Miller & Anor, R (On the Application Of) v The Secretary of State for Exiting the European Union (Rev 1)

The question for the court

On 1 January 1973 the United Kingdom joined the European Communities* This occurred as a result of a process of Treaty negotiation by the government, the enactment of the European Communities Act 1972 ("the ECA 1 972") to give effect to Community law in the national legal systems of the United Kingdom and then ratification by the United Kingdom and other Member States of the amended Community Treaties. Thus, as a result of the ECA 1972, Parliament by primary legislation gave effect in each jurisdiction of the United Kingdom 10 bifidivyg obligations and rights arising under those Treaties. In due course the European Communities became the European Union.

On 23 June 2016 a referendum took place under the European Union Referendum Act

Withdrawal from the European Union under the Treaty provisions of the European Union is governed by Article 50 of the Treaty on European Union ("TEU"). That Article came into force in 2()()9 after amendment of the TEU by the Lisbon Treaty of 2007*

The common ground that the question is justiciable

The parties to the proceedings to resolve the legal question

The scheme of the judgment

Article 50 of the TEU

The terms ofArticle 50

Article 50 states:

Common ground: notice is irrevocable and cannot be conditional

The effect of the notice

A withdrawal agreement under Article 5(), if one is made, may preserve some parts of the relevant Treaties or may make completely new provision for various matters, Since the Crown will negotiate the terms of any withdrawal agreement, this means that the Crown is entitled to pick and choose which existing EU rights, if any, to preserve - if it can persuade the European Council to agree and which to remove, Again, therefore, the effect of the Article 5() negotiation process on relevant rights is direct.

The Secretary of State was at pains to emphasise that, if a withdrawal agreement is made, it is very likely to be a treaty requiring ratification and as such would have to be submitted for review by Parliament, acting separately, under the negative resolution procedure set out in section 2() of the Constitutional Reform and Governance Act 2010 ("the CRAG 2010"). The procedure under section 20 does not involve the enactment of primary legislation. For this reason, the claimants do not accept that the Secretary of State's reliance on the CRAG 2010 meets their submission.

Moreover, if by virtue of the operation of the procedure under section 2() a decision were taken that a withdrawal agreement should not be ratified, meaning that it did not come into effect as an agreement, the effect would be that the basic two year period would continue to run under Article 5()(3) so that the EU Treaties would cease to apply to the United Kingdom at the expiry of that period (or any agreed extension)e Parliament's consideration of any withdrawal agreement under the procedure in the CRAG 2010 would thus be constrained by the knowledge that if it did not approve ratification of it, however inadequate it might believe the withdrawal agreement to be, the alternative would likely eventually to be complete removal of all rights for the United Kingdom and British citizens under the EU Treaties when the relevant Article 50 time period expires,

Is the challenge by the claimants a challenge to the decision to withdraw or giving o] the notice?

In our view, nothing really turns on this, since it is clear that the two provisions have to be read together. The notification under Article 5()(2) is of a decision under Article If the Crown has no prerogative power under the constitutional law of the United Kingdom to give a notice under Article 50(2). then it would appear to follow that under the provisions of Article 50(1) it cannot, on behalf of the United Kingdom, acting solely under its prerogative powers, make a decision to withdraw "in accordance with [the United Kingdom's] own constitutional requirements

The principles of constitutional law: the sovereignty of Parliament and the prerogative powers of the Crown

The United Kingdom constitution

The United Kingdom does not have a constitution to be found entirely in a Mitten document. This does not mean there is an absence of a constitution or constilutional law. On the contrary, the United Kingdom has its own form of constitutional law, as recognised in each of the jurisdictions of the four constituent nations, Some of it is written, in the form of statutes which have particular constitutional importance (as we explain at paragraphs 43-44). Some of it is reflected in fundamental rules of law recognised by both Parliament and the courts. There are established and wellrecognised legal rules which govern the exercise of public power and which distribute decision-making authority between different entities in the state and define the extent of their respective powers. The United Kingdom is a constitutional democracy framed by legal rules and subject to the rule of law. The courts have a constitutional duty fundamental to the rule of law in a democratic state to enforce rules of constitutional law in the same way as the courts enforce other laws.

In these proceedings, this court is called upon to apply the constitutional law of the United Kingdom to determine whether the Crown has prerogative powers to give notice under Article 50 to trigger the process for withdrawal from the European Union. The law we were taken to was primarily the law of England and Wales, with some reference to the position in the other jurisdictions in the United Kingdom, Scotland and Northern Ireland. Although this court only has jurisdiction to apply the law of England and Wales, we note that no-one in these proceedings has suggested that such parts of constitutional law in Scotland and Northern Ireland in relation to the interaction between statute and the Crown's prerogative powers as are relevant to determine the outcome in this case are any different from the law of England and Wales on that topic. Accordingly, for ease of reference and in view of the general constitutional importance of this case we will refer to UK constitutional law

The sovereignty of the United Kingdom Parliament

It is common ground that the most fundamental rule of UK constitutional law is that the Crown in Parliament is sovereign and that legislation enacted by the Crown with the consent of both Houses of Parliament is supreme (we will use the lhmiliar shorthand and refer simply to Parliament). Parliament can, by enactment of primarv legislation. change the law of the land in any way it chooses* There is no superior form of law than primary legislation, save only where Parliament has itself made provision to allow that to happen, The ECA 1972, which confers precedence on EU law, is the sole example of this,

But even then Parliament remains sovereign and supreme, and has continuing power to remove the authority given to other law by earlier primary legislation- Put shortly, Parliament has power to repeal the ECA 1972 if it wishes.

In what is still the leading account, An Introduction to the Law of the Constitution by the constitutional jurist Professor A. V. Dicey, he explains that the principle of Parliamentary sovereignty means that Parliament has:

The principle of Parliamentary sovereignty has been recognised many times in leading cases of the highest authoritys Since the principle is common ground in these proceedings it is only necessary to cite the speech of Lord Bingham of Cornhill in R (Jackson) vAttorney General [20051 UKHL 56; [2006] 'l AC 262 at [91:

The Crown 's prerogative powers

The extent of the powers of the Crown under its prerogative (often called the roval prerogative) are delineated by UK constitutional law. These prerogative powers constitute the residue of legal authority left in the hands of the Crown. As Lord Reid said in Burmah Oil Co (Burma Trading) Ltd v Lord Advocate [1965] AC 75, at 1()1

An important aspect of the fundamental principle of Parliamentary sovereignty is that primary legislation is not subject to displacement by the Crown through the exercise of its prerogative powers, But the constitutional limits on the prerogative powers of the Crown are more extensive than this, The Crown has only those prerogative powers recognised by the common law and their exercise only produces legal effects within boundaries so recognised. Outside those boundaries the Crown has no power to alter the law of the land. whether it be common law or contained in legislation,

This subordination of the Crown (i.e. the executive government) to law is the foundation of the rule of law in the United Kingdoms It has its roots well before the

Sir Edward Coke reports the considered view of himself and the senior judges of the time in The Case of Proclamations (161()) 12 Co. Repe 74, that:

The position was confirmed in the first two parts of section I of the Bill of Rights 1688:

The legal position was summarised by the Privy Council in The Zamora [1916] 2 AC 77, at 90:

As we shall explain in more detail in examining the submission of the Secretary of State (see paragraphs 77 and following), it is the Secretary of State's case that nothing

The effect of Treaties on the domestic law of the United Kingdom

The general rule that the conduct of international relations, including the making and unmaking of treaties, is a matter for the Crown in exercise of its prerogative powers arises in the context of the basic constitutional principle to which we have referred at paragraph 25 above, that the Crown cannot change domestic law by any exercise of its prerogative powers. The Crown's prerogative power to conduct international relations is regarded as wide and as being outside the purview of the courts precisely because the Crown cannot, in ordinary circumstances, alter domestic law by using such power to make or unmake a treaty. By making and unmaking treaties the Crown creates legal effects on the plane of international law, but in doing so it does not and cannot change domestic law. It cannot without the intervention of Parliament confer rights on individuals or deprive individuals of rights.

The general position was explained by Lord Oliver of Aylmerton giving the leading speech in the Tin Council case, LHS Rayner (Mincing Lane) Ltd v Department of Trade and Industry [1990] 2 AC 418, at 499E500D as follows:

The relevance of the principles to the question in the case

At the same time, it is this feature which leads the Secretary of State to contend that the Crowrfs prerogative power to give notice to withdraw from the ^PI"EU and the other treaties has not been removed by primary legislation* Hence, it is argued, Parliament must be taken to have recognised that the Crown would have power to give notice under Article 50 in the exercise of its prerogative to conduct 'international relations on the part of the United Kingdom and thereby intended that the Crown should have power to bring about the changes in domestic law about which the claimants complain.

The domestic efTect of EU law and the ECA 1972

The forms of EU law and the role of the Court ofJustice of the European Union

As again the basic picture about how EU law operates is common ground, it is not necessary to give more than a brief explanation. Put very shortly, thereforet EU law as contained in the relevant Treaties in some parts contains rights for individuals and in other parts creates law-making institutions which can legislate to make new legally binding norms of EU law from time to time. The principal forms of EU legislation are (l) Directives, which require Member States to introduce changes into their national law in conformity with what is set out in them, and (2) Regulations, which have direct effect in the national law of Member States. Where the Treaties create rights 'for individuals, those rights may be enforced as directly effective in the national courts of Member States. The same is true of rights set out in Regulations, Also, some individual rights set out in Directives are directly effective and may be relied upon in the national courts of Member States.

These directly effective rights under EU law override even domestic primary legislation. Thus, for so long as EU law is accepted and applied by the national courts of a Member State, it operates as a form of law which is in that sense superior to all domestic law.

The Community and EU Treaties created the European Court of Justice (now the Court of Justice of the European Union — "CJEU") as the judicial body with authority to interpret and rule upon EU laws The CJEU does so both in proceedings brought bv Member States or by EU institutions and in cases referred to it by national courts under the reference procedure now contained in Article 267 of the Treaty on the Functioning of the European Union ("TFEU"). Controversial issues of EU law are to be referred by national courts to the CJEU for authoritative determination bv that Court. and national courts are obliged to apply EU law as interpreted by the CJEU

These basic features of Community law were established well before the United Kingdom joined the European Communities in 1973. In particular, the superiority of EU law with direct effect was established in the well-known judgments of the Court of Justice in Case 26/62, Van Gend & Loos and case costa v ENEL [1964] ECR 585- It has been affirmed many times since, for instance in the well-known judgment in Case 106/77, Amminstrazione delle Finanze v Simmenthal SpA Where EU law does not have direct effect but domestic legislation is introduced by a Member State to comply with its obligations under a Directive or other EU law. then as a matter of EU law a strong interpretive obligation applies so that the domestic legislation must be interpreted so as to be compatible with EU law wherever possible: Case C-106/89- Marleasing

As a practical matter, by reason of the limits on its prerogative powers referred to at paragraph 25 above, the Crown could not have ratified the accession of the United Kingdom to the European Communities under the Community Treaties unless Parliament had enacted legislation, Legislation by Parliament was needed to give effect to EU law in the domestic law of the jurisdictions in the United Kingdom as was required by those Treaties and as was necessary to give effect in domestic law to the rights and obligations arising under EU law.

It is common ground that only Parliament could create the necessary changes in national law to allow EU law to have the effect at the level of domestic law which Treaties required. As we have explained at paragraph I above, this don by [fic enactment of the ECA 1972 in contemplation of the United Kingdom becoming parl of the European Communities by accession to the Community Treaties so as 10 allow that to happen. If this legislation had not first been put in place, ratification of the Treaties by the Crown would immediately have resulted in the United Kingdom being in breach of its obligations under them, by reason of the absence of provision for direct effect of EU law in domestic law.

The ECA 1972 as a constitutional statute

In due course, the House of Lords confirmed in R v Secretary of State fbr Transporl, ex p. Factortame Ltd [199()] 2 AC 85 that the ECA 1972 was effective, while it remained on the statute book, to give directly effective EU law superiority even over domestic primary legislation. By virtue of the ECA 1972, the national courts give full effect to EU law as part of the domestic law applied by them.

The provisions of the ECÄ 1972

The long title to the ECA 1972 states that it is:

Section 1(2) sets out various definitions. It defines "the Treaties" to mean the accession treaties described in Part I of Schedule I to the Act, "taken with" further specific treaties entered into since accession which are listed in the subsection:

Section 1(3) stipulates that treaties falling within this general definition are to be identified by a declaration made by Her Majesty by Order in Council, and for treaties made after or incorporating terms agreed after 22 January 1972 such Order in Council must be approved in draft by resolution of each House of Parliament.

Section 2 of the ECA 1972 is headed "General implementation of Treaties. It gives effect to the United Kingdom's membership of the European Union and makes the changes to domestic law that are required as a result of membership

It is common ground that if the United Kingdom withdraws from the Treaties pursuant to a notice given under Article 50 of the TEU, there will no longer be any enforceable EU rights in relation to which this provision will have any applicatione Section 2(1) would be stripped of any practical effect.

Section 2(2) confers power to implement any EU law obligation of the United Kingdom into domestic law, as follows:

Section 3(1) requires the national courts in the United Kingdom to follow the rulings of the CJEU in the interpretation of EU law, as follows:

The right of withdrawal from the .EU

In the end, this difference is not significant for present purposes and does not have to be resolved. Neither side suggested that either interpretation of international law would assist us in addressing the question of law which we have to decide, Since on either view of international law the United Kingdom would in principle have been capable of seeking to withdraw from the relevant Treaties, whether by giving unilateral notice or by making and ratifying an agreement to do so, when enacting the ECA 1972 Parliament must be taken to have had that possibility in minds The question would still have arisen whether Parliament intended that this should be something that the Crown would be able to do through exercise of its prerogative powers without Parliament's interventionæ

Categories of rights arising under the ECA 1972 and EU law

The parties presented a broad schematic account of three different categories of rights arising under EU law. For the purposes of analysis in this case it is helpful to use this scheme, although it is, of necessity, rather simplified* The analysis focuses on rights, but it is important to bear in mind that there are other substantial areas of EU law such as the schemes of regulation which take effect as part of the law of the United Kingdom

Category (ii): rights enjoyed in other Members States of the EU

The second category of rights is those enjoyed by British citizens and companies in relation to their activities in other Member States, as provided for by EU law, for example pursuant to rights of free movement of persons and of capital and rights of freedom of establishment ("category (ii) rights"). If a British citizen resides in another Member State pursuant to EU rights of free movement, EU law requires aciltovitics and courts of that Member State to respect and give effect to those rights€ It also prohibits the authorities in the United Kingdom from placing impediments in the way of the exercise of such rights.

Category (iii): rights that could not be replicated in UK law

The third category of rights is those which have an effect in the domestic law of the United Kingdom and which would be lost upon withdrawal from the European Union and which could not be replicated in domestic legislation ("category (iii) rights"). Mr Eadie QC, on behalf of the Secretary of State, characterised these as rights flowing from the membership of "the EU club". These include the right to stand for selection or, later, for election to the European Parliament and the right to vote in such elections (see paragraph 69 below). The right to seek a reference to the CJEU is another example. So is the right to seek to persuade the EU Commission to take regulatory action in relation to matters within the United Kingdom, such as to investigate a violation of EU competition law or of EU environmental protection legislation occurring within the United Kingdom and grant a remedy in relation to it.

The effect of withdrawal of the rights

As regards category (ii) rights, the prohibition against impediments to the exercise of these rights is part of EU law with direct applicability in the domestic law of the United Kingdom, as the Secretary of State accepts. However, the Secretary of State submits that the main content of these rights (say, the ability of a British citizen to rely on his or her rights of free movement when in another Member State) is not the product of the ECA 1972. Rather, it is the product of the operation of EU law in combination with the domestic law of that Member State, just as the free movement rights of a national of that Member State in England and Wales would be the product of EU law in combination with the domestic law of England and Waless The Secretary of State says, further, that the effect of EU law on other Member States for the benefit of British citizens was brought about by ratification of the relevant EU Treaties by the Crown on behalf of the United Kingdom on the international plane and the reciprocal ratification of those treaties by other Member States, also on the international plane.

In a highly formalistic sense, this may be accurate, But in our view, it is a submission which is divorced from reality. As explained at paragraphs 41-42 above, the enactment of the ECA 1972 was a necessary step before ratification of the relevant Treaties could occur, as Parliament knew. As Parliament contemplated, it was only if it enacted the ECA 1972 (and then amended it to refer to later EU Treaties) that ratification of those Treaties could occur. The realitv is that Parliament knew and intended that enactment of the ECA 1972 would provide the foundation tor the acquisition by British citizens of rights under EU law which they could enforce in the courts of other Member Statess We therefore consider that the claimants are correct to say that withdrawal from the European Union pursuant to Article 50 would undo the category (ii) rights which Parliament intended to bring into effect, and did in fact bring into effect. by enacting the ECA 1972 Although these are not rights enforceable in the national courts of the United Kingdom, they are nonetheless rights of major importance created by Parliament. Accordingly, the claimants are entitled to say rhat it would be surprising if they could be removed simply throuzh action by the Crown under its prerogative powers.

UK legislation in relation to the EU subsequent to the ECA 1972

As mentioned at paragraph 46 above, the ECA 1972 has been amended on a number of occasions to give effect to new EU Treaties as they have been made and ratified by the United Kingdom. This includes amendment of the ECA 1972 by the European Communities (Amendment) Act 2008 ("the 2008 Act") to allow för ratification of the Lisbon Treaty. However, the material provisions of the ECA 1972 set out at paragraphs 4754 above have remained unchanged since 1972, save for additions to the list of EU Treaties in section

Section 6 of the 2008 Act provided for parliamentary control of Ministers before they took any action in relation to certain decisions to increase the powers of the EU institutions. It did not provide for any similar parliamentary control in relation to a decision to give notice under Article 5() of the TEU.

The European Parliamentary Elections Act 2()()2

The European Parliamentary Elections Act 2002 ("the 2002 Act") makes provision in relation to elections to the European Parliament. Section I provides thal there shall be 73 members of the European Parliament elected for the United Kingdom in respect of 12 electoral regions. Section 8 states who is entitled to vote in European parliamentary elections. It is common ground that these provisions will lose their effect if the United Kingdom withdraws from the European Union.

The 2015 Referendum Act provided, in section 1, for the holding of a referendum on the question. "Should the United Kingdom remain a member of the European Union or leave the European Union? Section I (l) simply stated, "'A referendum is to be

The parties' principal submissions

The arguments advanced to the court by all parties were transcribed and made available on the internet free of charge. It is therefore possible to summarise the arguments briefly.

The claimants' primary submissions are as follows:

The Secretary of State submits as follows:

Our decision on the legal question

Rather than begin with our consideration of the claimants' primary submission* to which we turn at paragraph 95, we will consider first the Secretary of State's submission on the interpretation of the ECA 1972 He maintains that under section 2(1 ) of the ECA 1972 the content of EU rights is defined by reference to the EU Treaties, This means that Parliament intended there to be a continuing condition for the existence of any EU rights to be given effect in domestic law under section 2(1), in the shape of the continued membership of the European Union on the part of the United Kingdom; and that whether that condition is satisfied or not was intended by Parliament to depend entirely upon the action of the Crown on the plane of international law.

If the Secretary of State's contention as to the proper meaning of section I ) of ECA 1972 is correct, there is no violation of the principle in The Case Proclamations % summarised in The Zamora, as set out at paragraphs 27-29 above. Parliament would then itself have provided that the EU rights in domestic law should be vulnerable to removal by executive action on the plane of international law through the use of the Crown%s prerogative powers.

This would be a function of the principle of Parliamentary sovereignty, as Parliament can produce any effect it likes in law and so in theory can, if it chooses, legislate in such a way that aspects of the application of a statutory regime may be left to be filled in by reference to formal steps taken by the executive government. Post ()Jfice v Estucuy Radio Ltd [1968] QB 740, CA, is an example of this. In that case, on the proper interpretation of the legislation in question in 'its particular context, the extent of application of the legislative regime was to be determined by reference to the concept of the United Kingdom's territorial waters, as they happened to be defined from time to time by the Crown by making relevant claims regarding their extent in the conduct of international relations under its prerogative powers.

However, in our judgment the Secretary of State goes too far in his suggestion that constitutional principle summarised in The Zamora drops out of the picture and that [he approach to statutory interpretation in relation to abrogation of the Crown's prerogative powers as set out in De Keyser 's Roval Hotel leads to the conclusion that under the ECA 1972 the Crown retained prerogative power to take steps to withdraw the United Kingdom from the Community Treaties and now. therefore, has power under the Crown-s prerogative to give notice under Article 50.

Statutory interpretation, particularly of a constitutional statute which the ECA 1972 is for the reasons ziven at paragraph 43-44 above, must proceed having regard to background constitutional principles which inform the inferences to be drawn as to 'What Parliament

There are several examples of this approach to statutory interpretation. There is a strong presumption against Parliament being taken to have intended to give a statute retrospective effect, even if the language used in the statute might appear to create such effect. There is a similar presumption as to the territorial effect of staluleso Thecc a strong presumption that Parliament does not intend to preclude access to the ordinary courts for determination of disputes: see, for example, Anisminic Ltd v Foreign Compensation Commission [1969] 2 AC 147, Another example, debated at some length at the hearing, is the principle of legality, i.e. the presumption that Parliament does not intend to legislate in a way which would defeat fundamental human rights: see R v Secretary of State for the Home Department, ex p. Pierson [19981 AC 539 at 573G, 575B-G (Lord Browne-Wilkinson) and R v Secretary of State fbr the Home Department, ex p. Simms [2000] 2 AC 115, 131D-G (Lord Hoffmann). All these presumptions can be overridden by Parliament if it so chooses, but the stronger the constitutional principle the stronger the presumption that Parliament did not intend to override it and the stronger the material required, in terms of express language or clear necessary implication, before the inference can properly be drawn that in fact it did so intend, Similarly, the stronger the constitutional principle, the more readily can it be inferred that words used by Parliament were intended to carry a meaning which reflects the principles

We emphasise this feature of the case because the Secretary of State's submission, in our view, glossed over an important aspect of this starting point for the interpretation of the ECA 1972 and proceeded to a contention that the onus was on the claimants to point to express language in the statute removing the Crown's prerogative in relation to the conduct of international relations on behalf of the United Kingdom. The Secretary of State's submission left out part of the relevant constitutional background. It was omitted despite the Secretary of State making recourse to this approach to statutory interpretation a keystone of his own submission that the conduct of international relations is a matter for the Crown in the exercise of its prerogative powers, He made it so in order to argue that express (or at any rate especially clear) language would need to be found in the ECA 1972 before it could be inferred that Parliament intended to remove the Crown ^e s prerogative power to take steps to remove the United Kingdom from the European Communities and the Community Treaties, Despite this. the Secretary of State•s submission on section 2(1) of the ECA 1972 gave no value to the usual constitutional principle that, unless Parliament legislates to the contrary. the Crown should not have power to vary the law of the land by the exercise of its prerogative powers

The principle that the Crown cannot use its prerogative powers (o alter domestic law

In this context, it is also relevant to bear in mind the profound effects which Parliament intended to produce in domestic law by enactment of the ECA 1972, which has led to its identification as a statute of special constitutional significance, The wide and profound extent of the legal changes in domestic law created by the ECA 1972 makes it especially unlikely that Parliament intended to leave their continued existence in the hands of the Crown through the exercise of its prerogative powers. Parliament having taken the major step of switching on the direct effect of EU law in the national legal systems by passing the ECA 1972 as primary legislation, it is not plausible to suppose that it intended that the Crown should be able by its own unilateral action under its prerogative powers to switch it off again.

Moreover, the status of the ECA 1972 as a constitutional statute is such that Parliament is taken to have made it exempt from the operation of the usual doctrine of implied repeal by enactment of later inconsistent legislation: see Thoburn v Sunderland City Council, at [60]-[64], and section 2(4) of the ECA 1972 It can only be repealed in any respect if Parliament makes it especially clear in the later repealing legislation that this is what it wishes to do. Since in enacting the ECA 1972 as a statute of major constitutional importance Parliament has indicated that it should be exempt from casual implied repeal by Parliament itself, still less can it be thought to be likely that Parliament nonetheless intended that its legal effects could be removed by the Crown through the use of its prerogative powers.

l"he Crown 's prerogative power operates only on the international plane

In our judgment, the nub of the court's reasoning, as is apparent from Che passages which we have highlighted, is that ratification of the Protocol on Social Policy by the Crown would not alter or affect the content of domestic law by virtue of section ) of the ECA 1972. Accordingly, there was no good reason to infer that Parliament had intended by enactment of that Act to affect the usual position, properly applicable in relation to that Protocol, that the Crown has untrammelled prerogative powers to make treaties in the conduct of the United Kingdom's international relationso Contrary to the Secretary of State's submission, the judgment cannot properly be read as saying, let alone holding, that express words would be required to futer the Crown's treaty-making power in relation to EU law, since the court looked to see if there was sufficient ground to hold that Parliament had by implication curtailed or fettered the Crown's prerogative in that regard* That question arose in the context of the making of a Protocol to extend, not remove, EU rights. It is clear from the judgment that it was the fact that the ratification of the Protocol would not alter domestic law which led to the court's conclusion. The court did not have to consider an argument as to whether the Crown's prerogative powers had been unaffected by the ECA 1972, In the very different context of the present case, the question is whether the Crown has power under its prerogative to withdraw from the relevant EU Treaties where such withdrawal will, on the Secretary of State's argument, have a major effect on the content of domestic law. It is clear that the court in exp. Rees Mogg did not touch on that question.

C)ur conclusion as to Parliament 's intention

That this was the intention of Parliament and is the effect of the ECA '1972 appears from the following provisions of that Act, read in the light of the relevant constitutional background:

In our judgment, the clear and necessary implication from these provisions taken separately and cumulatively is that Parliament intended EU rights to have effect in domestic law and that this effect should not be capable of being undone or overridden by action taken by the Crown in exercise of its prerogative powers. We therefore reject the Secretary of State's submission that Parliament did not intend to abrogate the Crown's prerogative powers and had not done so through the ECA 1972* Parliament also intended that British citizens should have the category (ii) rights and that, likewise, they should not be capable of being undone by the Crown by exercise of its prerogative powers, We arrive at this conclusion and reject the Secretary of State's submission by interpreting the ECA 1972 as a statute which introduces EU rights into domestic law and must lakeu to cover the field. The ECA 1972 cannot be regarded as silent on the question of what happens to EU rights in domestic law if the Crown seeks to take action on the international plane to undo them. Either the Act reserves power to the Crown to do that, including by giving notice under Article 50, or it does not. In our view, it clearly does not.

The claimants ' principal argument

We have reached this conclusion by examining and rejecting the submission advanced by the Secretary of State. We now turn, as we indicated at paragraph 77 above, to the claimants' principal contention that as a matter of general constitutional principle derived from the sovereignty of Parliament and the case law beginning with The Case of Proclamations, to which we have referred at paragraphs 27-29 above, that the contention of the Secretary of State was misconceived. It was their submission that the Crown could not change domestic law and nullify rights under the law unless Parliament had conferred upon the Crown authority to do so either expressly or by necessary implication by an Act of Parliament. The ECA 1972, in their submission, contained no such authority.

The interpretation of the ECA 1972 we have set out and the conclusions we have reached are fully in line with the guidance given in De Keyser 's Roval flo/eL That case establishes that Crown prerogative powers may be impliedly abrozated by primary legislation: [1920] AC 508 526 (Lord Dunedin), 539 (Lord Atkinson), 554 (Lord Moulton), 561-562 (Lord Sumner) and 575576 (Lord Parmoor). It also provides an example of one kind of case where that will be found to have occurred, i.e. where a matter fönnerly dealt with under the Crown^R s prerogative powers has been directly regulated by statute. In that case, the taking of property bv the Crown during wartime

In fact, the way in which sections 2(1), 2(2) and 3(1) of the ECA 1972 would bc stripped of effect by exercise of the Crown's prerogative powers if che Secreiavy oc State's interpretation of that Act were correct provides an even stronger illustration than that which led the House of Lords in R v Secretary of Stale for the Home Department, ex p. Fire Brigades Union [1995] 2 AC 513 to hold that the Crown's prerogative had been impliedly abrogated by the statute in issue there. That case concerned the Criminal Injuries Compensation Scheme, which had originally been introduced under the Crown's prerogative powers. Parliament enacted legislation to put such a scheme on a statutory footing, applying certain rates of compensation as set out in the statute. The statutory scheme was not brought immediately into effect, but according to the statute the Secretary of State had to keep under review whether he should make an order to bring it into effect. Instead, however, he decided to exercise the Crown's prerogative to make changes to the compensation scheme introduced through the use of the Crown's prerogative powers by specifying tarifT compensation rates which were lower than those set out in the statutory provisions. The House of Lords held that this was unlawful, as the Crown's prerogative power to change the scheme had been impliedly abrogated by the statute to the extent that he was not entitled to exercise it, as he had sought to do, in a manner which in practice meant he debarred himself from exercising the statutory power (to bring the statutory scheme into effect) for the purposes and on the basis which Parliament intended: see pp. 5521)-554G (Lord Browne-Wilkinson), 568G-573C (Lord Lloyd of Berwick) and 575B-578F (Lord Nicholls of Birkenhead). The new tariff scheme was not introduced as a temporary stopgap, but as a long-term replacement for the existing scheme and its statutory embodiment* As Lord Nicholls said at pe 576A-B:

The effect of the decision in the Fire Brigades Union case was that Parliament could not be taken to have legislated in vain, Even though the statutory compensation scheme had not yet been brought into force, the Secretary of State was under a duty to consider bringing it into force at some point. He could not use the Crown's prerogative powers to create a new prerogative scheme which was incompatible with the statutory scheme and was intended to stand in place of it, even lhough the statutory scheme was not yet in effecte In the present case, on the other hands sections 2(1), 2(2) and 3(1) of the ECA 1972 set out legal duties already in force which require effect to be given to EU law, In the present case. contrary 10 the submission of the

It is finally necessary to refer to Laker Airways .Ltd v Department of Trade [1977] QB 643 (CA), on which the claimants relied. In that case the Court of Appeal found that the Crown's prerogative powers in relation to the making of treaties had been impliedly abrogated by a statutory scheme for the licensing of air carrierse The claimant carrier had been licensed under the statute to provide an airline service between London and New York, but the Crown proposed to cancel the designation of the claimant as an approved carrier under the relevant treaty arrangement with the USA, which designation was necessary to allow it to operate its service, The coatt held that this would be unlawful. As ILord Denning MR said, "such a procedure was never contemplated by the statute" (p. 707B). Roskill LJ applied the guidance in De Keyser's Royal Hotel and held that Parliament should be taken to have intended {o fetter the prerogative of the Crown in the relevant respect by its legislation (pp. 719B722H). Lawton LJ likewise held that the legislation regulated all aspects of the revocation of licences and by necessary implication should be construed so as to prevent the Secretary of State from achieving that effect through the exercise of the Crown's prerogative powers (pp. 727B-728D). The analysis of all three judges depended on what Parliament had intended in the primary legislation and was in line with the approach in De Keyser 's Royal Hotel.

Lawton LJ discussed the Secretary of State's submission that there was nothing in the legislation which curbed the Crown's prerogative powers in the sphere of international relations, and that indeed the legislation recognised that the Crown had such powers. Lawton LJ said

The Act of Union 1707, the devolution statutes and other statutes

The 2()15 Referendum Act

The Secretary of State's case regarding his ability to give notice under Article 5() was based squarely on the Crown's prerogative power. I-lis counsel made it clear thal he does not contend that the 2015 Referendum Act supplied a statutory power for the Crown to give notice under Article 50. He is right not to do so. Any argument 10 Chal cifocl have been untenable as a matter of statutory interpretation of the 2()15 Referendum Act.

We emphasise that the Secretary of State's position on this part of the argument and the observations in the preceding paragraphs relate to a pure legal point about the effect in law of the referendum. This court does not question the importance of the referendum as a political event, the significance of which will have to be assessed and taken into account elsewhere.

Conclusion and form of declaratory relief

This case came on before us as a "rolled up" hearing. for the questions of permission to seek judicial review and, if granted, the substantive merits of the claim to be considered at one hearing. We formally grant permission,

For the reasons we have set out, we hold that the Secretary of State does not have power under the Crown•s prerogative to give notice pursuant to Article 50 of the T Et for the United Kingdom to withdraw from the European Union.