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Revoking Article 50: Explaining the Possibility to Stop Brexit

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About The Author

Maya Moss (Regular Writer)

Maya holds an LLB from Durham University and recently completed an LLM in European Law at the University of Edinburgh. Her main interests lie in constitutional and European law, and issues of civil and political rights. A hopeless foodie, she enjoys listening to jazz and spouting useless Harry Potter trivia.


It's time [the Tory government] made up their mind.

Guy Verhofstadt

On 4 December 2018, Advocate General (AG) Campos Sánchez-Bordona delivered his opinion on Case C-621/18, suggesting that the notification of withdrawal from the EU by the United Kingdom can be unilaterally revoked. In considering a question which has been debated academically since the Prime Minister triggered Article 50 TEU – thereby initiating the procedure for the United Kingdom to leave the EU – the AG’s opinion advises the European Court of Justice (CJEU) to allow for such revocation, opening a possible third door for MPs in the upcoming debate on the withdrawal agreement. Although the opinion itself is not legally binding, it is clear from the subsequent judgment of the CJEU, published 10 December 2018, that the opinion has been largely adopted by the Court.

The Case

The case in which the opinion was given was initially brought by a number of Scottish politicians. It seeks to determine whether it is possible for the UK, of its own volition and without the consent of the European institutions, to cancel Brexit and remain an EU Member State. Article 50 itself is silent on this issue, and despite the AG’s opinion there are arguments suggesting that Article 50 cannot be interpreted as allowing such revocation.

The relevant sections of Article 50 state:

  1. Any Member State may decide to withdraw from the Union in accordance with its own constitutional requirements.
  2. A Member State which decides to withdraw shall notify the European Council of its intention. In the light of the guidelines provided by the European Council, the Union shall negotiate and conclude an agreement with that State, setting out the arrangements for its withdrawal, taking account of the framework for its future relationship with the Union...

The case deals primarily with Article 50(2), and what status the notification has after it has been communicated.

The Opinion

AG Campos Sánchez-Bordona’s opinion itself covers numerous contentious issues, both with regards to the admissibility of the request for a preliminary ruling, the substance of the matter, and what conditions must be attached to allow for unilateral revocation.


Unsurprisingly, the British government contended that the matter of revoking notification of Article 50 was inadmissible, primarily on the basis that the matter was hypothetical and academic, and that finding the matter admissible would run contrary to the system of remedies in the Treaty, which do not envisage the CJEU providing advisory opinions on constitutional matters.

The AG, however, found the case admissible, on the basis, inter alia, that the decision was of ‘practical importance’, and might clarify what options Members of Parliament (MP) will have in the impending vote. The CJEU agreed the case was admissible, albeit for a slightly different reason: it was emphasised that it was not for the CJEU to question the process of the national court in determining admissibility, and that the question was undoubtedly relevant as it concerned interpretation of primary EU law.

The substance

On the basis of international law, the AG interpreted Article 50 to suggest that notification may be unilaterally revoked. For the purpose of this piece, the references to international law will not be extensively discussed; suffice to say that the AG suggests, although the EU and several Member States are not parties to the Vienna Convention on the Law of Treaties (VCLT), that instrument may be used as an interpretive guideline.

The overarching argument of the AG contends that unilateral revocation of notification remains possible until a withdrawal agreement is formally concluded. In the context of the UK, such a possibility remains until the British parliament and the EU have both accepted the draft agreement.

Withdrawing itself is unilateral in nature, and the AG considers this conducive to the possibility of revocation of notification also being unilateral. This, he suggests, is a manifestation of the sovereignty of the Member State in question. Given that the ‘procedural obligations’ of Article 50 are limited – merely formal notification (presumably in writing) and the two-year waiting period – AG Campos Sánchez-Bordona argues that this indicates a retention of control by the withdrawing Member State.

Large parts of the argument rely upon the specific wording of the provision, focusing on the word ‘intention’, and the fact that intentions are not definitive; although the expression of intention might create an expectation, there is no obligation to maintain that intention. The AG argues that if it was intended to be otherwise, then decision would be the operative word in the provision: drafters could have framed it as ‘shall notify that decision’ (or something similar).

The AG confirms that revocation must also be in accordance with Member State constitutional requirements. He suggests in this vein that if the national Supreme Court held that the initial decision to withdraw was not made constitutionally, it would be invalid, and that the Member State ‘must’ unilaterally revoke notification, as the initial decision would lack the essential precondition. Similarly, if the basis for the notification disappears, e.g. through another referendum, it appears logical, the AG argues, that the Member State must notify the EU, as the original notification of intention would no longer be in accordance with national constitutional requirements.

Finally, the AG rejects any view that once negotiations have started the EU and the other Member States should have some say because they are invested in the negotiations. He points out that insisting on continued negotiations when the Member State no longer wishes to leave would be tantamount to forcing the Member State out, amounting in kind to an indirect expulsion from the EU. Mere notification and negotiation does not change the State’s status as an EU Member State.


Having determined that unilateral revocation may be possible, the AG outlines three conditions to be satisfied for this course to be taken.

Firstly, there is a formal condition requiring a formal act from the Member State (directed to the European Council). Because notification, to be properly carried out, requires such a formal act, it is logical that revocation thereof requires similar formality.

Secondly, revocation must be in accordance with the State’s constitutional requirements. In the UK context, withdrawal notification required parliamentary consent; such consent would therefore be necessary before the UK could withdraw their Article 50 notification of intention to exit the EU.

Thirdly, there is a temporal limit to unilateral revocation. Once an agreement is formally concluded, notification cannot be revoked because the intention expressed within it has taken full effect.


It was previously suggested numerous times that Article 50 notification is, or should be, unilaterally revocable – for example by Steve Peers – but the opinion of the AG, and the subsequent judgment of the CJEU, confirms that this argument is correct. This outcome may open the door for a last-minute U-turn, allowing MPs not only to accept or reject the withdrawal agreement, but the further possibility of remaining in the EU.

One potential problem – which the Commission and Council have highlighted, and which has been voiced elsewhere  – is that of abusing the possibility of unilateral revocation. Some institutions argue that a Member State might trigger Article 50, spend just under two years attempting to negotiate a better position, and then revoke the notification; only to re-issue it shortly after. Such a possibility might effectively allow the Member State to unilaterally extend the period of negotiation

However, as the AG points out, the possibility for abuse is not generally a reason to deny the mere existence of a right and, given that the Member State must go through national ‘constitutional requirements’ at each step, it is unlikely that allowing unilateral revocation would result in a proliferation of tactical revocations. This is not an argument which is explored by the CJEU, but it provides an additional facet to the argument that denying unilateral revocation would run contrary to the overall logic of the provision itself.

Weatherill calls the idea of treating such a situation as an abuse of law ‘hazy’, proposing that the better solution is to prevent unilateral revocation entirely, as this may also deter the triggering of Article 50 unless the State is ‘absolutely sure’ it wants to risk it. Allowing only negotiated revocation, he argues, would be the better option.

Peers replies convincingly that Weatherill’s position relies on imagined procedural rules which do not exist in the Treaty; on the contrary, the notion of abuse of law does exist in EU law, and could easily be clarified in the event of abuse of Article 50. This appears to be the position adopted by the AG as well.

Perakis has argued that the use of ‘intention’, as relied upon by the AG, should not ‘mislead’, and that focus should instead be placed upon repeated referrals to a ‘decision’. Interpretation here depends upon the weight afforded to each word, and the hierarchy they appear to create. As such it is not obvious whether emphasis should be on the decision to withdraw, or the notification of the intention to withdraw.

It is submitted that one should side with the AG, and the CJEU, on the matter. Additionally, while both Article 50(1) and (2) refer to a decision, it is (2) which details the notification, whose revocation is the subject matter of the case at hand. The ‘decides’ in this context may be equally interpreted as referring to the Member State’s ‘constitutional requirements’ as per Article 50(1), thus it merely refers to this prerequisite for the notification of intention. It therefore does not refer to a final decision to exit the EU. Read as such, ‘intention’ garners greater importance, and the view of the AG that intentions are not definitive is convincing. Both the AG and the CJEU, in this regard, confirm that it is ‘intention’ which bears most weight in this regard, and that intentions are generally not definitive or irrevocable.

What did the CJEU say?

As noted earlier, the CJEU generally follows the AG. Indeed, the purpose of the AG is to provide a legal opinion, without binding the parties. This is evident in the judgment, which references the opinion numerous times, both implicitly and explicitly.  

Although significantly shorter than the opinion with its 76 paragraphs, the judgment largely follows the AG opinion. The CJEU highlights, as did the AG, the importance of the use of ‘intention’ in Article 50, adding that in interpreting a provision of EU law a court must take into account the context, as well as EU law, as a whole.

In this regard, the CJEU also references the sovereignty of Member States, stating that such a status supports the right to revoke notification. Requiring unanimity in the European Council to allow revocation would, the CJEU confirmed, be incompatible with the principle that Member States cannot be forced out of the EU against its will, as argued by the AG.

One slight difference may be found in the conditions for revocation. While the AG considered that this was possible, inter alia, before an agreement is formally concluded, the CJEU held that revocation is possible until an agreement comes into force. In the view of the CJEU, then, mere conclusion of an agreement does not preclude the revocation of withdrawal, provided that it has not yet entered into force. Practically, this will likely make little difference, but it does imply that even if the Withdrawal Agreement is accepted by Parliament, revocation remains possible until it enters into force.

The final answer by the CJEU holds that unilateral revocation is possible before a withdrawal agreement enters into force, or, failing that, until the end of the two-year period, and any extensions thereto, provided it is submitted to the European Council in writing, and is unequivocal and unconditional. The purpose of the revocation should only be to confirm the membership of the State, under terms which are unchanged; this brings the withdrawal procedure to an end.

The case at hand is particularly sensitive, both politically and temporally, and the opinion and judgment is perhaps not what was desired by the EU or the UK.  Additionally, given that the constitutional process which initiated the UK’s exit from the EU was a referendum, it is difficult to see how revocation could be possible without a subsequent referendum. The possibility of a second referendum has previously been discussed for Keep Calm Talk Law, found here.

In no way does this decision imply that a revocation is forthcoming in the case of UK withdrawal from the EU. It does, however, suggest that the door to remain stays open until the very end, reinforcing the position that a Member State exiting the EU is the very last resort.

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Tagged: Brexit, European Union, Parliamentary & Elections

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