Professor Richard Ekins is Associate Professor of Law at the University of Oxford, and Head of Policy Exchange’s Judicial Power Project. Sir Stephen Laws KCB, QC (Hon) is Senior Research Fellow at Policy Exchange and formerly First Parliamentary Counsel.

The next Prime Minister is likely to be committed to the UK leaving the EU on 31st October with or without a deal, partly on the grounds that this commitment will help secure a (better) deal.  How, apart from by voting for a deal, might the House of Commons prevent a No Deal exit?

The new government may face a vote of no confidence, which, if lost, could lead to the formation of a different government or, more likely, to a general election.  But by the time an election is held the UK might have left the EU without a deal. A more appealing option, especially for many Conservative MPs, would be to legislate (against the wishes of the government) to require the Prime Minister to ask for another Article 50 extension from the EU.  

The concern that many MPs have, understandably enough, is that the new Prime Minister might at some point call time, proroguing Parliament, likely sometime in October.  This might prevent a vote of no confidence from being called (and lost), might prevent a vote of confidence in a new government from being moved or might prevent a bill requiring the Prime Minister to ask for an extension from being introduced or, having been introduced, from being enacted

Over the weekend, a new plan was reported for preventing prorogation, and thus preserving the opportunity of the Commons to attempt to prevent a no-deal exit.  The plan, said to be devised by Dominic Grieve, is to amend the Northern Ireland (Executive Formation) Bill, which is before the Commons today, to require government to report back to the Commons in October on progress towards the restoration of devolved government in Northern Ireland.  The hope seems to be that this would make it unlawful for the government to secure the prorogation of Parliament. 

This is an ingenious plan.  Will it work? It is intended to work by imposing a duty on the government which cannot be discharged if Parliament is not sitting when the report is due in. The argument runs that the Prime Minister cannot recommend the prorogation of  Parliament without undermining this statute, a legal limitation which, it is assumed, the courts would uphold in litigation if need be. It is not clear how the amendment would work if the Commons were not sitting because it had adjourned or been dissolved.  

The plan may be too clever by half.  If Parliament is prorogued at the relevant time the Secretary of State would be unable to meet her statutory reporting duty.  It does not follow that Parliament has impliedly curtailed the prerogative power to prorogue Parliament. Instead, one might simply say that one unintended side-effect of the use of the prerogative is that the Secretary of State is unable to report, for there would be no House in session to which to report.  

Various statutes impose duties on ministers to report or lay documents before a House of Parliament that cannot be performed while the House is not sitting.  In ordinary times, it would be very unlikely that those enactments would be construed as limiting the prerogative power to prorogue. But clearly these are not ordinary times and the question might be how far the current, somewhat fraught, political context informs how MPs and others understand today’s legislative proposal. 

This amendment is being proposed, it seems obvious, to prevent prorogation.  But it is important to note that the amendment will not attempt expressly to limit the prerogative power to prorogue.  Any such amendment might be outside the scope of the Northern Ireland (Executive Formation) Bill. If the limitation is to be accomplished it will be indirectly, by a side-wind.  The risk for the sponsors of the amendment is that it fails to articulate, even by implication, an intention to limit prorogation. The so-called “principle of legality” is sometimes misused, but contains a kernel of good sense. The courts should be slow to conclude that Parliament intends to disrupt the existing constitution or to conclude that constitutional change to one of the higher prerogatives is implied.  

In a famous case, Lord Hoffmann reasoned that the rationale for the principle of legality was that while a sovereign Parliament could enact anything it pleased, including legislation restricting fundamental rights, it had to do so openly and had to face the political cost of its actions.  It is arguable that it is not for the courts to police Parliament’s political accountability, but there is force in the idea that Parliament should be direct in articulating its lawmaking intentions.

What this means is this: if MPs want to limit the prerogative power to prorogue Parliament, they should say so in terms, not indirectly with a nudge and a wink.  This, in turn, raises another important consideration. If MPs did attempt to change directly the prerogative power to prorogue, the bill in question would clearly need “Queen’s consent” under the rules that apply in both Houses. Procedurally, the government has an absolute veto on legislation that limits prerogative powers, including power to prorogue.  Queen’s consent is required in each House and is different from Royal Assent.

If, as seems possible, there is no Queen’s consent, the amendment in question should not be understood to limit the prerogative.  One cannot have it both ways: if the point of the amendment is to limit the prerogative then Queen’s consent is required, but if Queen’s consent is not given, then the amendment should not be understood to limit the prerogative by implication.  

It is unknown at the time of writing quite what form the amendment will take or whether it will have the numbers to pass in the House of Commons.  But if it is enacted, it will introduce the risk of litigation in October if there were a proposal to prorogue Parliament. This would place the courts, again, in the midst of political controversy.  They might misconstrue the amendment and would be exposed to political criticism. They should not be put in this position, and MPs today have a duty to insist that any legislation that attempts to limit the prerogative should say so clearly and should only be enacted in strict accordance with the rules.