Brexit: European Court of Justice ruling on the Article 50 process

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The Wightman case was brought by a cross-party group of Scottish politicians, backed by the Good Law Project. The petitioners wished to get legal certainty over whether an EU Member State which had triggered Article 50 of the Treaty on European Union (TEU) by giving notice of its intention to leave could unilaterally revoke that notice and decide to stay in the EU. On 10 December 2018, the Court of Justice of the European Union (CJEU) issued its judgement on Wightman, ruling that the UK is free to unilaterally revoke the Article 50 notification of its intention to leave the EU.

How did the ruling come about?

 On 19 December 2017, a cross-party group of Scottish politicians lodged a petition for judicial review at the Court of Session in Edinburgh to determine whether the UK could unilaterally revoke its Article 50 notification before the expiry of the two-year negotiation period. The petitioners in the case are:

  • Andy Wightman MSP (Scottish Greens)
  • Ross Greer MSP (Scottish Greens)
  • Joanna Cherry QC MP (SNP)
  • Alyn Smith MEP (SNP)
  • David Martin MEP (Scottish Labour)
  • Catherine Stihler MEP (Scottish Labour)
  • Jolyon Maugham QC (Good Law Project)

They were joined in May 2018 by Chris Leslie MP (Labour) and Tom Brake MP (Liberal Democrats).

The CJEU is the only court permitted to offer a binding interpretation of EU law. Since Article 50 of the TEU is a provision of EU law, the petitioners argued that the issue should be referred to the CJEU for advice. The original application for judicial review was granted in March 2018. On 8 June, the Court declined to refer the matter to the CJEU, ruling that the question was hypothetical as the UK Government does not intend to withdraw the Article 50 notification.

Following an appeal to the Inner House of the Court of Session, this decision was reversed, with the Court considering that an answer from the CJEU would clarify the options open to MPs in relation to any forthcoming parliamentary vote concerning the UK’s withdrawal from the EU. The UK Government sought to appeal against the ruling, but its request for an appeal was rejected by the Supreme Court on 20 November.

On 3 October, the Court of Session formally referred the issue to the CJEU for a preliminary ruling. Mindful that ratification of a withdrawal agreement, and any framework on the future relationship between the UK and the EU, requires the approval of the UK Parliament, the Court requested that the CJEU provide its ruling more quickly than usual by using the expedited procedure. This request was granted, ensuring that the case was given priority.

What does the ruling say?

An initial legal opinion was provided by one of the CJEU’s Advocates General on 4 December 2018. In that opinion, AG Campos Sánchez-Bordona, suggested that a Member State could unilaterally revoke Article 50 “provided that the revocation has been decided upon in accordance with the Member State’s constitutional requirements, is formally notified to the European Council and does not involve an abusive practice.”

Whilst the CJEU is under no obligation to follow an AG’s opinion when making its final judgement, on 10 December 2018, the Full Court ruled that a Member State is free to unilaterally revoke an Article 50 notification. Its detailed findings were summarised in a press release issued at the same time:

  • When a Member State has notified the European Council to withdraw from the European Union, as the UK has done, that Member State is free to revoke unilaterally that notification.
  • That possibility exists for as long as a withdrawal agreement concluded between the EU and that Member State has not entered into force or, if no such agreement has been concluded, for as long as the two-year period from the date of the notification of the intention to withdraw from the EU, and possibly any extension, has not expired.
  • The revocation must be decided following a democratic process in accordance with national constitutional requirements. This unequivocal and unconditional decision must be communicated in writing to the European Council.
  • Such a revocation confirms the EU membership of the Member State concerned under terms that are unchanged as regards its status as a Member State and brings the withdrawal procedure to an end.

The CJEU rejected the UK Government’s argument that, because the UK does not intend to revoke its Article 50 notice, the question before the court was hypothetical and did not require an answer. Instead, the Court emphasised that some of the petitioners are MPs, who must vote on the ratification of the Withdrawal Agreement, and that its ruling will “clarify the options open to them in exercising their parliamentary mandates”.

The CJEU also rejected the argument from the Council of the EU and the European Commission that the UK could only take back its Article 50 notification with the unanimous consent of the European Council (i.e. every other EU Member State would have to agree before the UK could revoke its Article 50 notice). The Court judged that this would be inconsistent with the EU’s commitment to the values of liberty and democracy, along with ever closer union among the peoples of Europe, as it could lead to a Member State essentially being forced to leave the EU against its will.


In addition to confirming the UK’s right to unilateral revocation, the ruling also raises several key issues:

  • Any decision to revoke the Article 50 notification could only be taken after a democratic process in line with the UK’s own constitutional requirements. The nature of these requirements would be for the UK itself to determine and would be a matter of UK law, not EU law. What this would actually look like is not immediately clear – some legal experts have argued that an Act of Parliament would be necessary, while others are less sure. Any disagreement about whether legislation was required might be a question for the UK courts and, ultimately, the UK Supreme Court.
  • Any decision to revoke the Article 50 notification must be “unequivocal and unconditional” – i.e. the goal of revocation must be to actually stay in the EU, not simply alter the shape or direction of withdrawal negotiations.
  • Deciding to stay in the EU will not result in changed terms of membership. The suggestion has been made by some EU officials that such a decision could result in the end of UK-specific membership terms, such as the rebate and the opt-outs from Schengen and the Euro. The ruling takes that possibility of the table.

On 10 December, the Secretary of State for Exiting the EU, Stephen Barclay MP, gave a statement to the House of Commons in which he accepted the judgement of the CJEU, but stressed that this did not alter UK Government policy, which is that the Article 50 notice will not be revoked.

What happens next?

Now that the CJEU has provided a ruling on the relevant aspects of EU law, the case reverts back to the Court of Session for further consideration and a final judgement, with a hearing scheduled for 20 December.


Andrew Warden, SPICe Research