Article 50 notification: High Court rules that parliamentary approval is required for the UK to withdraw from the EU

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On 3 November 2016, the High Court ruled in R (on application of Miller) v Secretary State for Exiting the European Union [2016] EWHC 2768 (Admin) that Article 50 cannot be invoked without parliamentary approval.

The process for departure from the EU is set out in Article 50 of the Treaty on the Functioning of the European Union.  This provides that a Member State may decide to withdraw from the EU in accordance with its own constitutional requirements.  Once that decision has been made, the withdrawal process is initiated by the Member State giving notice to the European Council of its intention to withdraw.  Withdrawal actually occurs on the date of entry into force of a withdrawal agreement between the EU and the (former) Member State, or failing that, two years after the notification unless the European Council (i.e. the Member States) and the withdrawing state decide unanimously to extend the period.

Miller concerned the UK’s constitutional requirements for making the decision to withdraw from the EU and, as a result, what authorisation the Government needs before it can give notice.  The Government argued that it is entitled to use its prerogative powers to trigger Article 50.  Prerogative powers are a body of discretionary powers held by the Crown and exercised by the Government in carrying out executive functions.  The exercise of prerogative powers does not require prior parliamentary approval.  In contrast, the claimants argued that the Government could not use its prerogative powers to act on behalf of the Crown to exercise Article 50 and needed the authorisation of Parliament to do so.

The High Court’s ruling

The High Court unanimously decided in favour of the claimants and against the Government. The key aspects of the judgment are:

  • The High Court emphasised the significance of constitutional principles in play. In particular, the sovereignty of Parliament and secondly that the Crown has no power to alter the law of the land by using the royal prerogative.
  • The High Court emphasised that these strong constitutional principles drive the interpretation of constitutional legislation, including the European Communities Act 1972 (“ECA”) which gives effect to EU rights and obligations in domestic UK law.
  • It was agreed by both sides that the ultimate consequence of exercising Article 50 will be the removal of domestic UK rights created by virtue of the ECA. However, the Government contended, essentially, that the effect of the ECA was subject to whether the UK was bound by the EU treaties, which itself was an issue where the royal prerogative was in play.  It claimed that the ECA had not removed its right to use the royal prerogative to withdraw from the EU treaties.  The claimants, on the other hand, argued that the royal prerogative is limited to international affairs, and withdrawal from the EU affected domestic rights.
  • The High Court held that the strength of the underlying constitutional principles was such that the intention of Parliament in enacting the ECA must be considered to have been not to allow the Government to use the royal prerogative to undo or override EU-derived rights in domestic UK law. Indeed, the High Court held that it should be strongly inferred that Parliament intended to remove such power.

The High Court therefore concluded that there is no power for the Government to use the royal prerogative to exercise Article 50.

In addition, the High Court stressed that its judgment addressed a pure question of law, as to the process for exercise of Article 50, rather than a political issue on the merits of leaving the EU.

Appeal to the Supreme Court

On 8 November 2016, the Supreme Court granted the Government permission to appeal against the judgment of the High Court.  Given the constitutional importance of this case and the Prime Minister’s announcement that Article 50 will be triggered by the end of March 2017, the appeal will be heard between 5-8 December 2016 by the Supreme Court and leapfrogging the Court of Appeal, which is the usual venue for High Court appeals. The judgment is expected in the New Year.