WE are now witnessing a significant constitutional contest between Holyrood and Westminster.

The immediate genesis is the decision by the Scottish Secretary Alister Jack to block a Bill, carried overwhelmingly by the Scottish Parliament, to reform the law on changing gender.

To be quite clear, I fully appreciate the scope and scale of the argument. Holyrood says it is entitled, under devolution, to act. Westminster says there is a clash with UK equalities law.

Further, this dispute has real substance. Some women’s groups remain anxious. Trans people feel they are facing further isolation and obloquy.

However, let us also ask a political question. Is this THE defining moment in Scotland’s prolonged constitutional discourse?

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Will Westminster obstruction mean that independence is now inevitable? The short answer is no. This is an important dispute, but not necessarily critical.

Consider the principal combatants, Nicola Sturgeon and Alister Jack.

It has been said by some Conservatives that the First Minister is explicitly using trans people to manufacture a conflict with Westminster.

Piffle. This would not by any stretch of the imagination be Nicola Sturgeon’s chosen battleground, were she seeking to pick a fight.

Remember there have been six long years of consultation. The FM has faced virulent, sustained attack from individuals and organisations who say they are standing up for women’s rights, which they fear might be eroded by the proposed changes.

Claims which the FM adamantly disputes, saying it is not about enhanced trans entitlement, but a more tolerant process. This has been highly emotive.

If anything, Nicola Sturgeon would have hoped that the passage of the Bill would have been followed by a period of relative silence. A period of peace, uneasy or otherwise.

HeraldScotland: Alister JackAlister Jack (Image: free)

She defends the reforms themselves. But now she is obliged to go further. She discerns a challenge to the legitimacy of Holyrood’s status – and thus, ultimately, to Scottish self-government, the very core of her political being.

And so she fights. She links the immediate dispute to independence, accusing the UK Government of treating Holyrood as a subordinate body and Mr Jack of acting “like a Governor General”.

The Bill was carried at Holyrood by 86 to 39, with nine SNP members opposed while Tories mostly voted against. There was limited Labour disquiet. Greens and LibDems backed reform.

In short, a clear decision, but a complex one.

By no means a contrived SNP device to provoke Westminster. If anything, it has caused political problems for Ms Sturgeon. Problems she had hoped would subside.

Turn to Alister Jack. Consider his demeanour when announcing the veto. His body language, the timbre of his voice.

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He seemed to me to be rather unhappy and uncertain. He refused, repeatedly, even when challenged by respected Parliamentarians, to defend his decision with detailed explanations, advising his inquisitors to consult the accompanying legal document, which only emerged later.

It was not an ebullient performance. The “Governor General”, if so he is to be billed, presented as a decidedly reluctant despot.

Why? I suspect he felt himself boxed in by legal advice – and by the broader aim of some Westminster Tories to pick a fight with Holyrood, to constrain devolved power.

To be clear, I believe Mr Jack shares the Conservative desire to limit Holyrood, or rather to underline the sovereignty of the Union parliament.

However, he does not perhaps have the zeal of other colleagues in this particular dispute. Liam Fox, for example, suggested to him that he should emphasise that the UK was “a unitary state”.

Mr Jack seemed happier with the suggestion that the heat be turned down upon this conflict, in search of a solution. That came from Iain Stewart, until very recently a Minister at the Scotland Office.

All the while, Michael Gove, the Levelling Up Secretary, sat sagaciously on the front bench, listening intently to Mr Jack’s statement.

There is quite evidently a broader strategy under way here, with Mr Gove at the core. He it was who devised the concept of placing a Union badge upon schemes of benefit to Scotland, rather than leaving such matters to the devolved Parliament.

Just this week, to the fury of Holyrood Ministers, Mr Gove announced £177m funding for 10 Scottish projects which would customarily be funded via devolved finance.

UK Ministers say that the concept of levelling up is designed to benefit the entirety of the UK – and that they are responding positively to bids from Scotland as well as elsewhere in these islands.

Labour has its own plan, devised by Gordon Brown. The idea is to disperse economic and political power across the UK as part of a full-scale reform of the constitution, topped off by replacing the House of Lords with an elected chamber, representing the nations and regions.

The purpose of these endeavours is, at least in part, to counter the pressure for independence. To anchor devolution within the Union state.

But back to Alister Jack. He says that the gender reform legislation can be rescued but only if it is amended by Holyrood to avoid any clash with UK equalities law. He declines to say how – and has now turned down an invitation to appear before a Holyrood committee.

The legal paper helps a little. It warns of two parallel and very different regimes operating in the UK. To which one might say “welcome to devolution” or recall that, historically, one could get married at a younger age in Scotland.

There is more. The paper says that the Equalities Act 2010, covering the whole UK, was predicated on the premise that it would always be relatively difficult to change gender. The Scottish Bill, apparently, “alters that careful balance.”

There we have it. The exercise of devolved legislative power upsets the unitary state.

Is there, however, some substance there, beyond the rhetoric? Holyrood Ministers say Westminster had ample opportunity to raise concerns during the passage of the legislation.

Which leaves us with a stand-off. Holyrood will not easily budge, believing that a wider campaign to belittle devolution is under way.

The more fervent Unionists say the fault lies with vaulting ambition at Holyrood.

Scotland’s trans people look on at the supposedly mighty – and despair.