The judgment has been made following a referral from the highest Court in Scotland in the case of Wightman v Secretary of State for Exiting the European Union. The case has been seen as a 'David v Goliath' fight with six cross party politicians (including MPs, MSPs and MEPs) using crowdfunding to challenge the Government's interpretation of Article 50.
The question put to the European Court of Justice by the Scottish Court of Session on 21 September 2018 was: "Where, in accordance with Article 50 of the Treaty on European Union, 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 European Union?"
The European Court of Justice heard the case in late November and the opinion of Advocate General Campos Sanchez-Bordona was published on 4 December 2018. The Advocate General reached the conclusion that the UK can unilaterally decide to withdraw the Article 50 notice. Although this was not binding on the Court, the views of the Advocate General are taken into account in the Court's reasoning and have now effectively been officially endorsed.
The Secretary of State for Exiting the European Union had sought to have the action struck out on the basis that the question put to the Court was hypothetical, as withdrawing Article 50 (and remaining in the EU) is not current policy. The European Court of Justice rejected this argument pointing out that the question it had been asked to consider is "precisely the point at issue in the main proceedings". Furthermore the Court noted that two of the petitioning group of politicians are MPs who are being asked to vote upon the ratification of the Withdrawal Agreement on 11th December 2018 and this judgment will assist them to make informed decisions about the potential options available.
The Court considered Articles 65, 67 and 68 of the Vienna Convention on the Law of Treaties 1969, Articles 1, 2 and 50 of the Treaty of the Functioning of the European Union and the European Union (Notification of Withdrawal) Act 2017.
The Court noted that Article 50 does not contain an express rule on revocation but that submitting the notice to withdraw is unilateral in nature, noting that the "decision to withdraw is for that Member State alone to take, in accordance with its constitutional requirements, and therefore depends solely on its sovereign choice".
In line with the Advocate General's opinion, the Court focused on the wording of Article 50(2) that a Member State which decides to withdraw notifies the European Council of its ‘intention’, pointing out that an "intention is, by its nature, neither definitive nor irrevocable".
The Court considered the wider context of European Union membership including the commitment made by Member States to eliminate the barriers which divide Europe and emphasis upon the rights of the citizen. The Court also looked into the drafting of Article 50, where the Member States had expressly agreed on the "voluntary and unilateral nature of the withdrawal decision" and rejected wording which would have allowed the expulsion of a Member State.
In light of this, the Court reached the view that "a State cannot be forced to accede to the European Union against its will, neither can it be forced to withdraw from the European Union against its will". Therefore, during the Article 50 period (ie. before a formal exit has taken place), the UK may give notice in writing to end Brexit, in effect by withdrawing its notice to withdraw. This will be effective provided that the decision to give notice has been reached in line with the UK's constitutional processes (whether this is an Act of Parliament, a fresh referendum or otherwise).
In direct response to the question put forward by the Scottish Court of Session on 21 September 2018 the European Court of Justice states at paragraph 76:
"Article 50 TEU must be interpreted as meaning that, where a Member State has notified the European Council, in accordance with that article, of its intention to withdraw from the European Union, that article allows that Member State — for as long as a withdrawal agreement concluded between that Member State and the European Union has not entered into force or, if no such agreement has been concluded, for as long as the two-year period laid down in Article 50(3) TEU, possibly extended in accordance with that paragraph, has not expired — to revoke that notification unilaterally, in an unequivocal and unconditional manner, by a notice addressed to the European Council in writing, after the Member State concerned has taken the revocation decision in accordance with its constitutional requirements. The purpose of that revocation is to confirm the EU membership of the Member State concerned under terms that are unchanged as regards its status as a Member State, and that revocation brings the withdrawal procedure to an end".
In terms of next steps, the Scottish Court of Session will now take into account the views of the European Court of Justice in deciding the case of Wightman v Secretary of State for Exiting the European Union.
The landmark judgment in Wightman may be expected to encourage those lobbying for the UK to remain as a Member State of the European Union. However although the UK now appears to have a "reverse gear" allowing it to end Brexit without sanction should it wish to do so, this will only be exercised if the UK through its constitutional processes decides to do so. However, given in particular that this is not the current policy of either of the two main political parties within the UK House of Commons, then while it is not impossible such a turn of events would seem most unlikely.