9.1 Introduction

Taking the long view, the Withdrawal Agreement (WA) is likely to be remembered for two matters: the position it takes on the protection of citizens’ rights (provisions which have the potential, as we shall see, to last for well over a century) and the provisions of the Protocol which could last indefinitely – or perhaps no longer than four years, depending on the outcome of consent votes in the Northern Ireland Assembly.Footnote ¹ This chapter looks primarily at the effect of the WA in the UK as a whole.Footnote ² It will focus on the implementation of the WA in UK law, the enforcement of rights under the Protocol, as they relate to the UK, and the position of EU citizens and their rights.

9.2 Implementation of the WA into UK Law

The WA, an international treaty, provided for the exit of the UK from the EU. Under the UK’s dualist approach, Parliament was required to legislate in order to give the WA legal effect in the UK. This was accomplished by the European Union (Withdrawal Agreement) Act 2020 (EUWAA 2020) which, in part, amended the European Union (Withdrawal) Act 2018 (EUWA 2018). The WA took effect in UK law from exit day (31 January 2020, at 11.00 pm).Footnote ³ The Trade and Cooperation Agreement (TCA), which regulates future relations between the EU and the UK and applies in tandem with the provisions of the WA, came into effect in the UK via the European Union (Future Relations) Act 2020 (EUFRA) at the end of December 2020.

What was to be done about the significant mass of EU law that applied in the UK prior to the UK’s exit? Although the UK left the EU on 31 January 2020, under the terms of the WA, the UK then entered into a period of transition (or, in British terminology, implementation), which lasted from 1 February 2020 to 11 pm on 31 December 2020, Implementation Period Completion Day (IPCD). During this transition/implementation period, most of EU law continued to apply in the UK, as EU law.Footnote ⁴ EUWA 2018 provided that when the UK finally left the EU, all EU legislation then applying was to be ‘on-shored’ into UK law, becoming ‘retained EU law’ and giving powers to ministers to amend that legislation where retained EU law no longer operates effectively. Section 5(2) EUWA 2018 provides for the continuation of the supremacy of this EU retained law over conflicting pre-Brexit UK law.

The 2018 Act, as amended, gives effect to the whole of the WA (including the Protocol) in UK law and also gives ministers specific powers to implement matters affecting the Protocol. The principal conduit pipe for the incorporation of the UK’s obligations under the WA is section 7 A EUWA 2018 (‘General implementation of remainder of withdrawal agreement’), introduced as a result of section 5 of EUWAA 2020. The key parts of section 7 A provide:

The striking feature of section 7 A is how far it draws on the controversial language of section 2(1) European Communities Act 1972 (ECA 1972),Footnote ⁵ which had been read to give direct effect and supremacy to EU law, and was viewed in UK law as constituting a ‘constitutional statute’. We will return to this point later.

The rights of EU citizens in Part Two of the WA apply to the UK, as do the provisions of the Protocol, since section 7 A applies to the territory of the UK as a whole.Footnote ⁶ In addition, section 8C of the 2018 Act (‘Power in connection with Ireland/Northern Ireland Protocol in withdrawal agreement’) provides additional powers to implement the Protocol. A minister of the Crown may by regulations make such provision as the minister considers appropriate –

1. (a) to implement the Protocol on Ireland/Northern Ireland in the withdrawal agreement,

2. (b) to supplement the effect of section 7 A in relation to the Protocol, or

3. (c) otherwise for the purposes of dealing with matters arising out of, or related to, the Protocol (including matters arising by virtue of section 7 A and the Protocol).

9.3 Enforcement of Rights

9.4 Citizens’ Rights

9.5 Conclusions

The relationship between the UK and the EU during the first few months after the end of the transition/implementation period was described as ‘a bit bumpy’.Footnote ²⁶ The UK’s reaction to handling the hypersensitive issue of the Protocol made matters more difficult. The EU followed up what it saw as the UK’s non-compliance, triggering the dispute settlement procedures under the WA, albeit this is currently suspended. Private parties may also enforce their rights, but at the time of writing there was no example of this. Meanwhile, EU citizens with settled status enjoy protection similar to that under EU law and also benefit from a robust enforcement mechanism.

10.1 Introduction

This chapter provides an overview of the Protocol’s position in Northern Ireland law. It does so by focusing on the ‘legal hybridity’ that results from the application of different legal rules under and outside the Protocol. While Northern Ireland is still formally a part of the UK,Footnote ¹ the reality is that its legal and political institutions now have obligations in relation to two constitutional orders. It is a point that will remain true for so long as the Protocol is in force: presently for four years, with the option of extension by ‘democratic consent’.Footnote ²

The chapter has two main objectives. The first is to consider the nature of the legislative framework that has given effect to Brexit and how that intersects with the Northern Ireland Act 1998 (NI Act 1998). In terms, this is a point about overlapping ‘constitutional statutes’ and whether the Brexit legislation – principally the European Union (Withdrawal) Act 2018 (as amended) (EUWA 2018) – is consistent with all aspects of the Northern Ireland ‘constitution’ (ie, the Belfast-Good Friday Agreement 1998 (1998 Agreement) and the NI Act 1998).Footnote ³ Certainly, the Protocol is said in Article 1 to have the express objective of safeguarding the 1998 Agreement ‘in all its dimensions’, whether those relate to (for instance) the protection of rightsFootnote ⁴ or North–South co-operation.Footnote ⁵ However, it has since been argued in proceedings in the domestic courts that aspects of the Northern Ireland constitution have been weakened by the legislation that gives domestic legal effect to the Protocol, in ways that contradict the logic of case law on constitutional statutes.Footnote ⁶ This chapter assesses the strength of those arguments and asks whether legal hybridity itself is contrary to parts of the Northern Ireland constitution.

The second objective is to consider the nature of the obligations that arise under and outside the Protocol. In the first instance, this is a point about the ongoing application of aspects of EU law in Northern Ireland, where Article 4(1) of the Withdrawal Agreement (WA) reads:

While the corpus of EU law that has effect in this way does so by reason of an international Treaty, Article 4 appears as a reformulation of the supremacy doctrine that was developed in case law such as Costa v Enel and Simmenthal.Footnote ⁷ This is where the legal hybridity of the Protocol takes form, as, to the extent that Northern Ireland’s institutions are bound by norms of EU law under the Protocol, they must follow different rules when engaged in decision-making outside it. The chapter identifies the legal basis for the application of those different rules and ‘who’ must do ‘what’, and ‘when’, as a matter of Northern Ireland law.

10.2 The EUWA 2018 and the Protocol

The legal hybridity that has been created by the Protocol starts with EUWA 2018, as amended by the European Union (Withdrawal Agreement) Act 2020 (EUWAA 2020). The first purpose of EUWA 2018 is, of course, to make provision for the domestic law effects of Brexit, where it governs decision-making outside the Protocol not just in Northern Ireland but in the UK more widely. The relevant sections of the Act are considered in Chapter 9 in this volume,Footnote ⁸ and only the following features are noted here: (i) the Act of 2018 expressly repealed the European Communities Act 1972 (ECA 1972) but kept many aspects of EU law on the statute book as ‘retained EU law’;Footnote ⁹ (ii) the principle of supremacy no longer applies on its original terms, albeit the courts can still have regard for rulings of the Court of Justice of the European Union (CJEU) when interpreting retained EU law;Footnote ¹⁰ (iii) references to Article 267 of the Treaty on the Functioning of the European Union (TFEU) are not possible, and nor is the Charter of Fundamental Rights (CFR) a part of domestic law;Footnote ¹¹ (iv) retained EU law can be modified by the devolved institutions in Northern Ireland in areas within their competence but not where particular aspects of EU law are specified in regulations made by a minister of the Crown;Footnote ¹² and (v) the general principles of EU law now have only a limited reach in domestic law and, post-Brexit, Francovich actions are not possible.Footnote ¹³

The primary provision of the EUWA 2018 in terms of decision-making under the Protocol is section 7A, inserted by EUWAA 2020. Titled ‘General implementation of remainder of withdrawal agreement’, this section provides: ‘(2) The rights, powers, liabilities, obligations, restrictions, remedies and procedures [in the WA] are to be – (a) recognised and available in domestic law, and (b) enforced, allowed and followed accordingly’; and ‘(3) Every enactment (including an enactment contained in this Act) is to be read and has effect subject to subsection (2)’.

The full significance of section 7 A becomes apparent when it is read beside Article 4(1) WA (above) and Articles 12(4) and 13(2)–(4) of the Protocol, as these embed EU law (including its general principles and remedies) into the law of Northern Ireland. Article 4(1)’s specific effect is thus to make the provisions of EU law listed in the Protocol applicable in Northern Ireland, where Article 12(4) provides, as regards Articles 5 and 7–10 of the Protocol (and their Annexes), that the CJEU ‘shall have the jurisdiction provided for in the Treaties in this respect. The second and third paragraphs of Article 267 TFEU shall apply to and in the United Kingdom in this respect.’ Article 13(2)–(4) in turn reads:

Section 7 A is not the only provision of EUWA 2018 that gives effect to the Protocol – for instance, section 8C confers on ministers of the Crown wide regulation-making powers in relation to it, and section 10 (on protection for North–South co-operation) was amended in the light of Article 11 of the Protocol.Footnote ¹⁴ However, for the purposes of legal hybridity, section 7A, as read with the Act more generally, establishes the different sets of rules that must be followed by Northern Ireland’s institutions, including its courts. While it might be argued that such hybridity is simply a carry-over of the hybridity that applied under the ECA 1972 – where UK courts frequently observed different procedural and substantive rulesFootnote ¹⁵ – the fact that aspects of EU law now apply in only Northern Ireland means that the analogy is not a perfect one. In short, while EU law had previously applied throughout the UK as a whole and in the light of the wider devolution settlement, the Protocol has placed Northern Ireland in a truly unique position. Indeed, it may, on one reading, even be queried whether ‘legal hybridity’ is a strong enough descriptor: economic constitutionalism and the EU’s historical experience with sectoral integration might suggest that something more fundamental is afoot.Footnote ¹⁶

10.3 The NI Act 1998 and the Protocol

The Protocol has also been implemented through amendment of the NI Act 1998 – and some parts of the Act can now be understood only when read alongside provisions of EUWA 2018. While it is arguable that the ‘catch-all’ nature of section 7 A EUWA 2018 would have made all necessary changes by implication (albeit that would raise a question about the interplay of ‘constitutional statutes’; see Section 10.4), the reality is that the complexities of the Protocol required further, specific changes to the NI Act 1998. Those complexities are, of course, a result of the complexities of the 1998 Agreement itself, as the Protocol is intended to protect that Agreement ‘in all its dimensions’.Footnote ¹⁷ Four provisions of the Protocol in this regard are of particular importance.

The first provision is Article 2, which relates to the protection of rights and, as a result of sections 6(2)(ca) and 24(1)(aa) of the NI Act 1998, now limits the powers of the devolved institutions. The implications of that Article are considered in more detail in a subsequent chapter and will not be analysed in any depth here.Footnote ¹⁸ However, one point that can be made concerns the CFR and the range of Directives that is listed in Annex I to the Protocol. This is one area where the dynamism of the CFR might well continue to be evident in Northern Ireland law, as the CJEU may draw upon it if required to rule upon the meaning of the Directives – or, indeed, new Directives within the scope of the Protocol – in the future.Footnote ¹⁹ In the event that it were to do so, the Northern Ireland courts would be required to follow that case law by reason of Article 13(2), which states that: ‘the provisions of this Protocol … shall in their implementation and application be interpreted in conformity with the relevant case law of the [CJEU]’. The contrast with the position under section 5 EUWA 2018 – which provides that the CFR does not apply in UK law more generally – could well become of more than passing significance.

The second provision is Article 11, which states that the Protocol ‘shall be implemented and applied so as to maintain the necessary conditions for continued North–South cooperation, including in the areas of environment, health, agriculture, transport, education and tourism, as well as in the areas of energy, telecommunications, broadcasting, inland fisheries, justice and security, higher education and sport’. This is one area where the NI Act 1998 is to be read alongside EUWA 2018, as section 10 of that Act (among others) safeguards the multilayered arrangements that underlie North–South co-operation. Such co-operation was envisaged by Strand Two of the 1998 Agreement (as supported by the British–Irish Agreements of 1998 and 1999), and it takes form in Northern Ireland law in, inter alia, a ministerial duty to participate in meetings of the North–South Ministerial Council, and the possible exercise of legislative powers in relation to agreements reached there.Footnote ²⁰ The multilayered nature of these arrangements is such that the legal structures for co-operation are found in international law but with a basis in political agreement in Northern Ireland, and this is where section 10 EUWA 2018 becomes significant. Originally enacted before the Protocol was agreed, it was amended in its light and now does three main things: (1) it imposes a duty on ministers of the Crown and Northern Ireland ministers and departments to act compatibly with the NI 1998 when exercising powers under EUWA 2018; (2) it prohibits ministers of the Crown from making regulations which would diminish any form of North–South co-operation as provided for by the 1998 Agreement or which would facilitate physical border infrastructure on the island of Ireland; and (3) it prohibits a minister of the Crown from agreeing to any recommendation by the Protocol’s Joint Committee (JC) that would alter the arrangements for North–South co-operation in the 1998 Agreement, establish a new implementation body, or alter the functions of an existing implementation body. Point (3) would suggest that any such changes would be possible only through a further British–Irish agreement, where previous agreements have been contingent upon political agreement within Northern Ireland itself.Footnote ²¹

The third provision is Article 13(4). This envisages the adoption by the EU of an act which may either amend or replace existing acts in the Protocol or be in the form of a new act ‘that falls within the scope of this Protocol’. This is where the Protocol is arguably at its most controversial in terms of democratic principle, as it gives the UK government only a peripheral role in relation to such acts and attributes no role at all to the Northern Ireland institutions. Domestic law does, however, oblige those institutions to track developments in relation to Articles 2, 5 and 7–10 of the Protocol, where the Secretary of State has a power under section 26(2) of the NI Act 1998 to make an order in relation to the discharge of international obligations. While it is, of course, unclear quite how those obligations will develop in the future, they lend themselves to a more general point about the Northern Ireland institutions existing as ‘rule-takers’ under the Protocol, rather than as ‘rule-makers’. They are, moreover, rule-takers who could potentially be liable for ‘sufficiently serious’ breaches of EU law in accordance with the ‘Francovich’ principle – such is the combined effect of Article 4(1) WA and section 7A(2) EUWA 2018.

The fourth provision is Article 18, which is titled ‘Democratic consent in Northern Ireland’. This Article provides that, four years after the end of the transition period, the UK government must ‘seek democratic consent in Northern Ireland in a manner consistent with the 1998 Agreement’ for the continued application of Articles 5–10 of the Protocol. A number of possible outcomes are envisaged by the Article: (i) a majority of members of the Northern Ireland Assembly (the Assembly) may vote to continue the application of Articles 5–10, in which instance they will apply for a further four years; (ii) there is ‘cross-community’ support (ie, majority support within unionism and nationalism) for the continued application of Articles 5–10, in which instance they will apply for a further eight years; and (iii) a majority of members of the Assembly may vote not to continue the operation of Articles 5–10. In this third instance, Articles 5–10 will remain in force for a further two-year period during which time the JC must make recommendations about future arrangements ‘taking into account the obligations of the parties to the 1998 Agreement’.

The mechanisms for obtaining such consent are a matter for the UK alone,Footnote ²² and the NI Act 1998 has since been amended by regulations made under EUWA 2018.Footnote ²³ The primary amendments are found in Schedule 6 A to the NI Act 1998, which makes provision for a ‘default democratic consent process’Footnote ²⁴ and an ‘alternative democratic consent process’.Footnote ²⁵ Of particular note is paragraph 18 of the Schedule, which ‘applies in relation to any motion for a consent resolution whether the default democratic consent process or the alternative democratic consent process is applicable’.Footnote ²⁶ According to that paragraph, the Assembly may vote on a consent motion only once and, by paragraph 18(5), section 42 of the NI Act 1998 ‘does not apply in relation to a motion for a consent resolution’. Section 42 governs the ‘petition of concern’ mechanism whereby either of Northern Ireland’s two main ethno-national groups can veto measures with which they disagree, and the regulations that inserted Schedule 6 A have thus written out a key feature of the original 1998 Agreement. The significance of this point is returned to in Section 10.4.

10.4 Constitutional Statutes and the Protocol

The remaining matter to be addressed in this chapter is how to conceive of the interplay between EUWA 2018 and the NI Act 1998. As noted in the introduction, this is a point about ‘constitutional statutes’ and how far that imagery can illuminate the relationship between the Acts. The term is famously associated with Laws LJ’s ruling in Thoburn, where he said:

While Thoburn concerned the effects of ECA 1972 – which, as a constitutional statute, was said to lie beyond the rules of implied repeal – Laws LJ identified a list of other qualifying statutes that included Magna Carta, the Bill of Rights, the Union with Scotland Act 1706, the Human Rights Act 1998 and the devolution legislation for Scotland and Wales.Footnote ²⁸ It is a commonplace that the NI Act 1998 is also a constitutional statute.Footnote ²⁹

Two questions arise from this. The first is whether EUWA 2018 ought to be regarded as a constitutional statute, where it would appear that the answer can only be yes. Not only does EUWA 2018 have elements of both (a) and (b) from Laws LJ’s definition; it has been enacted in the very constitutional space that was previously occupied by ECA 1972. Indeed, the similarities with ECA 1972 can be seen in the fact that section 7 A EUWA 2018 has largely the same effects as section 2 ECA 1972 – a ‘catch-all’ means of incorporation linked to a requirement to read ‘all other enactments’ in the light of the incorporated law.Footnote ³⁰ The similarities can also be seen in the fact that EUWA 2018 has replaced ECA 1972 as an ‘entrenched enactment’ under section 7 of the NI Act 1998. This means that EUWA 2018 ‘shall not be modified by an Act of the Assembly or subordinate legislation made, confirmed or approved by a Minister or Northern Ireland department’.Footnote ³¹

The second question is what does this all mean in practice? Certainly, much will depend on how the courts regard Laws LJ’s statement about constitutional statutes not being subject to implied repeal, and repeal being possible only through the use of ‘express words’. While the out-workings of this are uncontroversial when a constitutional statute is succeeded by an ‘ordinary’ Act of Parliament, the position is more complex where one constitutional statute (the NI Act 1998) has points of cross-over with another constitutional statute (EUWA 2018). The point can again be developed with reference to section 7 A EUWA 2018, as the rules on implied repeal would mean that, were there to be any conflict between the WA and the NI Act 1998, the WA would automatically prevail. However, the difficulty with that approach is that it inverts the logic of Thoburn, unless it can be said that Laws LJ intended for his statement of principle to apply at only the interface between ‘constitutional’ and ‘ordinary’ statutes. There is nothing in the judgment to suggest that he intended for it to be limited in that way.

These are not simply points of abstract interest, as related questions about constitutional statutes are presently before the courts in Northern Ireland.Footnote ³² While the issue of implied repeal has arisen in those proceedings in the context of a challenge to the Protocol’s effects on the Act of Union between Ireland and Britain, the proceedings also challenge the lawfulness of the regulations that inserted Schedule 6 A into the NI Act 1998. As already discussed, those regulations have written out the ‘petition of concern’ mechanism from the democratic consent process and, in so doing, have modified a key feature of the Northern Ireland constitution. Although there are strong practical reasons for limiting the petition’s effects in this way – its use could potentially frustrate any future consent motion within the Assembly – the more fundamental point is whether it ought to be possible to change a constitutional statute by way of regulations made under another constitutional statute. Prior to Brexit, the case law on devolution may well have suggested that this should not be possible, as the courts had acknowledged the importance of the devolution settlement throughout the UK and its localized, democratic basis.Footnote ³³ However, the case law since Brexit has equally seen the courts return to a more absolutist view of the Westminster Parliament’s powers and, in particular, a Diceyan view of legal sovereignty.Footnote ³⁴ It is a retreat that may ultimately answer all questions in favour of the most recent constitutional statutes.

10.5 Conclusion

This chapter began by noting that it had two main objectives: to consider the nature of the legislative framework that has given effect to Brexit and how that intersects with the NI Act 1998; and to consider the nature of the obligations that arise under and outside the Protocol. It has referred throughout to ‘legal hybridity’ and the idea that the Northern Ireland institutions must observe different rules under and outside the Protocol. In terms of the Assembly and the Executive, this means that they are able to modify aspects of ‘retained EU law’ in matters outside the Protocol but that, in matters under the Protocol, they are bound by the first principles of EU law in relation to all provisions of the Protocol. In terms of the courts, EU law no longer applies on its original terms in cases outside the Protocol, but it does apply with its full force in cases under it. At its height, this means that the courts must apply the supremacy principle, observe the CFR, make Article 267 TFEU references in relation to issues arising under Article 5, 7–10 and 12(2) of the Protocol, apply the general principles of EU law, and hear Francovich claims.

Is this legal hybridity inconsistent with the Northern Ireland constitution? Much of the answer to this question will be found in the ongoing proceedings before the Northern Ireland courts, where historical and contemporary dimensions to the constitution are in issue. Should the courts ultimately hold that the Protocol and its means of implementation have breached foundational constitutional principle, the EU and the UK may well be required to revisit the international law basis of their future relationship. In the event that the courts rule that the Protocol is not inconsistent with the Northern Ireland constitution, legal hybridity may become one of its defining features.

11.1 Introduction

Brexit involves a fundamental reshaping of relations between the UK and the EU and its member states, including Ireland. As the Preamble to the Protocol recognizes, this represents ‘a significant and unique challenge to the island of Ireland’. Since the conclusion of the 1998 Agreement, the EU has provided a critically important, if often invisible, underpinning of the peace process in Ireland. In the wake of Brexit, Northern Ireland is a ‘place between’.Footnote ¹ On the one hand, it is no longer part of the EU and Protocol Article 4 confirms that it is part of the customs territory of the UK. On the other hand, under the Withdrawal Agreement (WA) and the Protocol, Northern Ireland retains its special relationship with Ireland and remains subject to a substantial body of EU law.Footnote ² If Brexit involves a shift in the legal framework for EU–UK relations from EU law to international law, that shift is incomplete, particularly for Northern Ireland. And, for Ireland, including in its relations with Northern Ireland, Brexit serves to reinforce the bonds with the EU. This is reflected in the role and status of the Protocol in Irish law, which is examined in this chapter.

The chapter begins by exploring the formal status and effect of the Protocol in the Irish legal system. As part of an international agreement concluded by the EU, the Protocol takes effect in Irish law as EU law. However, its formal status is only part of the story. The Protocol has a wider influence on the legal framework governing relations among Ireland, Northern Ireland and the UK. For this reason, the chapter also considers how the Protocol has, first, contributed to the formalization in Irish law of the Common Travel Area (CTA) between Ireland and the UK and, second, brought the 1998 Agreement for the first time within the purview of EU law. In these ways, the Protocol adds an increasingly important EU dimension to the legal framework governing relations on the island of Ireland and between Ireland and the UK.

11.2 The Status and Effect of the Protocol in Irish Law

The shifting legal framework governing EU–UK relations is evident in the status of the Protocol in the UK and Irish legal systems. While both Ireland and the UK have traditionally adopted a dualist approach to international agreements, Ireland’s continued membership of the EU is critical in determining the effect of the Protocol in Irish law.

In the UK, although the conclusion of the WA was of great political significance, ‘it had no legal effect within the UK legal order’.Footnote ³ In accordance with the dualist approach, revived in respect of EU international agreements following Brexit, domestic legislation was necessary to give effect to the WA and the Protocol in UK law.Footnote ⁴

By contrast, in Ireland, the dualist approach to international agreementsFootnote ⁵ remains significantly qualified by the wide constitutional immunity afforded to EU law.Footnote ⁶ No provision of the Constitution invalidates laws enacted, acts done or measures adopted by the state that are necessitated by the obligations of EU membership or prevents such laws, acts or measures from having the force of law in the state.Footnote ⁷ This is complemented by the European Communities Act 1972 (as amended) (ECA 1972), which recognizes that acts of the EU institutions are ‘binding on the State’ and form part of domestic law ‘under the conditions laid down in the treaties governing the European Union’.Footnote ⁸ It is through this mechanism that EU law – including the EU’s international agreements – takes effect within the Irish legal order.Footnote ⁹

The Protocol forms an ‘integral part’ of the WA, the international agreement concluded between the EU and the UK to ensure an orderly withdrawal process.Footnote ¹⁰ In accordance with Article 216(2) of the Treaty on the Functioning of the European Union (TFEU), agreements concluded by the Union ‘are binding upon the institutions of the Union and on its Member States’. The Court of Justice of the European Union (CJEU) has long recognized that, upon their entry into force, international agreements concluded by the Union form ‘an integral part’ of EU law and, for the purposes of Article 267 TFEU, are regarded as an act of the EU institutions.Footnote ¹¹ In this way, upon the entry into force of the WA on 1 February 2020, the Protocol became an integral part of EU law and, by extension, Irish law.

While these principles do not necessarily resolve all questions relating to the internal effect of an international agreement within the EU legal order,Footnote ¹² the CJEU has recognized that the parties to an international agreement are free to agree the effects within their internal legal order.Footnote ¹³ In Article 4 WA, the EU and the UK do just that. Having confirmed that the provisions of the WA and the provisions of EU law made applicable by it shall produce the same legal effects for the UK as for the EU and its member states, Article 4(1) WA goes on to provide that ‘legal or natural persons shall in particular be able to rely directly on the provisions contained or referred to in this Agreement which meet the conditions for direct effect under Union law’. This approach stands in direct contrast to the position under the Trade and Cooperation Agreement (TCA).Footnote ¹⁴

It follows that, where provisions of the Protocol meet the conditions for direct effect under EU law, they too may be relied upon directly by legal or natural persons in the context of any disputes concerning the Protocol. Indeed, this extends further to the decisions adopted by the Joint Committee (JC) established under the WA. Article 166(2) expressly provides that such decisions are binding on the Union and the UK and that both parties shall implement those decisions, which shall have ‘the same legal effect’ as the Agreement itself.Footnote ¹⁵ In addition, and of considerable practical importance, Article 4(3) and (4) WA requires that the provisions of the Agreement (and by extension the Protocol) which refer to EU law be interpreted in a manner consistent with EU law.

The significance of the Protocol’s status as an international agreement concluded by the EU is not confined to its binding character or its capacity to be directly effective. In the EU legal order, international agreements occupy an intermediate status between EU primary and secondary law: while they must comply with the Treaties, international agreements prevail in the event of conflict with EU secondary legislation.Footnote ¹⁶ Moreover, for member states such as Ireland, the principle of the primacy of EU law means that international agreements concluded by the EU, such as the Protocol, would prevail over any inconsistent domestic law, even of constitutional status.Footnote ¹⁷

In short, the Protocol – as an integral part of an international agreement concluded by the EU – is endowed with the full force and effect of EU law within the Irish legal system. This greatly facilitates the application and implementation of the Protocol in Irish law. Given that most of the core obligations under the Protocol are directed at the UK, it remains to be seen to what extent disputes concerning the Protocol will arise before the Irish authorities and the Irish courts.Footnote ¹⁸ However, even if the direct implications for Irish law prove limited in practice, the Protocol will nonetheless have a broader influence on the Irish legal system, serving as a vital reference point in relations between Ireland and its nearest neighbour, in the context of both the CTA and the constitutional settlement under the 1998 Agreement.

11.3 The Common Travel Area

While the Protocol may not require any specific implementing measures in Irish law, its presence can be felt in Irish law in the increasing formalization of the CTA between Ireland and the UK.Footnote ¹⁹

At its core, the CTA allows Irish and UK nationals to enter and reside in each other’s jurisdictions. Over time, this has been supplemented by arrangements providing for access to work, health care, social welfare, education, as well as other measures such as voting rights in local and parliamentary elections.Footnote ²⁰ Although the CTA is long established, Brexit exposed its relatively fragile legal basis. In legal terms, the CTA has traditionally been based on ‘a combination of informal administrative understandings and latterly more formal “sectoral agreements”’ which are then reflected in domestic law and practice.Footnote ²¹

When both Ireland and the UK were members of the EU and remained outside the Schengen system, this informal system gave rise to little difficulty. Indeed, Article 2 of Protocol No 20 to the TFEU – under which the UK and Ireland were entitled to control their own borders – allowed the two states to continue ‘to make arrangements between themselves relating to the movement of persons between their territories (“the Common Travel Area”)’ while fully respecting the rights of persons exercising their right of free movement under EU law. However, with the departure of the UK from the EU, the status of the CTA became much more precarious.

From an early stage, there was a political commitment to preserving the CTA. This was confirmed in the Joint Report of the EU and UK negotiators in December 2017.Footnote ²² Later, in the Memorandum of Understanding and Joint Declaration of 8 May 2019, the Irish and UK governments reaffirmed their commitment to the CTA.Footnote ²³ That political commitment was ultimately reflected in Protocol Article 3, which provides, first, that the UK and Ireland ‘may continue to make arrangements between themselves relating to the movement of persons between their territories (“the Common Travel Area”), while fully respecting the rights of natural persons conferred by Union law’. Second, Article 3(2) requires the UK to ensure that the CTA and the rights and privileges associated therewith ‘can continue to apply without affecting the obligations of Ireland under Union law, in particular with respect to free movement to, from and within Ireland for Union citizens and their family members, irrespective of their nationality’. Article 3 thus strengthens the formal recognition of the CTA in EU law and permits its continued operation subject to its consistency with EU law and, specifically, the right of free movement.Footnote ²⁴

For its part, the Oireachtas (the Irish Parliament) has enacted a series of measures to place the CTA on a firmer legal footing in Irish law. The Minister for Health has been given the power to adopt measures providing for health care and reimbursement arrangements in accordance with the Memorandum of Understanding on the CTA.Footnote ²⁵ The Minister for Social Protection is empowered to make an order providing for the implementation of the 2019 Convention on Social Security between the Irish and UK governments which ensures the continuity of social protection arrangements under the CTA.Footnote ²⁶ The definition of ‘non-national’ in Irish law is amended so as to ensure that a UK citizen does not come within that definition, thereby retaining the legal basis for the exemption of UK citizens from passport checks within the CTA.Footnote ²⁷ The enactment of this legislation to protect and maintain the CTA was described as ‘a key part of Ireland’s planning and preparations’ for Brexit.Footnote ²⁸

However, the greater formalization of the CTA in Irish and EU law is not without its challenges. With the departure of the UK from the EU, the scope for tension between the CTA and EU law increases. As the terms of Protocol Article 3 make clear, the CTA is permitted to continue subject to the requirement that it does not affect the obligations of Ireland under EU law, particularly in the context of free movement. If measures of Irish law afford non-EU citizens more favourable treatment than EU citizens in areas falling within the scope of the Treaties, they would be vulnerable to challenge.Footnote ²⁹ Recent debates around travel-related restrictions necessitated by Covid-19 show that this concern is not merely academic.Footnote ³⁰ While Protocol Article 3 may assist in justifying measures adopted as part of the CTA, it is far from a blanket defence. In conclusion, while the recognition of the CTA in the Protocol has reinforced its formal status in EU and Irish law, it also means that the continued existence and development of the CTA will be increasingly influenced by its consistency with EU law.

11.4 The 1998 Agreement

Of even greater constitutional significance for Ireland is the Protocol’s express affirmation of the 1998 Agreement. Since it was concluded, the 1998 Agreement has been the overarching framework governing relations across Ireland, the UK and Northern Ireland. The constitutional changes necessitated by the 1998 Agreement have been described as ‘arguably the most momentous’ since the adoption of the 1937 Irish Constitution.Footnote ³¹ By referendum, the Irish people voted to allow the state to conclude the British–Irish Agreement, the intergovernmental agreement which formed part of the 1998 Agreement, and to amend Articles 2 and 3 of the Irish Constitution. Whereas Article 2 in its original form had defined the national territory as consisting of ‘the whole island of Ireland, its islands and the territorial seas’, the new Article 2 recognized the entitlement and birthright of every person born in the island ‘to be part of the Irish Nation’. For its part, the new Article 3 expressed ‘the firm will of the Irish Nation, in harmony and friendship, to unite all the people who share the territory of the island of Ireland, in all the diversity of their identities and traditions’, while recognizing that a united Ireland could be brought about only ‘by peaceful means with the consent of a majority of the people, democratically expressed, in both jurisdictions in the island’. Although the 1998 Agreement as such does not directly form part of Irish law,Footnote ³² it occupies a central place in Ireland’s constitutional landscape.

Prior to Brexit, the relationship between the 1998 Agreement and EU law might have been described as largely silent but mutually supportive. For its part, the 1998 Agreement makes very limited reference to the EU. The Preamble to the British–Irish Agreement refers to the close co-operation between Ireland and the UK ‘as friendly neighbours and as partners in the European Union’. Under Strand Two of the Multi-party Agreement, one of the tasks of the North–South Ministerial Council is to ‘consider the European Union dimension of relevant matters, including the implementation of EU policies and programmes and proposals under consideration in the EU framework’, with arrangements to be made ‘to ensure that the views of the Council are taken into account and represented appropriately at relevant EU meetings’.Footnote ³³ Under Strand Three, EU issues are identified among the suitable issues for early discussion in the British–Irish Council.Footnote ³⁴ Prior to the Protocol, however, the 1998 Agreement did not feature in any significant way within the wider body of EU law.Footnote ³⁵

However, the relative silence in formal terms belies the critical role of the EU in practice, both in the political backdrop to the 1998 Agreement and in its effective implementation.Footnote ³⁶ As discussed in Chapter 1, common EU membership played ‘a positive part in providing an important supporting structure for several elements of the 1998 Agreement itself’, as well as providing extensive funding of projects relating to the peace process and the Irish border.Footnote ³⁷ In many ways, the 1998 Agreement and the forms of co-operation which it set in train were premised on the continuing EU membership of the UK and Ireland.

With Brexit, this largely silent and invisible underpinning of the peace process has been forced to the surface. At its heart, the Protocol is a response to the ‘significant and unique challenge’ that Brexit presents for the island of Ireland and the peace process.Footnote ³⁸ It is in this context that the EU and the UK expressly affirm that the 1998 Agreement ‘should be protected in all its parts’. The Protocol treads a careful path in this regard.

On the one hand, the Protocol recognizes that the constitutional status of Northern Ireland is not a matter of EU law.Footnote ³⁹ Thus, in its first and second paragraphs, Protocol Article 1 provides that the Protocol is without prejudice to the provisions of the 1998 Agreement in respect of the constitutional status of Northern Ireland and the principle of consent and that the Protocol respects the essential state functions and territorial integrity of the UK.Footnote ⁴⁰

On the other hand, the whole purpose of the Protocol is to set out ‘arrangements necessary to address the unique circumstances on the island of Ireland, to maintain the necessary conditions for continued North–South cooperation, to avoid a hard border and to protect the 1998 Agreement in all its dimensions’.Footnote ⁴¹ The commitment to the 1998 Agreement is reflected in the operative provisions of the Protocol: from Article 2, which protects the rights and values which underpin the peace process, through Articles 5 to 10, which seek to avoid a hard border on the island of Ireland, to Article 11, which aims to facilitate ongoing North–South co-operation and, of course, Article 18, which enshrines the principle of democratic consent in Northern Ireland within the Protocol. In this way, the Protocol provides a mechanism for ensuring that the continued application of the 1998 Agreement is not unduly impaired by the UK’s departure from the EU. Indeed, while the Protocol formally does not make it part of EU law, through both its affirmation of the 1998 Agreement and its substantive provisions, the Protocol gives the 1998 Agreement a mooring in EU law which may allow it to be relied upon, if only indirectly, in litigation before the national and EU courts.Footnote ⁴²

It follows that, even if the major constitutional questions concerning Northern Ireland do not come within its scope, the wider constitutional significance of the Protocol should not be underestimated. It is within the framework of the Protocol that many important issues affecting Northern Ireland, including in the context of North–South co-operation, will fall to be determined in future. And within this framework – in the context of implementation, governance and dispute settlement – it is the EU institutions, rather than any individual member state such as Ireland, that will act as the primary interlocutor. The early experience with the Protocol – particularly in the context of the safeguards regime under Article 16Footnote ⁴³ – offers a foretaste of some of the difficulties and sensitivities to which this changed framework may give rise.

As McCrudden has described the position, the Protocol has ‘to an extent, “Europeanised” the 1998 Agreement, meaning that upholding that Agreement has become an EU objective in the context of the WA, and no longer simply a UK–Irish objective’.Footnote ⁴⁴ Just as the duties of good faith and sincere co-operation in Article 5 WA are likely to ‘play a significant role in future disputes between the UK and the EU over the application of the Protocol’,Footnote ⁴⁵ the duty of sincere co-operation under Article 4(3) TEU – between the Union and Ireland as member state – is likely to take on very considerable importance in this legally and politically sensitive context. Close and continuous co-operation between the Commission and the Irish government will be essential to ensure the effective implementation of the Protocol in a manner which is consistent with the 1998 Agreement and which avoids its underlying objectives being undermined.

11.5 Conclusion

If, for the UK, Brexit has shifted EU–UK relations from the special regime of EU law to the looser bonds of international law, for Ireland, Brexit has served to reinforce and intensify the state’s membership of the EU. In doing so, it has placed Ireland’s relations with the UK within a more direct and increasingly important EU framework. In the context of Northern Ireland, this is exemplified by the Protocol, which seeks to address ‘the unique circumstances on the island of Ireland through a unique solution’. It is also reflected in the status and role of the Protocol in the Irish legal system. It is not simply that the Protocol takes effect in Irish law as EU law, significant though this is. The Protocol has a much wider significance for Ireland in the post-Brexit era, in particular by providing a mechanism through which the long-standing arrangements in the form of the CTA and the constitutional settlement enshrined in the 1998 Agreement can be reconciled with Ireland’s obligations under EU law. Legally, politically and practically, this will give the EU a greater role in the future of the peace process on the island of Ireland.