HM Insights

Is Brexit inevitable, or can the UK still withdraw its withdrawal?

Reference to be made to the Court of Justice of the EU

Britain is hurtling towards an EU exit on 29 March 2019 but is Brexit inevitable, or can the UK still withdraw its withdrawal? The Inner House of the Court of Session has agreed that we should ask the Court of Justice of the EU (CJEU) to confirm.

Brexit Commercial Contracts Scotland


A Court of Session action was brought by petitioners, including members of the Scottish, UK and European Parliaments, in December 2017. The petition for judicial review has evolved significantly since that date and the resulting application to the court is for declarator specifying: “whether, when and how" the UK's notification of withdrawal from the EU under Article 50 "can unilaterally be revoked". At first instance, Lord Boyd deemed the question to be hypothetical and, in any event, outwith the court's jurisdiction as an encroachment on parliamentary sovereignty. Accordingly, he refused to make a referral to the CJEU for a preliminary ruling under Article 267 of the Treaty on the Functioning of the EU in June 2018. His decision has now been overturned unanimously on appeal.

The issue

Article 50 does not explicitly say whether or not the process can be halted. The legal question is therefore whether the Article 50 notification of withdrawal can be unilaterally revoked before the expiry of the two year period; with the effect that the UK would remain in the EU. If the notification is revocable, what conditions apply? The petitioners maintain that the answers to these questions can only be given by the CJEU. They therefore seek a reference to the CJEU for a preliminary ruling.

The opinion

The Lord President, Lord Carloway, noted that references by the Scottish courts to the CJEU have been rare with only about ten references having been made in the past 45 years. Nevertheless, he considered that it is justified in this case (and likely to be accepted by the CJEU) because:

"The situation is not hypothetical or academic. Notification of withdrawal has been made. It may, in the absence of supervening events and perhaps in any event, take effect in about six months time. The court has been asked the question of “whether, when and how the notification ... can unilaterally be revoked” in advance of the expiry of the two year period. This can only be answered definitively by the CJEU. An answer would require to be provided before this court could grant the appropriate declarator. In these circumstances, reference to the CJEU for a preliminary ruling under Article 267 of the TFEU is “necessary”."

The three judgments contain interesting commentary on parliamentary privilege and the operation of the separation of powers between the judiciary and the legislature so are worth reading in full.

The preliminary ruling

The question to be posed to the CJEU is:

Where, in accordance with Article 50 of the TEU, a Member State has notified the European Council of its intention to withdraw from the European Union, does EU law permit that notice to be revoked unilaterally by the notifying Member State; and, if so, subject to what conditions and with what effect relative to the Member State remaining within the EU”.


It is impossible to second guess the outcome of a CJEU preliminary ruling in response to this question (which does not stop people from trying) but it is important to bear in mind that the decision will be a legal interpretation of Article 50, not a political determination of whether or not it is appropriate for the UK to reverse its decision to leave.

Many lawyers have concluded that the UK's decision to leave became irreversible as soon as Article 50 was triggered on 29 March 2017. This was certainly the Prime Minister's stated intention and both sides in the Supreme Court case (R (Miller) v Secretary of State for Exiting the European Union) assumed that Article 50 was irrevocable. However, the author of Article 50, Lord Kerr of Kinlochard, is reported to have told the BBC that the UK could choose to stay in the EU even after exit negotiations had begun.

The request for a preliminary ruling has now been referred under the CJEU's expedited procedure in Article 105.1 of the Rules of Procedure and will be heard in Luxembourg on 27 November 2018. A decision is expected before the end of the year, to take account of the timescales for a vote in the Westminster parliament on the terms of leaving the EU.

Harper Macleod partner Jennifer Jack is part of a team of leading Scottish and English lawyers, which also includes Morag Ross QC (Axiom Advocates), Gerry Facenna QC and Anneli Howard (both Monckton Chambers) and solicitor John Halford (Bindmans LLP, London), representing two Westminster MPs in this high profile case: Tim Brake, the Liberal Democrat spokesperson on Brexit and Chris Leslie, a prominent Labour backbencher. Jennifer has emphasised "the importance of this case in terms of obtaining guidance from the courts on important issues of parliamentary sovereignty and rule of law in the context of the constitutional future of this country".

The full text of the decision can be accessed here.