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Protocoligorically correct

Protocoligorically correct

Brexit and the skirting of international law

‘Brexit’ has been law since 1 January 2021, but there have been increasing prima facie breaches of Britain’s duties under both local and international law. Duncan Grehan reminds us that the CJEU has jurisdiction to determine any alleged breach of the Withdrawal Agreement – which is subject to the laws of the EU.

The sincere observance by all state parties of their international treaty duties determines their reputation. After World War 1, the Versailles Treaty and its protocol, the Covenant of the League of Nations, both effective from 10 January 1922, had short lives, as their functions and objectives of security and peace by diplomacy became redundant.

Protocoligorically correct

Protocoligorically correct

The 1946 UN Charter, as World War 2 ended, however, recited its clear purpose – “to save succeeding generations from the scourge of war” – and the consequential need for sincere cooperation and good faith by its parties. Article 26 of the Vienna Convention on the Law of Treaties 1969 provides:

“Every treaty in force is binding upon the parties to it and must be performed by them in good faith.” Article 27 states: “A party may not invoke the provisions of its internal law as justification for its failure to perform a treaty.” Non-compliance is a breach of the rule of law.

International and internal

The disorderly implementation of the Brexit treaty, formally the Withdrawal Agreement, is causing legal analysis of conflicts between international treaty duties and internal law.

Following the referendum on 26 June 2016, the Westminster government gave its Brexit notice to the EU per article 50 of the Treaty on European Union, which requires it to perform an “orderly withdrawal”. Following lengthy negotiations, the terms of the agreement were agreed on 19 October 2019.

The agreement included the Protocol on Ireland and Northern Ireland (and similar protocols for Cyprus and Malta). Both were transposed into UK domestic law (by the European Union (Withdrawal) Act 2018) by royal assent on 23 January 2020, and the Withdrawal Agreement was ratified on 29 January 2020, but allowing for a ‘transition period’ ending on 31 December 2020.

Brexit has been UK law since 1 January 2021. Agreed by its domestic law, the Withdrawal Agreement, and the Northern Ireland Protocol is that Northern Ireland shall remain in the EU Single Market for the life of the protocol, which will die on 1 January 2025, unless extended for a further four or eight years.

Extension requires “democratic consent” by a majority of the MLAs “present and voting” in the Northern Ireland Assembly. Some 52 of its 90 current elected MLAs do want the protocol extension. 

Prima facie breaches

There are increasing prima facie breaches of the UK’s duties under local and international law. Outstanding are delays and non-cooperation in implementation of the law agreed by Brexit, and by the increasing number of unforeseen unilateral measures taken by the UK Government and its executive – contrary to the Withdrawal Agreement, without prior consultation and the prior consent of the EU.

Such measures include the continuing extension of the transition period (now by over two-and-a-half years), despite the fact that it had been agreed as ending on 31 December 2020.

Further examples include the failure to apply many EU laws (in breach of article 12(1) of the Northern Ireland Protocol, which also lists many applicable EU laws in its Annex 5), as it particularly agreed, so as to honour and keep secure the EU legal standards for manufactured goods and agricultural goods entering the EU through its Northern Ireland back door. This failure is thereby jeopardising the EU’s integrity.

The UK has not developed nor supplied, on any cooperative basis, entry-and-exit security technology, nor adequate regular hard and soft data on the movement of such goods, as it had agreed to do. It proposes, instead, to do so at some time. It awaits the EU’s agreement to alter its Withdrawal Agreement duties, many of which it has not implemented.

The UK government unilaterally announced its general idea to fulfil its Withdrawal Agreement duty to carry out Irish Sea border controls by self-regulation and self-certification, whereby its ‘trusted traders’ would enter the EU Single Market in Northern Ireland, simply by using drive-through ‘green lanes’ and ‘red customs lanes’ at its ports.

Such a self-centred system opens the back-door risk of illegal-goods movement, smuggling, breaches of EU internal-market standards and its harmonised movement controls, and a need for a hard border between Northern Ireland and the rest of Ireland.

This one-sided approach threatens non-compliance with Britain’s fundamental international-treaty duties under the Withdrawal Agreement, and also under the Belfast/Good Friday Agreement 1998, by which it agreed no hard border between Northern Ireland and Ireland.

The former endorses its committal in the latter “to protect the North-South cooperation and its guarantee of avoiding a hard border, including any physical infrastructure or related checks and controls”.

The on-record attitude of the UK Government to the Northern Ireland Protocol was published on 12 May 2020 in what it calls its ‘Command Paper’.

It acknowledged, even then: “Self-evidently, goods being sent away from the Single Market cannot create a back door into it; and any such goods subsequently leaving the UK would be subject to both exit and entry checks anyway en route to their new destination.”

Unilateral changes

The new Northern Ireland Protocol Bill, without prior consent, notice, or any assistance first being sought from its good friends in the EU, was introduced to the House of Commons on 13 June 2022 and unilaterally scraps the Northern Ireland Protocol duties of the UK.

Rather than complying with what it has agreed in the Withdrawal Agreement and the protocol – namely that UK law would be different for that part of the UK that is Northern Ireland, and which should now have a customs and other controls border at its ports to respect EU integrity – section 1 of its bill “provides that enactments, including the Union with Ireland Act 1800 and the Act of Union (Ireland) Act 1800, are not to be affected by the Northern Ireland Protocol that does not have effect in the United Kingdom”.

This bill seeks to counteract the March 2022 judgment of the Court of Appeal of Northern Ireland in Allister and Ors (before its appeal to the Supreme Court has been decided), in which it is held that the Withdrawal Agreement and the protocol and the 2018 act implementing both into UK law “prevail over any previous historic UK primary constitutional legislation, especially the Act of Union 1800”.

In Allister, many issues of UK law are clarified, and many are under appeal. As noted above, international customary and written laws in treaties and conventions are binding on all state parties by their ratification, and as expressly provided in treaties like the Treaty on the Functioning of the European Union, the European Convention on Human Rights, and the Vienna Convention.

UK law offers less accessibility to certainty, especially in relation to its duties to comply with the rule of law. This is not assisted by its indistinct, unwritten constitution and the status of its primary constitutional legislation, and how this is so categorised. Lady Justice Keegan stated (paragraph 123 in Allister):

“Parliament may place limits upon its own sovereignty by virtue of some Acts of Parliament, such as the European Communities Act 1972, and the Human Rights Act 1998. However, there has not been a court case where judges in the UK have ruled that an Act of Parliament is contrary to the rule of law and therefore unconstitutional.”

This is contradicted by article 27 of the Vienna Convention, by which the rule of law cannot be revoked or overridden by domestic legislation.

The Allister case alleged, among other things, that Brexit was unconstitutional because it introduced discrimination for those traders and persons in Northern Ireland in conflict with their equality rights as UK subjects.

In particular, it claimed it was a breach of their constitutional right as provided, on the historic creation of the UK, in article VI of the Act of Union 1800, which provides “that in all treaties made by His Majesty, his Heirs, and successors, with any foreign power, His Majesty’s subjects of Ireland shall have the same privileges, and be on the same footing, as His Majesty’s subjects of Great Britain”.

Keegan LCJ dismissed the plaintiff’s claim, explaining: “The more general words of the Act of Union 1800, written 200-plus years ago in an entirely different economic and political era, could not override the clear specific will of Parliament, as expressed through the Withdrawal Agreement and protocol, in the context of the modern constitutional arrangements for Northern Ireland.”

So, this dicta overturns the maxim ‘communis error facit ius’, and this leads to the open questions around justiciability, judicial sovereignty, and parliamentary sovereignty – and whether they are defined by the domestic laws of the UK.

Justiciability and sovereignty

Keegan LCJ, in her obiter dicta, found that the legal term ‘prerogation’ effectively fetters ‘justiciability’:

“Prerogative powers, such as those relating to the creation of treaties, the defence of the realm, the prerogative of mercy, the grant of honours, the dissolution of parliament, and the appointment of ministers as well as others, are not, I think, susceptible to judicial review because their nature and subject matter is such as not to be amenable to the judicial process.

“The courts are not the place wherein to determine whether a treaty should be concluded or the armed forces disposed in a particular manner, or parliament dissolved on one date rather than another.”

She explained in her judgment that, while parliament can fetter its own sovereignty (by a statute like the European Communities Act 1972), it cannot fetter the sovereignty of its successors.

Can judicial sovereignty be fettered by common-law precedent judgements? Again, this is uncertain, as there are many types of these: an original precedent creates and applies a new rule; a declaratory one applies an existing one; an authoritative one is binding; but a persuasive one is not, although worthy of consideration.

Therefore, both in UK law and the laws of Ireland, the maxim ‘stare decisis’ applies conditionally. Judicial sovereignty is not absolute and, while it can permit and result in statute law or ministerial orders being found by the court to be illegal, new statute laws and orders can be subsequently made.

Britain has not yet seen UK statute laws and orders that do not comply with the rule of law being found by its court of final appeal to be illegal. New precedent decisions creating new law and overturning old ones can also subsequently be made.

Under the laws of Ireland (although the Constitution states “the decision of the Supreme Court shall in all cases be final and conclusive”), the commentary is that a court is not bound to perpetuate an error of law in a previous decision of court, or which is “not in harmony with modern legal values” (Kelly, p537). Communis error facit ius applies, and laws can be changed if wrong.

Safeguard measures

Perhaps this is why the Withdrawal Agreement and protocol provide so-called ‘safeguard measures’ that permit both or either the UK and/or the EU to unilaterally take such measures. These treaty provisions permit both the EU and the UK to take unilateral measures without the prior consent of both parties if the complex conditions to such permission are interpreted by the CJEU as having been first fulfilled.

Article 16(1) of the Northern Ireland Protocol will be subject to interpretation. It is unclear yet whether interpretation is to be by a strict use and application of its words, or by identifying and applying the underlying purpose of those selected legislative words.

Keegan LCJ referred to the protocol as “a dense and complicated instrument” (paragraph 136). Its article 16(1) says such ‘unilateral measures’ “shall be restricted with regard to their scope and duration to what is strictly necessary in order to remedy the situation”.

What that may mean depends on the reason given for the invocation of such measures. First off, there must be justifying proof, given that the grounds for their invocation are that it is the (long-awaited, full) application of the protocol that triggers the right to activate safeguard measures. The protocol has, so far, yet to be fully and properly activated. Implementation of its terms has been delayed.

Article 16(1) also names only two grounds sufficient to satisfy the right to exercise unilateral measures, specifically “serious economic, societal or environmental difficulties that are liable to persist”,  or “diversion of trade”. But those grounds can only apply “if the application of this protocol leads to” them happening.

The second one appears an easier-argued ground. Diversion of trade from the UK internal market because of wide tariff- and control-free-movement-rights within the 27 states of the EU was always foreseeable.

Since the May 2020 ‘Command Paper’ – which stated that 57% of the exports of goods from Northern Ireland were to the UK internal market – much has changed, and there has been a huge increase in its exports to the EU via Ireland because the UK’s legal duty to control the origins and standards of such export goods is being exercised with lenience or is entirely absent.

National-law measures

Again, article 27 of the Vienna Convention states that no party can invoke its internal laws as justification for “its failure to perform a treaty”.

In the Northern Ireland Protocol Bill, introduced on 13 June 2022, the protocol’s article 16(1) complex trigger test is unilaterally simplified to a subjective test at the discretion of an authorised minister. The justification threshold for the article 16(1) second ground (diversion of trade) to kick in is low, when seen subjectively and locally by a NI Assembly unionist minister.

Delay in this bill – which effectively scraps the Northern Ireland Protocol, and would not perform the protocol, and would block its Withdrawal Agreement treaty duties becoming law – is certain to continue because of the termination of Boris Johnson’s role as prime minister pending UK general elections; the passing of the bill through the Houses; and the pending decision of the Supreme Court on the appeal against the concurring judgment of the three-judge court delivered on 13 March 2022 by Keegan LCJ.

The protocol ceases if the NI Assembly is not reconstituted before the protocol extension deadline on 31 December 2024, and if the protocol is not extended for another four years by the “democratic consent” of “cross-community” elected members who are “present and voting” in the assembly.

The UK government appears to be using delay and this requirement to see the protocol expire without it ever having been implemented.

The orderly withdrawal from the EU required by article 50 of the Withdrawal Agreement has been dishonoured. It was to be honoured, too, by its contemporary Trade and Cooperation Agreement (TCA), and by the Joint Declaration of the EU and UK on future financial regulation and cooperation.

On 23 June 2022, the House of Lords’ European Affairs Committee reported: “Under the UK-EU Joint Declaration, the memorandum of understanding (MoU) was due to be agreed by March 2021. Although technical negotiations did conclude on 26 March 2021, over a year later, the MoU has still not been signed or entered into force.”

It also reports: “The committee regrets the fact that the UK-EU MoU on regulatory cooperation is still not in place, despite technical negotiations having concluded more than a year ago. The committee notes the widespread view that the MoU has become a casualty of wider tensions between the parties, particularly regarding the implementation of the protocol on Ireland/Northern Ireland.”

Good faith

The duties of the rule of law require orderly implementation, sincere cooperation, and good faith. No UK statute law has yet ever been held by the UK court of final appeal (in an authoritative precedent decision) to be in breach of the rule of law and, therefore, unconstitutional.

The Withdrawal Agreement – an international treaty between the UK and EU (and its 27 member states) – and its four-year-term Northern Ireland Protocol, ratified by the UK on 29 January 2020 (two-and-a-half years ago), provides in its agreed article 5: “The Union and the United Kingdom shall, in full mutual respect and good faith, assist each other in carrying out tasks which flow from this agreement … This article is without prejudice to the application of Union law pursuant to this agreement, in particular the principle of sincere cooperation.”

The Withdrawal Agreement is subject to the laws of the EU, and therefore the CJEU has jurisdiction to determine any alleged breach of it, or issue to which the agreement may give rise. 

Look it up




  • Hogan and Whyte (1994), JM Kelly: The Irish Constitution (third edition) (Butterworths)
  • House of Lords’ European Affairs Committee report (The UK-EU Relationship in Financial Services, 23 June 2022)
  • Joint declaration of the EU and UK on future financial regulation and cooperation

Duncan Grehan is a member of the Law Society’s EU and International Affairs Committee.  

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