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May's Draft Brexit Deal: A True Challenge to UK Sovereignty?

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About The Author

Michael Lane (Guest Contributor)

Michael is a current International LLM student, and Visiting Lecturer in Public Law, at Birmingham City University. He is looking to undertake his PhD in September 2019, focusing on the UN's Universal Periodic Review. When he's not researching or teaching, he spends his time gaming or indulging in his music.


I believe if we were to go back to the European Union and say: Well people didn't like that deal, can we have another one? ... I don't think they're going to come to us and say: We'll give you a better deal.

Theresa May

Whatever your political position on the issue, Brexit has certainly sparked everyone's interests in recent weeks, with Theresa May confirming that a deal has been reached with the EU on the UK's withdrawal. However, one would be mistaken to think this meant that the Brexit saga was over, and that we could all sit back and claim our blue passports and commemorative silverware. The fact is - whatever you think about the deal May has reached - the UK's political and legal fate is far from established.

While this article may draw on some aspects of the proposed deal, it will not – because of the lack of clarity and certainty regarding certain aspects – seek to analyse all of it. This article simply seeks to understand a key policy of the deal that nobody - leave or remain - should back because it fundamentally risks UK legal sovereignty. Before delving into what this means, it is worth briefly reflecting on what has happened in the last few weeks.

What Has Happened So Far

After two years of negotiations, May returned to the UK on Wednesday with a draft Brexit deal - the text of which can be found here. The document is almost 600 pages long, and attempts to clarify various aspects of the UK's exit, inter alia: future customs arrangements, the Northern Ireland/Ireland border, fishing/agricultural policies. More can be read about the specifics of the proposed plans here.

Following this, May attempted to rally the support of her cabinet, in order to establish a collective agreement on the draft deal, before taking it to be debated in Parliament. Despite claiming that the cabinet were in such agreement, several ministers proceeded to resign the following day. As such, it is thus rather difficult to suggest that there was, in reality, a collective agreement.

The minister responsible for the Department for Exiting the European Union, Dominic Raab, was the first to resign, claiming that the agreement had "fatal flaws". Similar comments had been made by the Democratic Unionists Party - the very party that May is relying on for her Parliamentary majority. In fact, May has been criticised from all angles.

In particular, this article proposes that for once, both 'leave' and 'remain' voters should be in agreeance that what May has negotiated is not in the UK's best interests. In particular, the proposed solution to the Northern Ireland/Republic of Ireland border problem raises not only political questions for those respective states, but questions of a fundamentally constitutional and legal nature that will impact the rest of the UK.

The Republic of Ireland (ROI)/Northern Ireland (NI) Border 'Backstop' Plan

The Good Friday Agreement, struck between NI and the ROI, signalled the end to the conflict (often referred to as ‘the troubles’) between the two states that had raged on for decades by attempting to break down the political and physical barriers that separated them – in particular, the border. Therefore, one of the issues for May (and for the EU) to resolve in Brexit negotiations is to ensure that no hard border (for goods or persons) is placed between NI and the ROI. To do otherwise could signal a reversal of the peace established in the Good Friday Agreement, and potentially reignite tensions between NI and the ROI. As such, it is easy to understand why it is almost unanimously agreed that a hard border between NI and the ROI is a deeply undesirable idea.

May’s draft agreement therefore proposes, under Article 126, a 'transition period', whereby the UK will continue to participate in EU free movement until December 2020. The purpose of this transition time is to decide on the specifics of a UK-EU trade deal that, amongst other things, prevents the aforementioned hard border between NI and the ROI for goods and persons.

If a comprehensive trade deal cannot be reached between the UK and the EU by the end of this transition period (December 2020), the UK will form part of a 'temporary customs territory' with the EU - thus still preventing the need for any border checks for goods or persons. On the face of it, the deal arguably solves this issue of a hard border because, in any event, the UK will at the very least remain part of 'a customs union' with the EU. However, per Article 20 of the Protocol of Northern Ireland in the Draft Agreement, the only way this temporary arrangement can end is if "the Union and the United Kingdom decide jointly" (herein the "joint agreement" clause).

Thus, despite an apparent solution to the ROI/NI border problem, this plan actually creates an added layer of uncertainty which has sparked outrage from both prominent Remainers and Leavers. The focus of this article, and the issue identified by many, is this idea of 'joint agreement':

Oft-expressed concerns surrounding this 'joint agreement' clause include:

How long will this temporary union last?

Does this not mean that we are essentially not leaving the EU at all?

What if a hard border is inevitable and we are just delaying the issue?

More relevantly (and worryingly):

If the temporary customs territory comes into effect, and we cannot leave without joint agreement with the EU, are we not basically legally and politically bound to the territory until the EU decides otherwise?

This last point carries immense weight. Prominent leavers, throughout the Brexit process, have argued that leaving the EU will 'restore UK sovereignty' or allow the UK to 'take back our law-making power'. However, the 'joint agreement' clause appears to do quite the opposite, and actually puts UK sovereignty at risk. To demonstrate why the 'joint agreement' issue risks UK sovereignty, it may be worth briefly exploring the topic of UK sovereignty and EU membership.

EU Membership and State Sovereignty

The UK, and all other member states, voluntarily sacrifice an element of their legal sovereignty to the EU in return for membership, allowing the EU to legislate on matters that thereby benefit all 28 member states. For instance, the aforementioned frictionless trade system free from tariffs, customs duties and quantitative restrictions. The key to this membership is its voluntary nature - the UK, and other states, have chosen to be a member of the EU, and therefore accept the inevitable loss of legal sovereignty as the price to pay for these benefits attained through EU membership.

In the UK, the voluntary nature of EU membership is demonstrated by the European Communities Act 1972 (ECA 1972), which gives (at a basic level) EU law automatic effect in the UK. As famously expressed by Lord Bridge in the case of R v Secretary of State for Transport ex parte Factortame Ltd [1990]:

[W]hatever limitation of its sovereignty Parliament accepted when it enacted the European Communities Act 1972 was entirely voluntary.

Because the ECA 1972 is UK legislation, passed by the UK Parliament, the UK has always retained the legal entitlement to stop EU law taking effect in the UK. Therefore, legally, EU membership never really destroyed or otherwise permanently relinquished UK sovereignty. The UK has voluntarily and temporarily given away that sovereignty to the EU and therefore, by leaving the EU, the UK's sovereignty should theoretically be restored.

Hypothetically, it follows that: if the UK was an involuntary member of the EU, or perhaps just a part of it, then the UK could no longer be said to be wholly sovereign. A state's ability to act voluntarily in any given sense is tantamount to its sovereignty.

Conclusion: The Issue

The issue is clear: this hypothetical situation could quickly become a reality. The 'joint agreement' clause in the draft deal, interpreted literally, appears to solve the ROI/NI border issue, but could simultaneously remove the UK's ability to be a voluntary member of a customs territory with the EU.

To reiterate an earlier point, if the UK fails to reach a deal by the end of the transition period in 2020, it will formally leave the EU, and will therefore no longer benefit from the customs union.  As per the draft agreement, a 'temporary customs territory' will take effect immediately after the transition to prevent the ROI/NI hard border.

As such, whilst the substance of the UK & EU's customs arrangement might remain similar, the fact is: the UK could become locked into a customs arrangement of which membership can only be renounced by execution of the 'joint agreement' clause - in essence, the EU retains a say as to whether we stay or leave the arrangement. The UK would therefore go from being a voluntary member of an EU's customs union, to being an involuntary member of a customs union.

The inescapable conclusion of this is that: because the ability of the UK to act voluntarily is inextricably linked to its claim to sovereignty, involuntary membership of a customs union (of any description) with the EU would appear to truly diminish UK sovereignty.

The backstop plan can therefore be viewed as a massive "lets deal with it later" clause, which ignores a fundamental constitutional and legal quandary. It risks locking the UK into a legal customs arrangement that undermines its ability to act voluntarily, and therefore its sovereignty. That, regardless of our individual political outlooks, is something we should all be able to agree is not in the interests of the UK post-Brexit.

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Tagged: Brexit, European Union, Parliamentary & Elections, Public Law

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