One of the most destructive elements of Brexit has been its uncanny knack of underscoring the ill-feeling between the governments in London and Edinburgh. In keeping with its constituents’ wishes, Nicola Sturgeon’s Scottish government now looks set to frustrate the UK’s departure from the European Union (EU) at every turn.

Nigel Farage has often suggested that it would be illogical for Scotland to vote to become an independent country under Sturgeon’s leadership because a Scottish National Party (SNP) government would simply choose to pool Scottish sovereignty with Brussels instead of Westminster by re-joining the EU. Regardless of whether Farage’s point holds water, it might be more pertinent to turn his insight on its head: it was illogical, downright delusional in fact, to say Westminster would be totally sovereign over British laws after Brexit, because Parliament still governs the country alongside the regional assemblies in Edinburgh, Cardiff and Belfast.

Co-governance with the regional assemblies has been shown to be discordant ample times since ‘Brexit Day’ in January. The differing rules on the coronavirus lockdowns in the four nations of the UK have been immensely confusing, frequently smacking of plain political one-upmanship rather than proper scientific enquiry. On Brexit, it looks as if Sturgeon might disregard the government’s Internal Markets Bill and pass her own trade legislation, calling Johnson’s bill “a full-frontal assault on devolution”.

I’m not a constitutional expert, so I can’t say with certainty whether Sturgeon is right about that. But if the bill does in fact not represent overreach from Westminster, then part of the reason that Sturgeon can assert something which isn’t true is the fact that many of the terms of the relationship between Westminster and the devolved assemblies are poorly defined, arbitrary and hopelessly vulnerable to the transient whims of public opinion. Whilst most members of the commentariat have been focusing on making our relationship with the Europeans as stable and fruitful as possible, major instabilities within the British constitution have been overlooked.

The three devolved Parliaments are not like American state governments, the rights and jurisdictions of which are clearly laid out in the Constitution. If a state believes the Federal Government has overstepped the mark, the Supreme Court refers to the Constitution to assess whether overreach has occurred. All states have the same powers, and state governments are just as inherent a part of the US governance as the Federal government in Washington.

The Parliaments in Scotland, Wales and Northern Ireland, by contrast, were all created at different times, and all have slightly different powers. The devolved Parliaments can have their powers altered by the British government as long as the sitting Prime Minister desires it, and has a parliamentary majority to help him. After the Scottish independence referendum, David Cameron promised the Scots “devo-max”, as a way of responding to the close nature of the result. As a gesture of goodwill, he simultaneously enhanced the powers of the Welsh Assembly, but not to the same degree as the Scottish Parliament. However, he offered no explanation for why the Assembly in Cardiff would remain less powerful, or why he had interpreted nationalist fervour in Scotland as a clear sign that the Welsh were on the brink of drifting somewhere into the Irish Sea.

The relationship between the three Parliaments and its mothership in London resembles a rickety old building, the roof of which boasts a series of asymmetric and poorly built extensions. If a constitutional revolution did happen in Britain after 1945, it was devolution, not joining the EU. Random and arbitrary devolution has inhibited Westminster from governing the entire country far more than the European Commission ever did.

Of course, dysfunctionality doesn’t make the Scottish Parliament unconstitutional; the British Constitution is malleable and unwritten, which makes it much easier to change than the US Constitution. Ted Heath’s Tory government pooled our sovereignty with the Europeans in 1972 with a simple act of Parliament, thereby changing the British Constitution overnight. But just because something is constitutional doesn’t mean it works well. It doesn’t make it a good idea. The Internal Market Bill won’t be the last time that there are impasses in the years ahead, because the mandates of the Parliaments’ clash and their powers are far too easy to change. I’ve focused on Scotland here, but the potential for disaster in Northern Ireland is just as obvious.

Where does the Prime Minister enter into the picture in all of this? He’s certainly having a torrid time dealing with Scotland at present. One year into his premiership, it’s obvious that he has few guiding principles. In truth, you didn’t need a year to see this. Whether Johnson’s love for the expedient would extend to advocating independence for Scotland is unlikely. But, privately at least, he must have clocked that not having to listen to those loudmouths over Hadrian’s Wall would definitely make his life easier.

If you don’t like the job he’s doing (I count myself among you, by the way), then you might conclude you don’t mind that a by-product of our constitutional disorder is Johnson’s failure to deliver on his manifesto. What is worrying though, is that far from enhancing democracy in our country, devolution is compounding an incipient feeling that Britain is now ungovernable. I don’t blame Sturgeon for this; there is nothing wrong with scrutinising the government and its legislation, but there is an ocean of difference between careful scrutiny and institutional collapse. The former, essential to any democracy, was traditionally the responsibility of the opposition parties, the House of Lords, and an independent judiciary. The country was governed reasonably well with just one government. Creating three regional Parliaments on a whim and handing them new powers arbitrarily has simply led to a pile-up of different mandates, rather than improving accountability. If many different governments squabble over the right to govern, none of them will govern. In handing back power to our domestic governments, Brexit seems poised to unleash a crisis of democratic legitimacy far greater in severity than even itself.