood will “modify” the law as it applies to ­reserved matters.

While gender recognition is ­devolved in Scotland, the issue of equal opportunities is reserved to Westminster.

McKerrell said: “The first ­argument the Scottish Government will make is that the Gender Recognition Reform Act does not modify UK law, so ­therefore the UK Government don’t have the power to do it. Because it is no ­modification.

“The Scottish Government will argue – and I think it is a relatively strong argument – that there is no clear alteration of UK equalities law.

“The UK Government will ­obviously argue it does modify the law, and they will outline where they think it is modifying the law, weakening single-sex spaces and so on.

“The issue there I think is that ­although they argue theoretically these things could happen, the ­wording of the law on Section 35 states modification – and modification for me is a strong word because it is saying the law is actually altered.

“In this case, for the Section 35 to be used there has to be evidence of modification. Those who have argued in favour of the Section 35 because they think it is modified, a lot of them are theoretical modifications.

“So the Scottish Government’s ­argument will have to start from that basis.”

McKerrell said even if the court accepted that gender recognition ­reform did modify the UK laws then the UK Government also has to have reasonable grounds to believe the changes would have an “adverse effect”.

The Scottish Government would then have to argue that there is no reason to think the law would have an adverse effect – which will result in more of a focus on the impact of the gender reform legislation.

But McKerrell said the UK Government will have to then give reasons and specific examples.

“The legalese which they have ­published in terms of arguing against, it basically amounts to same-sex ­spaces being undermined,” he said.

“That is where you will get more to the content of the gender recognition reform laws.”

But he added: “Judicial review is very specifically about [if] they have the power to do it – and the reasons underpinning their decision to do it.”