UK Constitutional Law Association

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Kenneth Armstrong: Push Me, Pull You: Whose Hand on the Article 50 Trigger?

Kenneth ArmstrongThe days since the outcome of the British referendum vote to leave the European Union have seen much speculation over the law and politics of withdrawing from the EU under Article 50 TEU. Two rather separate strands of speculation have begun to appear. On the one hand – and driven by an increasing acceptance that Article 50 TEU will not, as previously intimated, be triggered in the immediate aftermath of the vote – there is conjecture over whether the UK’s hand can be forced to squeeze the trigger and initiate the withdrawal sequence under Article 50. On the other hand, there is some suggestion that Article 50 may not be triggered because Parliament could seek to veto notification to the European Council. We seem to have entered a Doctor Dolittle phase of push me, pull you law and politics.

The analysis below is not presented as a legally watertight argument, not least because the fast moving pace of the discussion demands reactions, without the time necessary to fully develop or defend a position. As the process evolves, so too will the analysis. But to summarise my position, it is this. First, that it is not inconceivable that the European Commission might find itself contemplating bringing infringement proceedings against the UK in a situation where – as envisaged by the Vote Leave Brexit ‘roadmap’ – the UK took steps to implement a decision to withdraw within the internal law of the UK without triggering the Article 50 TEU notification. Second, if Parliament was to be the body having the ultimate authority over whether the UK remains within or leaves the European Union, what was the point of the referendum?

Push Me

The fundamental starting point is that no other Member State and no EU institution has the power to compel the UK to withdraw following the referendum on the 23rd June. This is so for two reasons.

First, the notification under Article 50 TEU is dependent upon a Member State taking a decision to withdraw ‘in accordance with its own constitutional requirements’. Within the UK constitutional framework – and in the absence of anything in the European Union Referendum Act 2015 detailing what the consequence of the referendum would be – the referendum is not legally binding as such. In that sense, and within the UK’s political constitution, it is for the government of the day to act having regard to the will expressed by voters in the referendum. With the Prime Minister announcing his resignation it is, in effect, being left to the new Prime Minister and his or her government to make the withdrawal decision and to notify the European Council in terms of Article 50.

Second, nothing in Article 50 empowers any party other than the withdrawing state to trigger Article 50. This, of course, leads to the obvious question of what other EU Member States and EU institutions should do in light of the referendum but in the absence of an Article 50 notification.

Wisely, political leaders have accepted that there will be no immediate triggering of Article 50. In part, this is simply to avoid things being done reactively and in haste, and in part to allow the politics of this to play out in the UK. The latter point is especially important given the essentially political nature of the UK constitution. Perhaps the hope might be that in fact the politics will change and that the UK will not in fact withdraw. The possibility of an autumn general election might indicate a shift in popular opinion which, by itself, or in combination with another referendum, might yield a different result. All of which is speculation, but the essence of the pause is simply to let the internal politics of the UK play out as the turbulence following the referendum result subsides.

But what would happen if time passed and no letter was sent to the President of the European Council or no statement made to the European Council with the intention of triggering Article 50? As Donald Tusk made clear in his statement in the morning of the 24th June, the unity of the EU 27 is paramount and, rightly, EU Member States could expect clarity over not just the future position of the UK but of the EU as a whole with or without the UK.

The key issue from a legal polnt of view is what inference to draw from the word ‘shall’ in Article 50(2) TEU. Is the notification of a decision to withdraw merely the procedural step to be taken once a withdrawal decision has been made – reflecting the essentially facilitate nature of Article 50 – or is there a mandatory procedural obligation on a state to notify the European Council once a decision to withdraw has been made?

There is good reason to treat the word ‘shall’ as facilitative especially in the period being given for the UK to formally decide to withdraw. But once we get beyond say 5-6 month and EU leaders and institutions demand clarity, a more prescriptive meaning may begin to be attached to Article 50(2). This would be especially so were it to be clear from decisions being taken by the UK government to act on the referendum such that it was clear that the government was implementing a decision to withdraw. Thus would be particularly clear if any attempt was made to legislate to amend the European Communities Act 1972 to begin a process of restricting the application of EU law to the UK. In such circumstances, it cannot be excluded that the European Commission might commence infringement proceedings against the UK under Article 258 TFEU alleging a breach of the procedural obligation under Article 50(2) TEU; a breach of substantive obligations under the treaty in the event of the UK passing legislation in conflict with EU law but without actually having withdrawn from the EU; and perhaps also a breach of the principle of ‘sincere cooperation’ under Article 4(3) TEU.

It should be recalled, however, that the result of infringement proceedings under Article 258 TFEU is declaratory and could not compel the UK to act. The action for failure to act under Article 265 TFEU lies against EU institutions and not Member States.

The idea that we would ever find ourselves in a situation in which the Commission was contemplating infringement proceedings would not augur well for future negotiations. And it is not a situation that we should expect. Either the domestic politics of the UK will play out and the Article 50 notice will be initiated by the new Prime Minister or, by some means, the UK will have decided not to withdraw from the EU.

Pull You

But let’s turn the situation around and imagine that the UK government is keen and ready to pull the trigger on Article 50. Are Barber, Hickman and King right to assert that this cannot be a matter for government alone but something that demands parliamentary authorisation?

Their argument is an intriguing one but I don’t think the claim is compelling. Even without addressing the elegant detail of their argument there is, I think, simply an intuitive point. If, normatively, we think parliament should have the decisive say on whether the UK stays in or leaves the EU, why on earth was that constitutional, as well as normative, principle departed from in entrusting the decision to a referendum?

If, as the authors clam, statute trumps prerogative, surely once you depart from parliamentary sovereignty by holding a referendum, direct democracy trumps representative democracy? Of course, the constitutional response is that parliament was not giving up its responsibilities because, as intimated previously, the referendum is only advisory. But who exactly is the electorate advising? It cannot really be parliament because the electorate gives its input to parliament through the medium of the election of MPs and their representative role within parliament. This must, instead, be more in the nature of advice to government. And the decision of the electorate that the UK should leave the European Union is its advice to government which it should act upon. For parliament to frustrate that would be to deny the whole point of the exercise. Conversely, to say that parliament needs to be the body that acts on the advice and authorises the executive to trigger Article 50 seems to be little more than constitutional face-saving when confronted by the rampant reality of direct democracy in action.

Parliament will, of course, be engaged in the adoption of consequential legislative changes including the repeal of the European Communities Act. That the withdrawal decision will have an effect on rights and duties which the UK parliament has enacted by statute does not give parliament the right to authorise or not to authorise a government to trigger Article 50. It simply means that it will be for parliament to make the necessary domestic legislative changes to give effect to changes in the UK’s international obligations.

Kenneth Armstrong is Professor of European Law, University of Cambridge

(Suggested citation: K. Armstrong, ‘Push Me, Pull You: Whose Hand on the Article 50 Trigger?’ U.K. Const. L. Blog (27th Jun 2016) (available at

20 comments on “Kenneth Armstrong: Push Me, Pull You: Whose Hand on the Article 50 Trigger?

  1. Neels Kriek
    June 28, 2016

    Professor as a lay person – should a court decide whether Parliament should act on the referendum decision or whether it was only advisory? Will such a court not consider what happened in the previous referendum – country decided to join and Parliament then enacted that decision, consequently based on previous actions the precedent has been set for them to also act now and not see the decision solely as advisory?
    PS – I am for remain

    June 28, 2016

    Previous referendum was actually taken once we had already joined…

    This could end up being decided in court. If the new PM attempted to activate Art.50 without parliamentary approval I would expect someone to start judicial review proceedings as he is clearly acting outside his powers.

  3. Laypersonlaw
    June 29, 2016

    The refer sum was clearly advice to Parliament just as others have been. The AV referendum even included provisions to trigger a Legislative process, a Parliamentary matter. With no such provisions in this referendum, it must have been Parliament’s intent to reserve the legal decision. In the alternative it seems impossible to argue that Parliamemt had intended the result to be an instruction, a mandate to government when it was silent on such an instruction.
    Parliament can of course sk the people their view on any individual matter of importance given general election results present many positions on many issues.
    We would be in dangerous territory if we were to say results of anyopular vote (referenda or elections) provided a direct mandate to govern,net to act unless Parliament has expressly designed it so. It has done so in the past but not in this case.
    No “decision” means the UK does not yet qualify to invoke Art.50. Any govt that invokes it without Parliamentary consent risks being taken to court, perhaps a European one. The irony of this and the idea that Brexit is about Palriamentary Sovereignty yet some voting to leave believe Parliament should not now have a role it had obviously intended it would.

  4. Laypersonlaw
    June 29, 2016

    Additionally, you presuppose that representative democracy is merely a process in lieu of direct democracy; what’s the role of Parliament if we ask the people direct? Representative democracy is so much more than a process we employ to avoid the inconvenience of having people decide everything direct. Parliament is more deliberative. It debates. Dare I say it DOES listen to experts. It considers what it understands to be the views of the people and its own consideration of their interests and makes a decision. If that public opinion is represented by letters, lobbying, protests outside, a general election or plebiscite matters not (unless Parliament says so). The political consequences of acting contrary to a referendum outcome is for members to consider but ought not diminish Parliaments rights.

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