Article 50 appeal to the Supreme Court

The UK’s Supreme Court, comprising the country’s 11 most senior judges, has now heard the Government’s appeal against the judgment of the High Court…

R (on the application of Miller and Dos Santos) v Secretary of State for Exiting the European Union and associated references

The UK’s Supreme Court, comprising the country’s 11 most senior judges, has now heard the Government’s appeal against the judgment of the High Court of 3 November 2016 in the case of R (on the application of Santos & Miller) v Secretary of State for Exiting the European Union.

What is the case about?

As noted in our Legal Update circulated on 27 October 2016, the central issue is whether a prerogative power can be used by the Government to give formal notice of the UK’s intention to withdraw from the European Union (“EU”) under Article 50 of the Treaty on European Union.

The High Court judgment

Significant time was spent in the High Court considering important constitutional issues relating to the Government’s ability to use prerogative powers to remove rights of individuals that had been conferred by an Act of Parliament, in this case the European Communities Act 1972 (“ECA 1972”).

The Claimants submitted that the creation or removal of such rights must be reserved to Parliament.

Against this, the Government argued that Article 50 notification to withdraw from the EU Treaties would not, of itself, affect individuals’ rights and obligations.  The EU Treaties created rights and obligations at an international level and these were given domestic status by UK Acts of Parliament.  In passing the ECA 1972, Parliament had vested in UK citizens rights under EU law as it changed from time to time, and in repealing the ECA 1972 Parliament would remove these rights.

The High Court agreed with the Claimants, and the Government appealed to the Supreme Court.

Supreme Court hearing

Each party maintained the arguments that it had presented in the High Court.

For the Government:

  • It can trigger Article 50 by the use of a prerogative power and a parliamentary vote is unnecessary.  Ministers may make and unmake treaties by exercise of prerogative power in the international arena, and withdrawing from the EU Treaties would itself have no effect on statutory rights in domestic law.
  • Parliamentary sovereignty over domestic law would be maintained.

For the Respondents:

  • Parliament is sovereign and the Government cannot use its “Executive” powers to override rights enshrined in domestic law by statute.  The ECA 1972, they argued, was the vehicle for the UK’s accession to the EU and therefore legislation must be passed to facilitate our exit; and
  • Prerogative powers cannot be used to nullify a statutory scheme.

Scotland and Wales were granted permission to intervene in the Supreme Court hearing in their capacity as devolved Parliaments.  Heavy reliance was placed on the Sewel Convention which provides that the UK Parliament may not legislate on devolved matters without the consent of the devolved Parliaments.  Both interveners argued that a Parliamentary vote would be required to trigger Article 50.

During day three of the hearing, 7 December 2016, the House of Commons passed a motion backing the Government’s proposed Article 50 timetable.  At Lord Neuberger’s prompting, it was acknowledged by James Eadie QC, for the Government, that the Commons vote did not change the law and would not authorise the Government to trigger Article 50 should it fail in its appeal before the Supreme Court.


If the Supreme Court decides that Parliament must approve the giving of notice under Article 50, this is likely to thwart the Prime Minister’s plan to commence the Brexit process by the end of March 2017, notwithstanding the House of Commons’ vote on 7 December 2016.

In theory, based on the Government’s statement that it will produce a one line Bill if its appeal is unsuccessful and the stated intent of Parliament to uphold the referendum result, it is possible that Parliament may quickly pass an Act of Parliament empowering the Government to trigger Article 50 by that deadline.

In practice, it is perhaps more likely that Parliament will take that opportunity to debate the principles on which the Government will negotiate the UK’s departure, which would in turn cause delay.

Judgment is expected to be handed down by the Supreme Court in January 2017.

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