THE Government says it is intolerable that a court in another jurisdiction has the power to over-ride the domestic parliament in part of the UK.

“How dare they tell us what we can and cannot do with our own laws?" No, not Lord Frost complaining about the European Court of Justice in Northern Ireland. That was the Scottish Government's furious reaction when the UK Supreme Court struck down Holyrood legislation on child welfare child welfare last week. There are some very obvious parallels.

Brussels insists that the European Court of Justice's rule in Northern Ireland must remain untrammelled, just like Westminster's rule in Scotland, because the province is part of the European Single Market. Britain says there can be no impediments to trade imposed by a foreign court because Northern Ireland is part of the United Kingdom. There is no legal way of reconciling these two contradictory principles. And the Good Friday Agreement is no help, since it assumed both the UK and Ireland were going to remain in the EU.

Read more: The Good Friday Agreement will be the first casualty of the Northern Ireland trade war

Opposition parties say that it's Boris Johnson's fault for signing the protocol in the first place. He just has to accept the consequences. But actually, he doesn't and he won't. Brexit has become the new legal reality and if the EU reacts with a trade war he will try to turn this into a Churchillian battle for parliamentary sovereignty against the “bully Brussels”. It might be politically convenient to blame Europe for empty shelves this Christmas, even though Britain's supply chain difficulties are a much wider problem.

Unionists in Northern Ireland are adamant that the border with the UK must be removed and claim that the Good Friday Agreement, and more importantly Article 6 of the Acts of Union, state respectively that there should be no change in the constitutional status of the North nor impediments to trade. The peace of the province is in the balance. The men of violence are waiting in the wings, hopeful that they might be able to wade into this legal conundrum with their Armalites.

Scottish devolution involved similar anomalies to the Northern Ireland Protocol. Holyrood was given legislative power over domestic affairs in Scotland. Real power to make laws. But at the same time, the UK Parliament retained legal supremacy. The fudge in the 1998 Scotland Act was that Holyrood exercised is powers on licence from the UK Parliament, which was still "sovereign in all matters”.

The UK Supreme Court struck down Holyrood's recent child protection laws, even though the UK Government supports them in principle, because they might have prevented Westminster legislating in this area. This was really a re-statement of the 2017 ruling on the Miller Case. Then, the UK Supreme Court ruled that the Sewel Convention, under which Westminster is not supposed to legislate in devolved areas, was just a “convention” – legal speak for a load of b****cks. Holyrood is being very firmly put in its place.

Read more: Why Tory Brexit spells Anarchy for the UK

Now shift focus to the Northern Ireland Protocol, rightly or wrongly signed by Mr Johnson in January. What the UK Government is now saying, in effect, is that like the Sewel Convention, the Protocol was just a form of words which did not alter the fundamental sovereign relationship between Great Britain and Northern Ireland. Leaving the Court of Justice of the EU with authority over part of the UK – Northern Ireland – is therefore illegal.

It is specifically unacceptable for the EU to apply checks to trade movements between the UK and the province, yet it has in chilled meats, in medicines and other products. A supermarket lorry now has to complete 700 pages of checks, according to the boss of Marks & Spencer, Archie Norman. The UK Government claims that 20% of all border checks in the EU now take place at this border within the UK.

This was always unsustainable and tomorrow Brussels is offering regulatory concessions on freedom of movement for sausages. However, the Brexit Minister, Lord Frost, has upped the ante by drawing a big red line under the Court of Justice. It must be replaced, he says by an independent arbitration panel to restore the principle of parliamentary sovereignty. There cannot be a de facto border in the Irish Sea.

Brussels understandably says that Britain accepted a diminution of sovereignty when it agreed to the North remaining in the European Single Market. What did they expect? The European Court of Justice polices the rules of that market – on matters like gene-editing of crops. Since there is to be no border on the mainland of Ireland then the checks would have to take place in the North – even though the Protocol recognised that the province remained part of the UK.

When he signed up to the Protocol, Mr Johnson presumably hoped Brussels would eventually relax its rules, allow free movement of goods into Northern Ireland and only check goods going thence to Ireland. But that would effectively shift the de facto border to the Irish mainland, which is why the Irish Government is now crying foul. If gene-edited crops could move seamlessly into the North, how could they not move seamlessly into the Republic absent a border?


A protest against the so-called Irish Sea border

A protest against the so-called Irish Sea border


And so it goes on. Rather like Schleswig-Holstein, there is no legal answer to this question, only a political one. The anomaly arose because of another constitutional innovation of devolution: the Good Friday Agreement of 1998, which ended the Troubles by merging the economies of North and South. It does not actually say there should be no trade border between the North and the Republic. It didn't think it was necessary, since both the UK and the Republic were both in the borderless EU single market. As in Scotland in 2014, no one in their right minds thought that the UK would leave the European Union.

Then came Brexit, and we are where we are. Brussels may have hoped that the Brits would eventually accept the rules of the single market for an easy life. But that isn't going to happen. In the past, such disputes were resolved by force of arms. Nowadays, we rely on jaw-jaw. But it's going to be a long one.

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