Edwin Coe has produced a summary of the Cases to be presented to the Supreme Court next week with regards to the Article 50 challenge.


Secretary of State for Exiting the European Union


The Queen on the application of (1) Gina Miller (2) Deir Tozetti Dos Santos

Interested Parties    

(1) Graham Pigney and others

(2) AB, KK, PR and children


(1) George Birnie and others

(2) The Lord Advocate

(3) The Counsel General for Wales

(4) The Independent Workers Union of Great Britain


Beginning 5 December 2016, the 11 Supreme Court justices will assess the case as to whether Parliament must approve the triggering of Article 50 and thereby officially set in motion Britain’s exit from the European Union. This case is of huge constitutional importance and arguments will be made by the appellant, two co-respondents, two interested parties and five interveners including representatives from Scotland, Wales and Northern Ireland.

A brief summary of the arguments to be put forward follows:

THE GOVERNMENT (the Appellant)

The main thread of the Government’s argument surrounds the construction of the European Communities Act 1972.  It is their view that, following the result of the referendum, it was the intention of Parliament that the UK’s future in relation to the EU should be decided solely by the Government. This would be achieved by using, they say, the well-established principle of the Royal Prerogative. The Government submit that the onus has to be on the Claimants to highlight where in the ECA 1972 the Royal Prerogative powers were removed. The Government has argued that these prerogative powers have never been removed by the ECA 1972 or some other relevant statute.

Indeed the Government contend that the power to activate Article 50 is a classic example of the proper and well established use of royal prerogative with regard to treaty making and breaking. It is the Government’s case that:

  • The use of the executive power is suitable as it is to be used to give effect to the will of the British people in respect of the wholly democratic referendum result.
  • Parliament has had several opportunities already to restrict the Government’s prerogative powers with regard to the EU exit. The most recent example of this being the recent European Referendum Act 2015.
  • In any event it is “very likely” that any treaty from negotiations with EU members will go to both houses of Parliament for ratification.
  • In regards to the intervention from Scotland, the Government will argue that Holyrood should not be able to wield a veto and foreign affairs, including the signing and repealing of international treaties, is a matter that is reserved to Westminster.

GINA MILLER (first respondent)

Miller’s case proffers that it would be both archaic and unconscionable to allow the Government to take certain actions (such as invoking Article 50) without first securing parliamentary approval.

The submissions of Miller will essentially repeat the points that were successfully put forward at the High Court hearing last month. The salient point being that triggering Article 50 will destroy rights on which only UK parliament can legislate.  An act of Parliament can only be undone by an act of Parliament. Below are the main legal points behind Miller’s case:

  • Triggering Article 50 would destroy rights that were established by UK parliament’s decision to pass the European Communities Act (1972) – rights that only parliament can destroy.
  • The Court has the power and duty to decide questions of law, regardless of whether the judgment pleases politicians or the press (the judges who made the High Court ruling came under attack from various right-wing newspapers and pro-Brexit politicians).
  • The Appellant fails to grasp basic “fundamental principles” of UK law – including parliamentary sovereignty, legality, and the constitutional status of the European Communities Act.
  • The issue of future Brexit legislation, like the Great Repeal Bill, is irrelevant because just the notification of Article 50 will result in statutory rights being destroyed without MPs having a say.

DIER DOS SANTOS (represented by Edwin Coe and the second respondent)

The case on behalf of Mr Santos will also maintain the core arguments that were raised and agreed with by the High Court in “emphatic terms”. The arguments behind Mr Santos’ case focus firmly on the well enshrined principle of Parliamentary Sovereignty:

  • That the use of the royal prerogative would be unconscionable in that it would undermine Parliamentary Sovereignty, a principle that dates back to the Bill of Rights and a fundamental pillar of the UK’s constitution.
  • Further, and in any event, there is no prerogative power to give notification under Article 50.
  • The Government accepts that the UK’s withdrawal from the EU by invoking Article 50 “will undoubtedly lead to the removal of rights and obligations currently conferred or imposed by EU Law.” It is submitted on behalf of Mr Santos that these rights were not granted subject to a condition that they might then be destroyed by the use of a prerogative power.
  • There is nothing in the 1972 Act, any of the subsequent legislation surrounding the EU treaties, in the 2002 Act or in the recent European Referendum Act 2015 that conveys any such Royal Prerogative power to the Government to enable them to invoke Article 50 without Parliamentary approval.
  • A referendum is advisory only and the result is not legally binding – nothing can alter the fact that it is for Parliament to take into account the result of the referendum.

PIGNEY AND OTHERS (first interested party)

Pigney and Others are a group of interested parties who are concerned that their status as EU citizens, and the rights that they enjoy as a result of their citizenship, will be permanently removed through the actions of the Government. Their arguments include the following:

  • That it is no mere general principle but a fundamental feature of our constitution that the executive cannot vary the law of the UK by the use of the prerogative.
  • That through a historical analysis there is no basis for the Court to find that the Government retains any prerogative power to destroy existing rights, in the field of foreign affairs or otherwise.

AB, KK, PR and children (second interested party)

The second interested party represents a large group of people including EU citizens and children residing in the UK who derive their right to do so from EU law that has been implemented into domestic law. They make the points that:

  • The Government cannot lawfully use the royal prerogative to give notification under Article 50 as to do so would fundamentally impact the fundamental rights and interests of children and EEA nationals in that on withdrawal from the EU they will be exposed to potential criminal liability and removal.
  • It is of note that following the result of the referendum there was a 41% increase in racially or religiously aggravated crimes recorded by police in England and Wales.
  • Children did not have a right to vote, or to be heard in the referendum. It is therefore of constitutional importance that their position is considered by Parliament.
  • That the only constitutional and democratically accountable way that these claimants’ interests can be represented is through a proper debate in Parliament and not through the arbitrary exercise of the Royal Prerogative.

George Birnie and others (first intervener)

Known as the Expat Interveners – they are a group of expats who believe that their rights will be undermined through the Government unilaterally invoking Article 50. They argue that:

  • That only Parliament can remove statutory rights which it has itself created.
  • The Government state that the decision has already been made to leave the EU and cannot be turned back on. The Expat Interveners submit that no decision has yet been taken by the Secretary of State to leave the EU. Alternatively, any such decision that has been taken is likely to have been unlawful on traditional public law grounds.
  • The effect of Article 50 notification is to destroy fundamental rights relied upon by the Expat Interveners outside of the jurisdiction of England and Wales.

SCOTLAND (second intervener, represented by the Lord Advocate)

Lawyers for the Scottish Government have been allowed to intervene in the Supreme Court hearing to put forward arguments that are unique to Scotland:

  • The Scottish Government is clear that triggering Article 50 will directly affect devolved interests and rights in Scotland.
  • That triggering Article 50 will inevitably deprive Scottish people and Scottish businesses of rights and freedoms which they currently enjoy.
  • That it simply cannot be right that such fundamental rights of the Scottish people can be removed by the UK Government on the say-so of the executive without parliamentary debate, scrutiny or consent.
  • Any changes to the legislative competence of the Scottish Parliament and/or the executive or legislative competence of the Scottish Government may not be effected by an act of the executive alone.
  • The Sewel Convention dictates that when the UK Parliament will take steps that affect the rights of citizens of Scotland, the consent of the Scottish Parliament should be sought. The rights of citizens will be affected by Brexit and therefore the consent of the Scottish Parliament should be sought before service of the Article 50 Notice.

WALES (third intervener, represented by The Counsel General For Wales)

Representatives from Wales too have been given permission to intervene creating the unprecedented scenario where there is now a legal battle over the role and status of three parliaments. The Welsh believe that Parliament should hold debate before triggering Article 50 and have argued that:

  • Giving notification will modify the competence of the National Assembly for Wales and the Welsh Government. The prerogative power cannot be used to dispense with statutory provisions in this way.
  • Devolution means that the UK is governed by four administrations that are not in a hierarchical relationship. As a result of this, the unilateral triggering of Article 50 by the executive would dispense with parity and mutual respect.
  • A large number of the devolved functions of the Welsh Government derive from EU law – they will be lost upon the UK’s withdrawal from the EU.
  • The Government cannot invoke Article 50 by itself because of the Sewel Convention, a rule introduced at the time of Scottish and Welsh devolution in 1999, which says that both devolved parliaments have to approve any act of Westminster that affects their powers. This argument was also put forward by the Scots and the Independent Workers’ Union.


The Northern Ireland case is referred by the Court of Appeal of Northern Ireland. The Northern Ireland Act 1998 gave effect to the multi-party negotiations concluded by the Belfast Agreement (“Good Friday Agreement”) signed on 10 April 1998. Section 1 NIA deals with the status of Northern Ireland and provides that (1) Northern Ireland shall not cease to be part of the United Kingdom without the consent of the majority of the people of Northern Ireland voting in a poll held for the purposes of this section; (2) but should the majority express a wish in such a poll that Northern Ireland should cease to be part of the United Kingdom and form part of a united Ireland, the Secretary of State will lay proposals before Parliament to give effect to that wish.

The applicant suggests that there can be no change to the constitution of Northern Ireland without the consent of the people of Northern Ireland and that withdrawal from the European Union would constitute such a change.  Thus the consent of the Northern Ireland Assembly is required before service of the Article 50 notice. Further, the Good Friday Agreement has created a substantive legitimate expectation that there would be no change in the constitutional status of Northern Ireland without the consent of the people of Northern Ireland.

The Government of Northern Ireland suggest that the Article 50 Notice does not need either UK Parliamentary approval nor that of the NI Assembly.


The Independent Workers Union, which was set up to represent workers in the so-called gig-economy, has submitted that the Government would be in breach of Scottish constitutional law if it were to trigger Article 50 without the agreement of Parliament at Westminster. Their arguments echo that of the Scottish Government:

  • Leaving the EU involves each part of the UK. The Court must take account of Scotland’s constitutional law and in particular the Claim of Right Act 1689, a stronger piece of legislation than the English Bill of Rights.
  • In Scotland, at least, it is the case that the monarch (and so the Royal Prerogative) is always answerable to Parliament.
  • The Court must also take into account issues, such as the rights of EU migrant workers and trade union members the IWGB represents that would be lost with the UK’s withdrawal from the EU.


Lawyers for Britain have been granted permission to file written submissions although they are not entitled to speak at the hearing. This group, consisting of legal practitioners and academics, supports Brexit, but intervened to “make sure the exit process is carried out in the best interests of the United Kingdom”. Their arguments support the appeal.  They argue that:

  • Even if the European Communities Act 1972 did by implication impose a restriction on the prerogative power of the Crown to withdraw the UK from the EU, the effect of the European Union (Amendment) Act 2008 was to negative any such restriction on the exercise of the wholly new explicit power of withdrawal from the EU under Article 50 of the Treaty on European Union.
  • Parliament must have been aware of the important new power in Article 50 and decided by contrast that its exercise should not be subject to Parliamentary control. The European Union Act 2011 further elaborated the system of Parliamentary control over prerogative acts and thereby further confirmed Parliament’s intention not to fetter the prerogative in the exercise of Article 50.
  • In any event, the effect of the European Union Referendum Act 2015, read against the background of the ECA 1972 and the 2008 and 2011 Acts, was to negate any such restriction which might otherwise have arisen, if the result of the referendum was a majority to leave the European Union.

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