Miller v Secretary of State for Exiting the European Union

Miller v Secretary of State for Exiting the European Union
Case name	Miller v Secretary of State for Exiting the European Union
Court	Supreme Court of the United Kingdom
Citation	[2017] UKSC 5
Date decided	24 January 2017
Judges	Lord Neuberger, Lord Mance, Lord Kerr, Lord Wilson, Lord Reed, Lady Hale, Lord Carnwath, Lord Hughes, Lord Hodge
Prior actions	High Court (Divisional Court) [2016] EWHC 2768 (Admin)

Miller v Secretary of State for Exiting the European Union was a landmark United Kingdom constitutional law case concerning the domestic legal process required to give effect to the result of the 2016 EU referendum and to initiate withdrawal under Article 50 of the TEU. The case raised questions about the respective roles of the Parliament, the Prime Minister, the Crown and the Supreme Court in relation to rights protected by domestic legislation and the operation of EU law within the UK legal order.

Background

The claimant, an individual campaigner associated with Gina Miller (note: proper nouns only), challenged the government's assertion that the royal prerogative could be used by the Secretary of State to trigger Article 50 TEU without prior legislative approval from the House of Commons and the House of Lords. The challenge followed the 2016 referendum result, in which the Vote Leave campaign and the Leave.EU campaign competed with the Remain campaign and figures such as David Cameron and Theresa May featured in public debate. The government's position drew on historical practice involving prerogative powers exercised in relation to foreign affairs and treaties, notably cases such as see main case in the longer jurisprudential lineage.

Legal issues

The litigation focused on several issues: whether rights created by the European Communities Act 1972 and preserved by domestic statutes could be removed by executive action under the prerogative; whether triggering Article 50 TEU was an exercise of prerogative power subject to judicial review; and whether the Sewel Convention and the role of the Devolved legislatures (the Scottish Parliament, the Welsh Parliament and the Northern Ireland Assembly) required legislative consent. Claimants invoked principles from precedent such as Miller's doctrinal antecedents and judgments in cases like R (Jackson) v Attorney General and Entick v Carrington to argue for parliamentary sovereignty and legal safeguards for statutory rights such as those under the Human Rights Act 1998 and rights derived from EU law including the four freedoms and the Charter.

High Court proceedings

The case was heard in the High Court (Divisional Court) with significant oral submissions from counsel representing the claimants and the Secretary of State for Exiting the European Union along with interveners including the Scottish Government, the Welsh Government, the Northern Ireland Executive and various civil society organisations. The Divisional Court considered statutory interpretation of the European Communities Act 1972 and the extent of prerogative power in international relations, drawing on precedents like R v Secretary of State for the Home Department, ex parte Fire Brigades Union and procedural rules under the Constitutional Reform Act 2005. The High Court delivered a judgment requiring parliamentary authorization for triggering Article 50, a ruling that the government appealed to the Supreme Court.

Supreme Court judgment

The Supreme Court, sitting with a panel of eleven Justices, held by a majority that the Crown did not have power under the prerogative to alter domestic law rights created by Parliament without explicit statutory authority and that an act to trigger Article 50 TEU would inevitably affect rights under the European Communities Act 1972. The Court referenced constitutional principles including parliamentary sovereignty, the rule of law as articulated in decisions such as R (Jackson) v Attorney General and the protection of rights in statutes like the European Communities Act 1972 and the Human Rights Act 1998. The judgment required the government to obtain an Act of Parliament to authorise the notice under Article 50, thereby affirming the centrality of Parliament in authorising major constitutional changes. Separate opinions by Justices including Lord Neuberger, Lady Hale, and Lord Reed addressed the interplay between prerogative powers, statutory rights, and conventions such as the Sewel Convention and their justiciability.

Political and constitutional impact

The decision had immediate political consequences for the May government and the timetable for UK withdrawal, prompting the introduction of primary legislation – the European Union (Notification of Withdrawal) Act 2017 – to authorise the Prime Minister to notify the European Council under Article 50 TEU. The judgment intensified public debate involving actors such as Boris Johnson, Jeremy Corbyn, and devolved leaders including Nicola Sturgeon and stimulated discussion in the House of Commons and the House of Lords about sovereignty, parliamentary oversight, and ministerial accountability. The ruling also influenced constitutional scholarship and commentary in outlets discussing the balance between prerogative powers, the sovereignty of Parliament and the rights enshrined by statutes like the European Communities Act 1972.

Subsequent developments and related litigation

Following the judgment, Parliament passed the European Union (Notification of Withdrawal) Act 2017, enabling the Prime Minister to serve notice under Article 50. Subsequent litigation engaged the Supreme Court and the European Court of Justice on matters such as the unilateral revocability of Article 50 notifications and the legal status of withdrawal agreements, with cases including disputes brought by regional governments and litigants in the Gibraltar jurisdiction. The case's legacy persisted in later constitutional challenges involving the Withdrawal Agreement Act 2020 and litigation concerning the Northern Ireland Protocol before courts in the United Kingdom, the Court of Justice of the European Union, and domestic appellate courts.

Category:United Kingdom constitutional case law