As MPs prepared for a second round of indicative voting on Brexit options, Richard Ekins and Stephen Laws argued in the Sunday Times that, if Parliament were to reach a legislative settlement on Brexit, the government should advise the queen to withhold her assent to the legislation. ‘The process of royal assent has become a formality, but if legislation would be otherwise passed by an abuse of constitutional process … the government might plausibly decide to advise Her Majesty not to assent to the Bill.’

Ekins is an associate professor at Oxford and the head of Policy Exchange’s Judicial Power Project; Laws is a former first parliamentary counsel and a senior fellow at Policy Exchange. They recognise that there may be something a little off-colour about what they are suggesting (‘royal assent has become a formality, but …’). The justification for the exceptional course of action they propose seems to lie in the great principle of tit-for-tat. It is cast as a sort of counterstrike to parliamentarians getting ideas above their station. Attempts by MPs to seize power from the government will ‘provoke damaging institutional conflict’ and ‘may prompt the government to respond with countermeasures’.

This solution is a bit like amputating an arm to cure a broken wrist. What kind of remedy for ‘institutional conflict’ relies on getting the queen politically involved in Brexit (surely thereby inflaming the conflict), while blithely trampling over one of our oldest and simplest constitutional rules? Public lawyers ought to be better at this stuff – and good, in particular, at not sacrificing long-term constitutional gains for short-term political wins.

The proposal is bad as a matter of constitutional politics. But what about its merits as constitutional law? A number of things appear to lend support to the Ekins and Laws proposal. In general, Westminster democracy works most often (and best) when the government draws up the laws that Parliament legislates. More specifically, there is a constitutional rule that the queen ought to act on ministerial advice.

This leaves us with a clash between two important and well-established rules, which normally pull in the same direction (I’m being charitable to Ekins and Laws, as the better view is probably that the first of these rules does not apply to the legislative context): 1. the monarch ought to act on ministerial advice; 2. the monarch ought not to withhold assent to legislation.

The resolution of the conflict is, in technical terms, a no-brainer. Rule 2 wins. Not because of any formal difference – both are long-standing constitutional conventions – but because it is more important. All constitutions have a hierarchy of rules. That is in part why they exist. Rule 1 is important, as it is designed to ensure that the monarch’s powers are not exercised in a way inconsistent with the wishes of elected representatives. But it cannot supervene on rule 2, which is one of the structural underpinnings of parliamentary democracy.

The constitution is built on the supremacy of parliament over the executive. That was centrally what 1688 decided. A big part of realising that achievement was a reduction over time in the real power of the monarch almost to vanishing point. One of the first things to go was the monarch’s so-called ‘negative voice’: the capacity, last used by Queen Anne (even then on the advice of ministers), to veto proposed legislation by refusing to give royal assent. Buckingham Palace recognises this. A letter to an anti-Brexit campaigner on 6 March 2017 restates the constitutional orthodoxy: ‘there is no question of The Queen, as a constitutional Sovereign, refusing the Royal Assent to an Act which has been passed by both Houses of Parliament.’

We expect the government to be able to retain the confidence of the Commons. If it cannot do so, that is a political problem (certainly for the government) but not a constitutional one. It is a situation that the principle of parliamentary supremacy anticipates. When push comes to shove, the constitutional position is clear: Parliament, not government, is supreme.

When we talk about supremacy we mean who has the authority to legislate: not who gets to draft the laws, but who gets to decide what counts as law. The situation that Ekins and Laws imagine is one marked not by failure or stasis – in which, for instance, no parliamentary agreement can be found (the situation we are still in fact in). In their scenario, legislation has been passed by Parliament, if in a politically – but not legally – unconventional way. What is said to justify overriding fundamental constitutional principle is the attempt by the Commons to seize power from the government. Constitutionally, there is no injury here to redress, for the simple reason that the relevant power – the constitutional authority to pass laws – was never the government’s to lose.

What Ekins and Laws suggest, in effect, is getting the monarch to thwart Parliament in the interests of the executive. At the level of principle, this is little short of monstrous. It invents for the 21st-century executive, out of the archaic form of the monarch’s ‘negative voice’, a power to veto legislation. They invoke a principle that the law should not be changed until both the government and Parliament have agreed that it should be. There is no such principle. The claim confuses the normal with the norm, how legislation is typically passed with the rules that govern the process: whether or not a statute is proposed by government is immaterial. It also assumes that the UK executive has a separate source of democratic legitimacy, like the elected (and veto-wielding) US president. But in the Westminster system, democratic authority is channelled through Parliament. Constitutionally speaking, we vote for MPs and a government is formed from among their number.

The proposal, flimsy and fanciful, may be risible as a constitutional proposition. But it is no joke. There is a serious undercurrent to all this. What animates the Judicial Power Project, with which Ekins is intimately associated, remains unclear. But it is not only the rise, as they see it, of judicial power. As Ekins’s writings on Brexit display, its targets seemingly include any institutional check on executive power, political as much as legal. This is not, to my mind, a programme of constitutional conservatism in the spirit of Blackstone or Burke. It is an anarcho-conservatism more familiar from the work of counter-revolutionaries such as Carl Schmitt. Authoritarian rather than conservative in disposition, it treats established constitutional forms and norms as fungible, even disposable, and presses exceptional moments in the direction of a central authority delivering the ‘will of the people’. For all the constitutional posturing, the object of the power so directed is to make it easier to realise a purified version of an imagined past.