R (Miller and Another) v Secretary of State for Exiting the European Union; Re McCord's application

Heard on 5, 6, 7 and 8 December 2016

Lord Neuberger, Lady Hale, Lord Mance, Lord Kerr, Lord Clarke, Lord Wilson, Lord Sumption,

On 1 January 1973, the United Kingdom became a member of the European Economic Community ("the EEC") and certain other associated European organisations. On that date, EEC law took effect as part of the domestic law of the United Kingdom, in accordance with the European Communities Act 1972 which had been passed ten weeks earlier. Over the next 40 years, the EEC expanded from nine to 28 member states, extended its powers or "competences", merged with the associated organisations, and changed its name to the European Community in 1993 and to the European Union in 2009.

In December 2015, the UK Parliament passed the European Union Referendum Act, and the ensuing referendum on 23 June 2016 produced a majority in favour of leaving the European Union. UK government ministers (whom we will call "ministers" or "the UK government") thereafter announced that they would bring UK membership of the European Union to an end. The question before this Court concerns the steps which are required as a matter of UK domestic law before the process of leaving the European Union can be initiated. The particular issue is whether a formal notice of withdrawal can lawfully be given by ministers without prior legislation passed in both Houses of Parliament and assented to by HM The Queen.

It is worth emphasising that nobody has suggested that this is an inappropriate issue for the courts to determine. It is also worth emphasising that this case has nothing to do with issues such as the wisdom of the decision to withdraw from the European Union, the terms of withdrawal, the timetable or arrangements for withdrawal, or the details of any future relationship with the European Union. Those are all political issues which are matters for ministers and Parliament to resolve. They are not issues which are appropriate for resolution by judges, whose duty is to decide issues of law which are brought before them by individuals and entities exercising their rights of access to the courts in a democratic society.

Some of the most important issues of law which judges have to decide concern questions relating to the constitutional arrangements of the United Kingdom. These proceedings raise such issues. As already indicated, this is not because they concern the United Kingdom's membership of the European Union; it is because they concern (i) the extent of ministers' power to effect changes in domestic law through exercise of their prerogative powers at the international level, and (ii) the relationship between the UK government and Parliament on the one hand and the devolved legislatures and administrations of Scotland, Wales and Northern Ireland on the other.

The main issue on this appeal concerns the ability of ministers to bring about changes in domestic law by exercising their powers at the international level, and it arises from two features of the United Kingdom's constitutional arrangements. The first is that ministers generally enjoy a power freely to enter into and to terminate treaties without recourse to Parliament. This prerogative power is said by the Secretary of State for Exiting the European Union to include the right to withdraw from the treaties which govern UK membership of the European Union ("the EU Treaties"). The second feature is that ministers are not normally entitled to exercise any power they might otherwise have if it results in a change in UK domestic law, unless statute, ie an Act of Parliament, so provides. The argument against the Secretary of State is that this principle prevents ministers withdrawing from the EU Treaties, until effectively authorised to do so by a statute.

Most of the devolution issues arise from the contention that the terms on which powers have been statutorily devolved to the administrations of Scotland, Wales and Northern Ireland are such that, unless Parliament provides for such withdrawal by a statute, it would not be possible for formal notice of the United Kingdom's withdrawal from the EU Treaties to be given without first consulting or obtaining the agreement of the devolved legislatures. And, in the case of Northern Ireland, there are certain other arguments of a constitutional nature.

The main issue was raised in proceedings brought by Gina Miller and Deir dos Santos ("the applicants") against the Secretary of State for Exiting the European Union in the Divisional Court of England and Wales. Those proceedings came before Lord Thomas of Cwmgiedd LCJ, Sir Terence Etherton MR and Sales LJ. They ruled against the Secretary of State in a judgment given on 3 November 2016 — R (Miller) v The Secretary of State for Exiting the European Union [2016] EWHC 2768 (Admin). This decision now comes to this Court pursuant to an appeal by the Secretary of State.

The applicants are supported in their opposition to the appeal by a number of people, including (i) a group deriving rights of residence in the UK under EU law on the basis of their relationship with a British national or with a non-British EU national exercising EU Treaty rights to be in the United Kingdom, (ii) a group deriving rights of residence from persons permitted to reside in the UK because of EU rights, including children and carers, (iii) a group mostly of UK citizens residing elsewhere in the European Union, (iv) a group who are mostly non-UK EU nationals residing in the United Kingdom, and (v) the Independent Workers Union of Great Britain. The Secretary of State's case is supported by Lawyers for Britain Ltd, a group of lawyers.

Devolution arguments relating to Northern Ireland were raised in proceedings brought by Steven Agnew and others and by Raymond McCord against the Secretary of State for Exiting the European Union and the Secretary of State for Northern Ireland. Those arguments were rejected by Maguire J in a judgment given in the Northern Ireland High Court on 28 October 2016 — Re McCord, Judicial Review [2016] NIQB 85. On application by the Attorney General for Northern Ireland, Maguire J referred four of the issues in the Agnew case to this court for determination. Following an appeal against Maguire J's decision, the Northern Ireland Court of Appeal has also referred one issue to this Court.

The Attorney General for Northern Ireland supports the Secretaries of State's case that no statute is required before ministers can give notice of withdrawal. In addition, there are interventions on devolution issues by the Lord Advocate on behalf of the Scottish government and the Counsel General for Wales on behalf of the Welsh government; they also rely on the Sewel Convention (as explained in paras 137 to 139 below). They support the argument that a statute is required before ministers can give notice of withdrawal, as do the advocates for Mr McCord and for Mr Agnew.

We are grateful to all the advocates and...