UK Constitutional Law Association

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Sam Fowles: Can the Prime Minister Prorogue Parliament to Deliver a No Deal Brexit?


In recent days certain government backbenchers have proposed a new avenue to deliver a “no deal” Brexit. As Sir Edward Leigh put it:


“There are only two choices given the EU won’t change the deal and there’s no chance of parliament passing it. One is cancel Brexit: an intolerable denial of democracy. The other is leave without a deal on WTO terms on 31 October. But MPs, assisted by the Speaker, will block this. Solution: End this failed session immediately within a few hours of a new government and prorogue Parliament. Leave the EU on 31 October…”

While several Conservative leadership candidates have disavowed this course of action, Dominic Raab, one of the front runners, appears to have declined the opportunity to do so. It further appears that Andrea Leadsom, whilst Leader of the Commons, explored the implications of taking a similar course of action. The Speaker, John Bercow, has stated that he will not permit Parliament to be prorogued in such a way. Prorogation, however, is within the gift of the Monarch, not the Speaker. It is not clear what would happen if the Queen prorogued Parliament and the Speaker refused to be prorogued but it is certain that it would create a constitutional crisis.

Could such a crisis be worked out in the courts? The power to prorogue Parliament falls within the royal prerogative. This power was expressly preserved by section 6(1) of the Fixed Term Parliaments Act 2011. As established in Council of Civil Service Unions v Minister for the Civil Service [1984] UKHL 6 (“the GCHQ Case”), The prerogative is, with certain exceptions, subject to judicial review. As established in Bancoult (No. 2) [2008] UKHL 61, the same principles generally apply to a review of prerogative power as apply to the review of other government powers. Certain prerogative powers are, however, excluded from review. It is generally understood that these include matters of pure international law, the Royal Assent, and the use of “personal” prerogative powers. This third class includes the power to prorogue Parliament.

Does this make the “Brexit through prorogation” plan immune from judicial review? Not necessarily. Two avenues may be successful. First, as they did in R (Miller) v Secretary of State for Exiting the European Union [2017] UKSC 5 (pdf), the courts may determine the scope of the prerogative power even where that power is one of those excluded from the traditional principles of judicial review. The courts may determine that to prorogue Parliament so as to prevent Parliament from exercising control over Brexit is outside the scope of the prerogative power (the substantive reasons for this are set out below). Further, it was stated by the majority in Miller that the court could not accept that ‘a major change to UK constitutional arrangements can be achieved by ministers alone’. Parliament should be consulted on significant constitutional changes. Given that, by effect of Article 50, the UK will automatically leave the EU on 31 October, the government’s failure to stop it will create a substantial constitutional change by default. I do not think this argument is as strong in this case as it was in Miller, however, because it begs the obvious response that Parliament sanctioned the serving of a notice under Article 50 in the European Union (Notification of Withdrawal) Act 2017 in the full knowledge of the effect of Article 50. There has not been any subsequent Act of Parliament suggesting that the position has changed on that point.

Second, there is nothing to indicate that the Queen will exercise her personal prerogative to prorogue Parliament otherwise than on the advice of the Prime Minister. I would argue that the decision to advise the Queen to prorogue Parliament is separate from the Queen’s decision to do so. The latter could (constitutionally speaking) be made independently of the former. The courts may, therefore, entertain a judicial review of the Prime Minister’s decision to advise the Queen to prorogue Parliament without trespassing on the personal prerogative of the Monarch herself. Given the analysis below, the courts will have good reason to find such a constitutional fix.

What of the substantive grounds for review? It is almost certainly beyond the power of the Prime Minster to advise the Queen to prorogue Parliament in order to frustrate the will of that same Parliament. It is also arguably outside the scope of the Queen’s prerogative power to exercise it so as to frustrate the will of Parliament. As the House of Lords held in R (Fire Brigades Union et al) v Secretary of State for the Home Department [1995] 2 A.C. 513 (albeit in the case of a clear statutory steer from parliament), the executive is not permitted to use prerogative powers to frustrate the will of Parliament. Both Houses of Parliament have expressed the view that a “no deal” Brexit should not be permitted. Parliament has exercised control over the process of Brexit so as to ensure a “no deal” Brexit is avoided. It will likely seek to do so again in October. The act of advising the Queen to prorogue Parliament before (and across) 31 October would have the effect of excluding Parliament from the Brexit process.

Parliament’s democratic mandate is fundamental to the UK constitution. In Sir Jeffrey Jowell QC’s words, Parliamentary sovereignty “is the stone upon which our Constitution is not writ”. The government holds office because it is able to command a majority in the House of Commons. The Commons hold office because they hold a mandate from those they represent. Legitimacy flows upwards from the electorate. As Lord Hope of Craighead put it in Jackson v Attorney General [2005] UKHL 56 (pdf) at 126:

“It must never be forgotten that this rule [of recognition] … depends upon the legislature maintaining the trust of the electorate. In a democracy the need of the elected members to maintain this trust is a vitally important safeguard. The principle of parliamentary sovereignty… is built upon the assumption that Parliament represents the people whom it exists to serve.”

In the light of this, it seems absurd to suggest that the Prime Minister has the power to advise the Queen to take an action that would exclude Parliament from expressing its view (and potentially exercising its power to control the actions of the government) in relation to the most significant constitutional matter in a generation. Similarly, given the democratic basis of the constitution, and parliament’s fundamental position in that, it seems very difficult to argue that the Queen’s prerogative power extends to proroguing Parliament so as to silence Parliament in relation to a major constitutional issue.

It may be argued that, although Parliament has, in the past, indicated that it opposes a “no deal” Brexit, it is not for the courts to read such an intention into the future. In the European Union (Withdrawal) (No. 5) Act 2019 Parliament, in effect, ordered the Prime Minister to seek an extension to the Article 50 TFEU process so as to avoid a “no deal” Brexit on 12 April. Similarly, various motions all related to 29 March or 12 April. The order in the 2019 Act only mandated a single action.  It might be argued that, while Parliament ruled out a “no deal” Brexit in April, it has not done so indefinitely. The statements of various MPs do not carry the same weight as an Act of Parliament. Indeed, as Maddy Thimont Jack has pointed out, at the Institute for Government, it is not clear that Parliament will be able to take the same approach to a “no deal” Brexit in October as it took in March and April.

Such an argument, however, seems rather semantic. The core of the issue is the exclusion of Parliament from a matter of historic constitutional importance. The harm at which a review would take aim is not simply the frustration of Parliament’s will, but the fact that Parliament will be prevented from establishing a position at all.

The act of advising the Queen to prorogue Parliament would also, likely, be reviewable on the “bad faith” ground. The Prime Minister has a duty to exercise her powers in good faith (see R(C) v Secretary of State for Health [2000] 1 FCR 471 at 23). Advising the Queen to prorogue Parliament so to prevent it from frustrating the Prime Minister’s agenda cannot possibly be considered a good faith exercise of the power. There may be other grounds for review, but these seem to be the leading contenders.

A review such as this would undoubtedly push the boundaries of constitutional law. It must tease out numerous technical and principle issues (I have not begun to discuss the proper remedy, for example). It would, however, be an appropriate response to an extraordinary constitutional moment. It is, indeed, in the heat of such moments that the UK’s evolutionary constitution is forged.

Sam Fowles is a Barrister at Cornerstone Barristers and a Fellow at the Foreign Policy Centre.

(Suggested citation: S. Fowles, ‘Can the Prime Minister Prorogue Parliament to Deliver a No Deal Brexit?’, U.K. Const. L. Blog (10th Jun. 2019) (available at

22 comments on “Sam Fowles: Can the Prime Minister Prorogue Parliament to Deliver a No Deal Brexit?

  1. Pingback: Brexit Highlights 3 – 9 June 2019 | Middle Temple Library Blog

  2. Michael
    June 10, 2019

    I am wondering about the the Prorogation Act 1867. Is this still good law? If so could the power to prorogue Parliament flow from this Act rather than the prerogative (in light of De Keyser’s Royal Hotel)? Would that change the assessment of the PM’s powers?

  3. Roger
    June 10, 2019

    It’s not denying the will of Parliament to allow the notice in Article 50 to take effect when Parliament itself voted so heavily to do so. In fact it seems to me that it is Parliament that is out of step here.

    It is extraordinary that such steps are even having to be talked about because of the behaviour of MPs, who are failing to keep to the undertakings they made.

    It is MPs that are seriously st fault.

    • Tony
      June 11, 2019

      Parliament didn’t legislate to require the Article 50 notice to be served in the European Union (Notification of Withdrawal) Act 2017 – it merely granted the Prime Minister the discretionary power to do this. In addition, because the Article 50 notification can be revoked, it’s not the case that Parliament has mandated EU withdrawal to take place. Parliament is free to reverse any of the legislation it passes. Mandates and “undertakings” don’t apply to Parliament – that’s what Parliamentary Sovereignty means.

      • Roger
        June 12, 2019

        I accept your technical points.

        It remains the case that MPs are failing to meet their undertakings to an extent that proroguing Parliament has been raised as a serious proposition.

  4. JohnAllman.UK
    June 10, 2019

    It would appear that in EU law, the UK will leave the EU at the end of the final extension to the Article 50 notice period (which I will call EU Brexit), unless Article 50 notice is revoked beforehand in compliance with any British constitutional requirements, which I will refer to as “cancelling EU Brexit”.

    In UK law, the UK leaves the EU on the statutory “exit day” defined in section 20 of the Act, as amended, which I will call UK Brexit. UK Brexit and EU Brexit both used to be 29th March 2019.

    It is important that EU Brexit and UK Brexit should be synchronised so that they happen simultaneously, if they happen at all.

    Both Houses of Parliament could theoretically pass primary legislation to repeal the present primary legislation provision whereby the UK Brexit occurs on exit day. This I call “cancelling UK Brexit”.

    EU Brexit will be on WTO terms unless a withdrawal agreement agreed between the government and the EU subject to ratification by the latter is first ratified in accordance with the UK constitution. UK Brexit will be on WTO terms unless the House of Commons votes beforehand to approve the ratification of any withdrawal agreement.

    The date of UK Brexit cannot be amended without secondary legislation in both houses of Parliament.

    The date of EU Brexit cannot be amended without the consent of the EU.

    Amending the date of EU Brexit without also amending the date of UK Brexit would be undesirable.

    I am going to argue, if need be by way of judicial review, that cancelling EU Brexit requires primary legislation, passed by both Houses of Parliament. I hope to win.

    Assuming I win, it appears that the only outcome that can be procured without Parliament’s further co-operation with government (e.g. procured whilst Parliament isn’t sitting, or if Parliament hasn’t done beforehand all that is needed before being prorogued) is EU Brexit and UK Brexit on 31st October, on WTO terms.

    The new Prime Minister will inherit the situation in which Parliament, which has enacted the present UK law status quo, thus authorising the giving of Article 50 notice that has caused the present EU law status quo, has expressed a non-binding distaste (in the Commons at least) for the UK’s leaving the EU on WTO terms, but has so far been unwilling to enable any of the remaining possible outcomes. If those circumstances continue until Parliament rises for the conference season, I for one don’t want Parliament to sit between the end of the conference season and EU Brexit and UK Brexit, simultaneously on 31st October.
    Apart from passing meaningless advisory votes counselling against accepting WTO terms, when no other legal option remains, mainly because Parliament has done none of the various things it could have done to make a different outcome lawfully achievable, what earthly use is Parliament, in the final run-up to 31st October.

    Mrs May’s policy u-turn during what was supposed to be the final week before Brexit shocked me. Her further policy u-turn that caused me to attend court on 10th April fearing I needed to battle to save Brexit myself, was even worse. I do not want an impotent Parliament putting on a show, panicking like headless chickens next time we reach that part of the loop. I want an orderly Brexit.

    I do not mind at all the government’s ministers being left in peace, for the last three weeks of Brexit planning.

    I was in court two days before the interim EU Brexit Day and UK Brexit Day of 12th April, seeking to establish that primary legislation was a constitutional requirement in order to cancel EU Brexit. I fear I may need to resume that task before long. That needs to be tested in court in good time, preferably not on 29th October, because the government has ignored the pre-action correspondence and no law firm has taken on my Miller-in-reverse challenge, allowing history repeat itself.

    For more information about my intended judicial review, see:

    Saving Brexit

    Schrödinger’s Brexit

    I’m taking the PM to court

  5. Tony
    June 10, 2019

    Parliament didn’t actually “sanction” the Article 50 notice to be served in the European Union (Notification of Withdrawal) Act 2017 – it merely granted the Prime Minister the discretionary power to do this. In addition, because the Article 50 notification can be revoked, it cannot be said that Parliament has mandated that EU withdrawal take place, let alone that it should occur by a particular date.

    Because of this, the principle stated by the majority in the Miller case (i.e. “a major change to UK constitutional arrangements can be achieved by ministers alone”) remains applicable to issues regarding the lawfulness of prorogation.

    • Jerzy Kolodziej
      June 11, 2019

      Parliament did not “sanction” the Office of the Prime Minister to give notice. The power was a discretionary conferred power that was subject to the usual requirements of any administrative decision and subject to review. Importantly, such a decision is also subject to the provisions of A50(1) that requires notice to be “in accordance with the constitutional requirements” of the country leaving.

      There are several obstacles. I would question whether prorogation to avoid Parliamentary scrutiny was compatible with the Bill of Rights 1688[9] and the Supreme Court Ruling in Miller. I would also question whether it fulfilled the purposes and intentions of the EU (Withdrawal) Act itself.

      How would the CJEU rule on the legitimacy of A50 notice if they were required to?

      I accept the author’s differentiation between the decision of the Prime Minister to advise Her Majesty and the that of the Her Majesty herself. Her Majesty would be bound to act on the advise unless it were quashed by the courts.

      In practical terms, there may be difficulty in preventing the illegal prorogation of Parliament without some sort of injunction?! The situation would be highly unusual.

      I totally reject that the courts would accept the legitimacy of prorogation for any purpose ulterior to its ordinary usage. The underlying foundation of constitutional order would be undermined if a government could simply avoid Parliament to establish authoritarian control of the law. It would not be acting in good faith. In my view it would be precisely what the Bill of Rights was enacted to avoid:

      Dispensing Power.
      That the pretended Power of Suspending of Laws or the Execution of Laws by Regall Authority without Consent of Parlyament is illegall.

      Frequent Parliaments.
      And that for Redresse of all Grievances and for the amending strengthening and preserveing of the Lawes Parlyaments ought to be held frequently.

      The purpose and intention is to ensure Parliament is not bound or silenced.

      Finally, there is the question of where it would leave us if such a prorogation were to effected. At some point, Parliament would have to enact laws to facilitate the Brexit process, in the circumstances that Parliament had been deliberately frustrated from doing so at the appropriate time. It would be a full scale constitutional crisis on an astonishing scale.

    • Paul W
      June 23, 2019

      “Parliament didn’t actually “sanction” the Article 50 notice to be served in the European Union (Notification of Withdrawal) Act 2017”

      On the contrary, the Act did ‘sanction’ i.e. permit the Article 50 notice to be served. No further legislative action was required to satisfy the majority judgement in Miller and thus to satisfy Article 50(1)’s ‘constitutional requirements’.

      Of course Parliament can change its mind, and proroguing it to prevent it passing the necessary legislation would seem to be acting in bad faith.

      But the Court would not necessarily invoke the Miller principle again. After all, by the Notification Act Parliament has decided that it approves of Brexit. It has had plenty of time since then to change its mind. The Crown would have a tolerable argument that it is now in the national interest to have a period of certainty pending Brexit Day. The closer October 31 approaches, the stronger that argument becomes. The Court may conclude it doesn’t have a dog in this constitutional fight.

      The best it might do is stay the PM’s hand so as to give Parliament time to table a vote of No confidence under the Fixed Term Parliaments Act.

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  8. Gary Phillips
    June 27, 2019

    Sir Edward Leigh’s suggestion that a new Prime Minister could be commissioned who has not demonstrated that he has the confidence of the Commons and who intends to act to prevent the Commons from expressing that confidence or lack of it, can be dismissed as fantasy. It would be a coup.

    It seems clear that the Leader of the Opposition intends immediately to test whether a new Prime Minister has the confidence of the Commons.

    The more interesting question is what happens if the new Prime Minister wins that initial vote with the support of MPs who indicate that their confidence would be withdrawn if the Prime Minister attempted to produce a No Deal Brexit by prorogation and then the Prime Minister later seeks a prorogation.

    The answer seems to be the fundamental implausibility of a “surprise” prorogation given that the Prorogation Act 1867 does not apply to a prorogation at the end of a session. One would end up with a televised version of the Arrest of the Five Members or the Dissolution of the 1681 Oxford Parliament.

    The only realistic scenario in which one could see the courts having to adjudicate on a prorogation issue is if a Prime Minister persuades the Commons to acquiesce in a prorogation for a new Session commencing before 31 October, and then implements a prorogation by proclamation of the new Session before it meets to a date after 31 October under section 1 of the Prorogation Act 1867. That statutory prorogation looks more amenable to judicial review and it is difficult to see such a scenario arising except upon a breach of faith by the the Prime Minister to the Commons of the terms on which the Commons allowed the earlier prorogation to proceed.

    • Roger
      June 27, 2019

      The fact that MPs have undermined the people and the government by vociferously setting themselves against a no-deal exit is what I find most appalling.

      Both major parties committed to acting on THE people’s vote of 2016 in the 2017 election but did nothing to ensure the people it sanctioned to represent them were committed to that objective.

      Both major parties are guilty of complacent mismanagement. They may yet pay the ultimate price. MPs who continue to seek to avoid no-deal are contemptuous imbeciles. Whatever they think, however bad they (mistakenly) think Brexit will be for the country, their first commitment should be to carry out what the people voted for. If they can’t even get us out after more than 3 years, let alone resolve the future relationship, Parliament should be shut down permanently as useless.

      A new seat of government and people’s representatives needs restructuring and locating in purpose built premises in the heart of the country, ie not London, which has shown itself to be detached from the rest of us. Visit Parliament and you’ll see how easy it must be to become lost in the sea of old history and forget you lead a purposeful independent vibrant modern 21st century country. Unless MPs stand beyond a line in the floor, they’re not allowed to speak! The place is a museum.

      And at some point grasp the nettle of BBC funding – it no longer justifies unquestioning excessive public finance as its neutral political stance no longer exists.

  9. Julian Cole
    July 1, 2019

    If the Queen forces a “no-deal Brexit” on the 16M who voted against Brexit, and the 13M who did not vote, Her Majesty could become the last Monarch of the United Kingdom. Is this a risk she is willing to take?

  10. Patrick Ostendorf
    July 7, 2019

    I wonder why prorogation would be necessary anyway if a new PM wants to deliver a no Brexit deal given that this is simply the default option. Could Parliament force the government to submit a revocation of the Art. 50 notice to Brussels respectively request a prolongation in accordance with Art. 50 (3) TEU??

    • Tony
      July 17, 2019

      Yes, Parliament can enact a statute requiring the government to revoke the article 50 notification because it would be imposing an enforceable legal duty on the government.

      What’s more interesting is that Parliament could, alternatively, enact a statute that executes the revocation “decision” directly by operation of law (i.e. without requiring action on the part of the government). The same statute could also grant legal authority to any office holder to notify the EU Council of the revocation decision and require that office holder to submit that notification. If the office holder was not a member of the government (e.g. an officer of Parliament) this would have the effect of conclusively revoking article 50 without involving the government at all.

      • JohnAllman.UK
        July 18, 2019

        My question remains unanswered. Can the government revoke Art. 50 notice if Parliament does not enact that it may or must do so? I am seeking a declaration to the effect, no, it cannot. The lack of interest in this test case, here and elsewhere, I find staggering.

      • Tony
        July 22, 2019

        Yes, the government can revoke Art. 50 notice even if Parliament does not enact a statute stating that it may or must do so. This is because the application of EU treaties to the UK is a matter of international law. A statute is required to dis-apply the domestic effect of EU law in the UK, but this is a separate matter.

      • JohnAllman.UK
        July 26, 2019


        You say, “Yes, the government can revoke Art. 50 notice even if Parliament does not enact a statute stating that it may or must do so. This is because the application of EU treaties to the UK is a matter of international law.”

        Roughly speaking, in Miller, the government argued unsuccessfully that the government could give Art. 50 notice even if Parliament didn’t enact a statute stating that it may or must do so. This was because the application of EU treaties to the UK was a matter of international law. Why the asymmetry that you assert, whereby an argument that had failed in one direction, would succeed if applied in the opposite direction?

        I have now published my claim form, by the way.

        Blocking Brexit

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  12. JohnAllman.UK
    July 13, 2019

    Yesterday, I served a sealed Judicial Review claim form on the Prime Minister and the Brexit Secretary. I am asking the court for a declaration that the Royal Prerogative alone does not empower the British government to revoke Article 50 notice of the UK’s intention to leave the EU, because the constitutional requirements for such a revocation include the prior enactment of a statute permitting or requiring revocation, nothing less than an Act of Parliament being sufficient.

    There has far too much talk of “Parliament” “blocking” a “no deal Brexit”. Parliament, both houses, and the Queen have enacted that there will be a no deal Brexit, unless certain conditions are met. The only way to change that legal position would be another Act to be enacted.

    That’s what I say. Unless, on the papers, a judge rules my application totally without merit, there’ll have to be a hearing now.

    Parliament (both houses) have enacted Brexit, with or without a deal. The Commons has rejected the only deal on offer, tantamount to voting for no deal. There are only four possible outcomes: no deal Brexit, the Commons voting for a Withdrawal Agreement that is actually on offer, further extensions, and canceling Brexit.

    I have decided I can no longer put up with news coverage that moots cancelling Brexit, never mentioning what the constitutional requirements would be for Brexit to be cancelled. I say that an Act is required, not just an adhoc division on a motion in one of the two houses of Parliament saying that the Commons that enacted Brexit has got cold feet and wants to “block” it now. I’ve got no sense out of HMG in 3 months of asking questions, so I’ve resorted to this litigation.

    Who will help me?

  13. Neil O'Brien
    July 13, 2019

    I am not a lawyer, though I read law after retirement from the fire service. Having ploughed (struggling, sometimes!!) through the forgoing arguments proffered by learned and honourable persons as to the validity of the use of the Royal Prerogative in respect of Article 50, nowhere in any of the arguments have I found any reference to the result of that most purest form of democracy: the referendum which told the executive and legislature, in no uncertain terms that the majority of the electorate voted ‘Leave’. There was only one question to answer: remain or leave and whatever reasons each voter had for his or her decisions was immaterial. The outcome of that referendum is democracy in its purest and inviolable state. That members of parliament, since that referendum, have sought and continue to seek to deny the fulfilment of this historically vital ‘Plebiscitum’ is flying in the face of the very concept of democracy and makes a mockery of the so-called ‘Mother of all Parliaments’ upon which many democracies around the world have founded their own. If ever the concept of the Royal Prerogative in its purest form should be decreed without further question, it is NOW!
    My apologies for butting in amidst this very high level legal argument but I do enjoy reading them.

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