The UK's highest court has ruled that an Act of Parliament is required to give the Government power to give notice under Article 50 beginning the process for leaving the European Union.

The Supreme Court delivered its judgment in Miller v Secretary of State for Exiting the European Union on the morning of 24 January 2017. This was shortly followed by a Government response, delivered by David Davis the Secretary of State for Exiting the EU, in a statement to the House of Commons. Below are a number of short points on what has become a little clearer since the judgment.

What does the Supreme Court judgment say about the process for giving notice under Article 50?

A majority of the Supreme Court Justices (8 to 3; Lords Reed, Carnwath and Hughes dissenting) held that an Act of Parliament is required to give the Government power to give the notice (under Article 50 of the Lisbon Treaty) to the European Union and so begin the procedure for withdrawal from the European Union:

"we [the Supreme Court] consider that, by the [European Communities Act] 1972 Act, Parliament endorsed and gave effect to the United Kingdom’s membership of what is now the European Union under the EU Treaties in a way which is inconsistent with the future exercise by ministers of any prerogative power to withdraw from such Treaties " (paragraph 77 of the judgment).

The Supreme Court Justices held that the essential point is that the Article 50 notice "(…) can only lawfully be carried out with the sanction of primary legislation enacted by the Queen in Parliament." (paragraph 122 of the judgment).

The majority judgment stressed that the form of such legislation is "(…) entirely a matter for Parliament". The judgment is only concerned with the question of the legality of the Government’s proposed use of the prerogative power to give the notice under Article 50. The Supreme Court Justices held that Article 50 notice can only be lawfully given with the sanction of primary legislation enacted by the Queen in Parliament. They held that a resolution of the House of Commons alone, without legislation, would not be sufficient: "only legislation which is embodied in a statute will do" (paragraph 123 of the judgment).

What did the Supreme Court say about the role of the devolved administrations?

The devolved administrations, the Scottish Parliament and Welsh and Northern Ireland Assemblies, do not need to be consulted before Article 50 is triggered, the Supreme Court decided. They have no legal veto on an Act of Parliament authorising the Government to trigger Article 50.

Under the Sewel Convention, the UK Parliament typically seeks the consent of the Scottish Parliament or that of the Northern Ireland or Welsh Assemblies before legislating on devolved matters. One of the questions in the Supreme Court case was whether the convention means that an Act of Parliament authorising the UK’s exit from the EU is contingent on the devolved legislatures’ consent; the Supreme Court Justices unanimously said it was not.

The judgment stressed the fundamental role and importance of constitutional conventions. But it held that these are political conventions and for that reason there is no role for the courts in ensuring their enforcement (paragraph 146 of the judgment).

What did the Supreme Court say about rights of UK residents granted through the EU?

In the proceedings it was accepted as common ground that while Article 50 operates on the plane of international law, because the EU treaties apply as part of UK law, domestic law will change as a result of the UK ceasing to be a party to the treaties: "rights enjoyed by UK residents granted through EU law will be affected" (paragraph 69 of the judgment).  

The Supreme Court noted that many current EU rights fall within the first category (rights capable of replication in UK law) including, "(…) for instance, the rights of UK citizens to the benefit of employment protection such as the Working Time Directive, to equal treatment and to the protection of EU competition law, and the right of non-residents to the benefit of the “four freedoms” (free movement of people, goods and capital, and freedom to provide services)."

The Supreme Court went on to note that some of these rights have already been embodied in UK law by domestic legislation pursuant to section 2(2) of the European Communities Act 1972, and (where incorporated) will not cease to have effect upon the UK's withdrawal from the EU - unless the domestic legislation giving effect to them is repealed in accordance with the law. However, the European Court of Justice will no longer have any binding role in relation to the scope or interpretation of these rights.

The Supreme Court judgment also stated that "Other rights, arising under EU Regulations or directly under the EU Treaties, will cease to have effect upon withdrawal (save in relation to rights and liabilities already accrued), [emphasis added] but many could be replicated in a new statute - eg the proposed Great Repeal Bill.".

The judgment provides no further details, so it is unclear whether this is a reference to what has been referred to as the issue of 'acquired rights'. This goes to the so far unanswered question: whether British citizens and businesses in Europe – and European citizens and businesses in the UK – will be able to rely on any 'acquired rights' either under EU law or general international law in the event that the withdrawal agreement does not cover relevant individual rights, or if the UK left the EU without an agreement at all.

How did the UK Government respond to the judgment?

In delivering the Government's response in the House of Commons on 24 January 2017 David Davis stated that the Government will introduce to Parliament a "straightforward" bill "simply to give power to invoke Article 50 and begin the process of leaving the EU within days" (the Article 50 bill). “This will be a straightforward bill,” said David Davis. “It’s not about whether or not the UK should leave the EU. That decision has already been taken.”

David Davis confirmed that, separate to the Article 50 bill, the 'Great Repeal Bill' will be included in the next Queen's Speech and that it is expected that the draft Great Repeal Bill will be published shortly thereafter. The Government in a Ministerial statement  in October 2016 stated that the Great Repeal Bill will "convert existing EU law into domestic law, wherever practical.".

Will the Government issue a white paper on its negotiating position?

When questioned in the House of Commons on 24 January 2017 House of Commons on 24 January 2017 on whether the Government would publish a white paper setting out the Government's Brexit negotiating priorities, David Davis repeatedly did not confirm that the Government would do so. He referred to Theresa May's speech delivered on 17 January 2017 as "the clearest exposition of a negotiating strategy that I have heard in modern times", 'The government's negotiating objectives for exiting the EU'.

Subsequently, on 25 January 2017, in the course of Prime Minister's Questions Theresa May acknowledged the calls for a white paper and confirmed that the Government will publish a white paper setting out its plans for leaving the EU and give Parliament "every opportunity" to scrutinise her Brexit strategy.

What will happen now?

The effect of the Supreme Court's decision is that the way the Government triggers Article 50 will be subject to Parliamentary scrutiny. The Article 50 bill will need to go through a number of stages in each of the two Houses of Parliament, and Members of Parliament will cast the decisive votes. There will be opportunities for amendments to the Article 50 bill to be proposed in both the House of Commons and the House of Lords. Both Houses will need to agree on the wording of the final Act.

Has the timetable for triggering Article 50 changed?

Despite the need for the Article 50 bill, David Davis in his statement to the House of Commons said that the timetable for invoking Article 50 by the end of March has not changed.

Parliament voted in December 2016 in support of the Government's Brexit implementation timetable. However, in also responding to the judgment the political parties have given more detail on their positions. Labour indicated that it would not seek to frustrate the Article 50 bill, but it would try to amend it. The Liberal Democrats indicated that the party would vote against the Article 50 bill unless the Government agrees to subject the final Brexit deal to a referendum. The Scottish National Party indicated that it too would seek to make amendments.

It is clear that the Government's legal concerns over Brexit do not end with this judgment. Aside from the Article 50 bill now having to pass through both Houses of Parliament and become an Act before the Government can trigger Brexit, it is reported that two new legal challenges are gathering pace.

In Ireland a challenge launched before the Irish High Court at the end of 2016 seeks to clarify if the two year exit process can be terminated at a later date, in other words if notice pursuant to Article 50 is revocable. Whether notice under Article 50 is revocable once given is not a point on which the Supreme Court expressed a view; it was content (at paragraph 26 of the judgment) to assume that "notice under article 50(2) cannot be given in qualified or conditional terms and that, once given, it cannot be withdrawn. It follows from this that once the United Kingdom gives Notice, it will inevitably cease at a later date to be a member of the European Union and a party to the EU Treaties."

Separately, in the High Court at the end of last year, two campaigners, Peter Wilding and Adrian Yalland issued a challenge that the referendum does not grant the Government the authority to take Britain out of the European single market.