Colin Murray: Brexit and the “Constitutional Integrity” of the United Kingdom

Something no Prime Minister could contemplate

The Foreign Office records regarding the Paris Peace Conference of 1919 must be amongst the most regularly requested papers held at the National Archives. One file, FO 608/65, is part of the herculean effort to redraw the map of Europe after the First World War. It recounts the efforts of officials and ministers to work out how to provide Poland with meaningful access to the Baltic. The focus of this attention was the port city of Danzig. The two options before the Council of Ten were to include the city as part of Poland, but place limits on how Poland exercised its national sovereignty over this part of its territory, or to create a “free city”, administered by a League of Nations High Commissioner, which was tied into a customs union with Poland. In late March 1919 Lloyd George expressed the UK’s support for the former option in the Council. Behind the scenes, however, the Foreign Office was preparing the alternate plans for a free city, which Lloyd George backed to decisive effect in April 1919. Concerns that this reversal might destabilise the fledgling Polish state were summarily dismissed.

It is therefore not without irony that a century later the UK, its great power pretensions a little more careworn, finds the shoe very much on the other foot in Brexit negotiations. Theresa May came to Salzburg blustering that the EU’s proposals for Northern Ireland represented a compromise of the UK’s “constitutional integrity” that no British prime minister could contemplate. The UK contemplates imposing such choices upon other countries, but not being confronted with them for itself. As she left Austria in a rage it is a small wonder that the EU has not yet proposed the creation of the Free City of Belfast (and hinterland). This post examines the mantra of constitutional integrity in the era of Brexit.

The Joint Report’s backstop

The EU’s current effort to give legal form to the UK and EU’s agreed position on Northern Ireland in December 2017 is not far removed from the alternate option for Danzig in 1919. The practical effect of its terms is that Northern Ireland will remain part of the UK, but unless a full future agreement or bespoke Northern Ireland arrangements satisfactorily address all issues of North-South cooperation, the Westminster and devolved institutions will be prevented from acting in a way which undermines regulatory ‘alignment’ between Northern Ireland and the EU Single Market (paragraph 49). They will furthermore not be able to act in such a way as to ‘prejudice … the rights, opportunities and identity that come with European Union citizenship’ (paragraph 52).

This position was negotiated on the basis of the Good Friday/Belfast Agreement. This international treaty, approved by a majority of the people of Ireland and Northern Ireland in a 1998 referendum, enjoys a constitutional significance which is only just coming fully into view. The Agreement’s significance as an interpretive tool extends beyond those elements which were incorporated into statute by the Northern Ireland Act 1998. Its acknowledgement of the ‘birthright’ of the people of Northern Ireland to choose their identity as British, or Irish, or both (Section 2, para.1(vi)), for example, was not incorporated into statute. In the de Souza case, however, successive tribunals have reinterpreted the British Nationality Act 1981 in light of the Agreement’s requirements (a Home Office appeal is ongoing).

From the immediate aftermath of the 2016 referendum the UK Government had made commitments that the Agreement would be protected in full. The December 2017 Joint Report saw the EU push the UK Government to put its money where its mouth was. The resultant agreed position on Northern Ireland is based on a recognition that the Agreement ‘must be protected in all its parts, and that this extends to the practical application of the 1998 Agreement on the island of Ireland and to the totality of the relationships set out in the Agreement’ (paragraph 42). Had the UK Government done more ground work for Brexit before triggering Article 50 it would surely have appreciated the extent to which this approach would limit its room for manoeuvre.

Limited wiggle room

Having accepted the broadest possible interpretation of the 1998 Agreement’s terms in the Joint Report, the UK Government belatedly began to appreciate the bind in which it found itself. The post-Chequers’ deal White Paper attempted to brazen the issue out; a free trade area covering goods “would avoid the need for a hard border between Northern Ireland and Ireland, without harming the internal market of the UK – doing so in a way that fully respects the integrity of the EU’s Single Market, Customs Union, and its rules-based framework” (pp.7-8). Saying that the border would be unaffected, however, does not make it so. As the EU has since maintained, this stops far short of the full alignment provided for by the backstop. Chequers provides for a partial alignment, and border checks would remain necessary for the EU to protect the integrity of its Customs Union.

EEA membership or potentially, depending upon its scope, a bespoke Customs Union (as suggested by the UK Labour Party), has the potential to amount to such a fulsome UK-EU relationship post-Brexit as to vitiate the need for the Northern Ireland backstop. Perhaps the most surprising aspect of the latest backstop spat is that Jeremy Corbyn has loudly rejected the possibility of “a border in the Irish Sea”, rather than emphasising Labour’s commitment to ensuring that it would be redundant. Does this position indicate a failure to understand Keir Starmer’s proposals, or suggest that once the debate has been cast in terms of constitutional integrity, no leader of a main party can afford to be painted as unpatriotic? Even if one of these approaches was adopted, extra elements would be required to fully meet the UK’s commitments of December 2017. The people of Northern Ireland will have to retain voting rights in European Parliament elections (a report is due from Ireland’s Constituency Commission which will set out proposals as to how this representation will be managed). And these nascent arrangements are already coming under fire as a threat to the UK’s constitutional integrity.

You do it to yourself… and that’s what really hurts

Theresa May’s increasing talk of the “precious Union” she is seeking to protect from the threat posed by the backstop arrangements is in part a marker of how dependant she has become on DUP votes in Westminster. It is also, however, a smokescreen intended to deflect from the fact that the backstop was not suddenly forced upon the UK Government, but freely accepted as part of the negotiations towards the December 2017 Joint Report. It is not the EU’s fault that, as the (DUP-heavy) Northern Ireland Affairs Select Committee acknowledged in March 2018, the UK Government has not produced any workable proposals for technological fixes which would provide for frictionless trade. Or that the very notion of trade could ever be achieved with as little cross-border friction as the current single market arrangements was a fantasy, and would always bring the supposed backstop to the fore.

Theresa May’s calls for the EU to “evolve” its thinking on the backstop deny the basic fact that the UK has already ceded this territory in the negotiations, and the EU sees no reason to give ground that it has won through its arguments about the logical consequences of the UK’s Good Friday/Belfast Agreement Commitments. “Minimal checks” between Northern Ireland and Great Britain (and the separation of Northern Ireland from post-Brexit UK trade deals) become, for the EU, the price of the UK Government’s insistence on rejecting the EEA option post Brexit. Indeed, for the EU, it is the UK Government’s rejection of the EEA option which stands to impose East-West barriers in the Irish Sea, not the EU’s negotiating position.

Many of those East-West barriers have existed before, on the UK’s own terms. As recently as the 1960s, Northern Ireland drivers had to apply for a Carnet de Passages to bring a motor vehicle from Northern Ireland into Great Britain. Some of these divisions exist today; all of Ireland is, for example, treated as a distinct epidemiological area (as Ian Paisley Sr was quoted as saying, as the DUP pushed for this reorientation to dampen the impact of Foot and Mouth on Northern Ireland’s agriculture, “Our people may be British but our cows are Irish”). And if the land border between Ireland and Northern Ireland remains open for personal travel after Brexit (as the consensus around the Common Travel Area suggests it will), the absence of identity checks on travellers between Northern Ireland and Great Britain is unlikely to outlast the UK Government’s dependence upon the DUP’s votes at Westminster. Shouts of “constitutional integrity” ring hollow.

What happens in Northern Ireland, stays in Northern Ireland?

The Prime Minister’s rhetoric sustains a DUP narrative of Brexit as restoring unabridged “British sovereignty” over Northern Ireland (preserving “the political, constitutional and economic integrity of the United Kingdom”). It is a narrative which is at odds with the majority support in Northern Ireland for remaining within the EU. It is a black-and-white account which many in Northern Ireland find deeply alienating, and which, ironically, contributes to the possibility of a border poll. The less nuanced the conception of national sovereignty that the UK Government advances, the more likely it is to undermine public support in Northern Ireland for the constitutional status quo.

The emotive talk of a “precious Union” and of the UK’s “constitutional integrity”, moreover, neglects the extent to which, as my co-authors and I have recently argued, Northern Ireland has been a constitutional “place apart” since partition in 1922. The Ireland Act 1949 incorporated restrictions on parliamentary sovereignty regarding changes to Northern Ireland’s place in the UK which still exist in modified form. The Anglo-Irish Agreement of 1985 recognised that Ireland had a say in the governance of Northern Ireland, as guarantor of the “minority community” in Northern Ireland (Articles 4(c) and 5(c)). The Good Friday/Belfast Agreement translated this arrangement into a role for Ireland as co-guarantor over the peace process. Northern Ireland remained part of the UK, but it was no longer, as Margaret Thatcher almost said four years before the Anglo-Irish Agreement, “as British as Finchley”. Shades of grey were introduced into the constitutional picture which today support some unique settlement for Northern Ireland as part of Brexit. The UK Government, tied down by Westminster arithmetic, cannot bring itself to acknowledge this constitutional reality, and instead continues to brief against the Irish Government as a meddlesome neighbour. That it is able to do so speaks to how little Northern Ireland’s distinct constitutional settlement is understood at Westminster (perhaps best illustrated by Karen Bradley’s recent unguarded admissions). Nonetheless, if there is to be a Brexit deal, the UK Government will either have to move further towards an EEA position or accept Northern Ireland as a territory in which sovereignty will become increasingly complex and overlapping.

Colin Murray is a Reader in Public Law at Newcastle University.

(Suggested citation: C. Murray, ‘Brexit and the “Constitutional Integrity” of the United Kingdom’, U.K. Const. L. Blog (25th Sept. 2018) (available at