Brexit update: British High Court decision on Article 50 released

4 minute read
03 November 2016



This morning, the British High Court issued its historic decision in R (Miller) v Secretary of State for Exiting the European Union, the Brexit Article 50 case.

The Court found against the government and ruled that Prime Minister May does not have the power to unilaterally trigger Article 50 of the Lisbon Treaty to start the United Kingdom's exit from the European Union, but rather must first secure Parliament's approval to do so. The decision is a significant defeat for the government. The government has announced it will appeal the decision to the Supreme Court.

Read the full text of the official summary of the High Court judgment (PDF).


The case concerns the politically charged question of which branch of the U.K. government has the power to formally start the process of taking the U.K. out of the EU: the executive or Parliament.

In order to start formal Brexit negotiations between the U.K. and the EU, the U.K. must withdraw from the EU in accordance with its own constitutional requirements and, having done so, notify the European Council of its decision - referred to as the giving of Article 50 notice. Once the Article 50 notice is delivered, a two-year period is triggered during which the parties are to negotiate the terms of the U.K.'s withdrawal from the EU.

The claimants, Miller and Santos, challenged the Prime Minister's position that the government can use its royal prerogative powers to trigger Article 50 without Parliamentary approval. The claimants argued that only Parliament can make the decision to leave and authorize delivery of the Article 50 notice. This is because the prerogative powers are not available to the government where their use would contravene the will of Parliament as expressed by statute. In this case, the European Communities Act 1972, passed by Parliament, which gave effect to EU laws in the U.K., will be frustrated if the U.K. withdraws from the EU and EU law ceases to apply in the country. For that reason, the claimants argued that the U.K.'s constitutional requirements are that the decision to give the Article 50 notice must be made by Parliament.


The opponents of Brexit supported the claimants, believing that there is a possibility that Parliament might not approve giving Article 50 notice or, if approved, may attach conditions to doing so, e.g., scrutiny of the negotiations as they progress. In polls taken prior to the Brexit vote on June 23, a majority of MPs indicated that they supported the U.K. remaining in the EU.

Before today's decision, the Prime Minister had indicated her intention to issue the Article 50 notice before the end of March 2017. The view has been expressed by many that this timetable is unwise as important elections will be held in both France and Germany in 2017, which may distract the two most important EU countries to the Brexit negotiations, or see the negotiations become the subject of electioneering. If the High Court's decision stands, the requirement for Parliamentary approval may push back the date for triggering Article 50 to late 2017.

Next steps

The Supreme Court has already set aside December 7 and 8 to hear the government's appeal of the High Court's decision.

Please consult our Brexit Untangled site later today for a full analysis of this historic decision.

Should you have any questions, your Gowling WLG client relationship partner is available at any time to assist in the assessment of the potential impact of Brexit on your business and to link you to specific support from our Brexit Unit.

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