The UK Supreme Court’s Brexit Decision: Probably Right and Yet So Unnecessary

The UK’s Supreme Court has ruled that Parliament must agree to make Britain’s exit from the European Union, which the British people voted for last June, a reality. Her Majesty’s Government (HMG) had argued that following the vote, all that was needed was for Ministers to exercise the Royal Prerogative of treaty-making powers to withdraw from the EU treaties. The Supreme Court disagreed, saying that Parliament had constrained that power, perhaps unintentionally, in 1972 when the European Communities Act was passed. The judgment can be read two ways – as an insult to democracy, or as a rightful reiteration of Parliamentary sovereignty. In reality, it is both.

To begin with, we must recognize that British statute law recognizes no legislative power other than Parliament, or, to be more precise, Queen-in-Parliament. There is no “We the People” preamble to Britain’s unwritten constitution. Despite the fact that the people quite happily chopped off one King’s head and drove another into exile in the 17th Century, it was Parliament that was the vehicle of change, and it is Parliament that is the rock on which democracy is founded there.

This means that the question that the Court decided today was not one of popular will, precisely because it couldn’t be, as a matter of law. Had the referendum act of 2015 said that the Government would take certain actions following the referendum, as previous referenda acts had done, that would have been dispositive of the case, and the Supreme Court would probably not have needed to get involved. It didn’t, however.

Instead, the case revolved around the principle of “dualism.” This principle, which the Court admitted was fundamental to the British constitution, says that the executive power (technically HM the Queen, in reality the Prime Minister and her government) has power over international law and treaties, while Parliament has power over domestic law. It is similar to the separation of powers explicit in the US Constitution. This is the principle HMG relied on when it suggested it had the power to withdraw from the EU as an exercise of the treaty-making power.

By contrast, the original plaintiffs in the case argued that Parliament had granted them rights through the 1972 Act that had become part of domestic law, and therefore Parliament, not Ministers, had to act to remove those rights. Lord Hughes’s dissent clearly explains the problem.

The Court decided that the 1972 Act restrained the treaty-making power as it made the EU institutions a source of domestic law, giving jurisdiction to Parliament. What the Court comes very close to saying, yet does not, is that the 1972 Act was therefore a constitutional abomination, not just ceding legislative power to alien bodies but constraining the executive in a way that had not been done before.

Paragraph 68 of the judgment underlines how utterly alien the 1972 act was to fundamental constitutional principles, and yet it was passed in accordance with those principles. It says, “Rules which would…normally be incompatible with UK constitutional principles became part of our constitutional arrangements as a result of the 1972 Act and the 1972 Accession Treaty for as long as the 1972 Act remains in place.”

So be it. While Lord Reed’s dissent taking the side of HMG and the Royal Prerogative is persuasive, it seems clear to me that the only way the UK can get out of the mess it placed itself in back in 1972 is to kill the 1972 Act as “a matter of constitutional hygiene,” as Michael Greve said of Obamacare.

The saving grace is that the Court handed HMG two victories in this defeat. First, they found that the devolved assemblies of Scotland, Wales, and Northern Ireland have no say in the UK’s Parliament’s decision (they too are creations of Parliament), which removes a potential stumbling block. Secondly, the Court admitted that the repeal of the 1972 Act could be very brief, yet nevertheless have the constitutional import needed. Given that even Labour Party leader Jeremy Corbyn recognizes that to oppose such a bill would be an act of spectacular political suicide*, the Court has in reality given Mrs. May a very small hurdle to jump over.

So Parliamentary primacy over the Executive has been asserted in this one very specific case of the 1972 Act (and its successors). The decision can be viewed as conservative – Diceyan in its view of the constitution, even.

However, I said earlier that the decision was an insult to democracy. It is. Lord Carnwath’s dissent is the only place I can see that gets to the heart of the matter – that Ministers using the Royal Prerogative would not be an “untrammeled” exercise of executive power. It would be in response to the expressed will of a majority of the British people who expressed an opinion.

In other words, it would be the very opposite of an arbitrary use of power. And it is to stop arbitrary abuses of power for which we have the Parliamentary system in the first place. As the great economist Douglass North and Barry Weingast of the Hoover Institution noted in 1989, the Queen-in-Parliament system was put in place to prevent arbitrary actions of the executive, specifically those affecting property rights, against the common people. It succeeded splendidly at that.

To use the argument that Parliament must authorize executive power to stop a decision on the basis it could be arbitrary when that decision is quite clearly the settled decision of the people may be an exercise in formalism that weakens rather than protects the rule of law (see the response of the popular press to the lower court’s decision). Particularly when, as Lord Reed argues, there is a perfectly good constitutional principle that would exempt Ministers from Parliamentary approval. As I said here just before the Brexit vote, “a vote to Remain would represent an end to Britain’s 800 year experiment in restraining the executive through consent, natural right, and popular will.” Ministers exercising the Royal Prerogative following the vote would be consistent with that experiment, not contradictory to it, as the Court implicitly seems to believe.

To put it mildly, the British constitution is currently confused as to its purpose, and a lot of the blame for that can be laid at the foot of the 1972 Act and the pernicious influence of a set of alien institutions and principles. The sooner it is gone, dismembered, with a stake through its heart, the better.

Originally posted to National Review.