Challenging the Belfast Agreement: how Brexit is impacting Northern Ireland's constitutional future

Published: 4 February 2020

The 1998 Belfast Agreement included a three-stranded formula aiming to institutionalise contested relationships within Northern Ireland, between Northern Ireland and Ireland and between Northern Ireland and the UK. Mary Murphy examines the ways Brexit has challenged the three strands of this agreement. 

The 1998 Belfast Agreement included a three-stranded formula which aimed to normalise and institutionalise contested relationships within Northern Ireland, between Northern Ireland and Ireland, and between the two islands. The foundations of all three strands have been challenged by the unfolding Brexit process.  

Brexit and Strand 1: Internal Relations in Northern Ireland 

Although the Democratic Unionist Party (DUP) was the only party in Northern Ireland to support the Leave position during the 2016 Brexit referendum campaign, a constitutional cleavage began to emerge thereafter as all swathes of political unionism moved to support the UK exit from the EU. Nationalist parties and the non-aligned Alliance Party, by contrast, reinforced their opposition to Brexit and called for Special Status deal for Northern Ireland. 

Having been little more than a footnote during the wider UK referendum campaign, Northern Ireland was front and centre during Phase 1 of the Brexit negotiations. Although the UK and the EU both sought to construct an exit strategy which would prevent a hard border on the island of Ireland, the issue stoked the constitutional question. DUP opposition to the backstop negotiated by Theresa May’s government was linked to a perception that such provisions potentially lay the groundwork for future Irish unity. For all shades of unionism, Prime Minister Johnson’s Brexit deal, which treats Northern Ireland differently to the rest of the UK and introduces checks at the Irish Sea border on goods moving from Britain to Northern Ireland, is guilty of the same offence. The notion that the deal constructs some of the economic infrastructure associated with a future united Ireland has aroused pronounced unionist and loyalist hostility against what has been labelled the Prime Minister’s Betrayal Act.  

Nationalist opposition is based on an outright rejection of Northern Ireland being forced to leave the EU, despite the region’s vote for Remain. They also fear the potentially dire economic and political consequences that Brexit is perceived to entail. 

In removing the EU as a backdrop for the accommodation of differing political aspirations, Brexit has created new dividing lines in Northern Ireland and widened the political gap between unionism and nationalism. 

Brexit and Strand 2: North-South Relations 

Brexit undermines the supporting framework which helped to sustain cross-border relations on the island of Ireland. The remit and operation of cross-border institutions created by the Belfast Agreement (most especially the Special EU Programmes Body) are challenged by Brexit. The impact is particularly unsettling for nationalists because the recognition and protection of their identity is linked to cross-border institutional innovations. There is some awareness that North-South institutions must be protected, but little detail in relation to how they might adapt to a post-Brexit environment. 

The Brexit process has also sullied relations between unionists and the Irish government. Unionist insecurities have been heightened by the Irish government’s approach to Brexit which is seen as privileging an open border on the island of Ireland at the expense of some hardening of the border between Northern Ireland and the rest of the UK. 

Brexit and Strand 3: British-Irish Relations 

Brexit has also damaged the British-Irish relationship. The Northern Ireland peace process was built on a shared and agreed British-Irish approach to the process of conflict resolution. Brexit has challenged this bilateral approach. The Irish government’s preference for the softest of Brexits clashed with a vacillating UK position. 

Brexit has also exposed, and perhaps even solidified, the psychological distance between Northern Ireland and the rest of the UK. Polls have revealed that a majority of British voters do not feel a deep constitutional connection to Northern Ireland and would rather Northern Ireland leave the UK in exchange for a good Brexit deal. This apparent British indifference to Northern Ireland further feeds and fuels a sense of betrayal among unionists in Northern Ireland who feel vulnerable to what they view as a duplicitous Irish government, an unsympathetic EU and an undependable UK Prime Minister. 

Brexit and the Totality of Relationships 

The 1998 Belfast Agreement includes a provision for the Secretary of State to call a border poll (a referendum on a united Ireland) in the event that ‘it appears likely to him that a majority of those voting would express a wish that Northern Ireland should cease to be part of the United Kingdom and form part of a united Ireland’ (Annex, Schedule 1).

For now, no Irish or British political party, other than Sinn Féin, is seriously engaged with the unification agenda. Even so, for unionists, the Union is not as solid as it was pre-Brexit. For nationalists, the prospect of Irish unity is not as remote as it was before 2016. Indeed, there has been some mobilisation of civic society to explore the issue of reunification. Brexit has been a key trigger for this unexpected constitutional conversation. 

Brexit comes with many costs and consequences for the island of Ireland. Long-term, however, its legacy and most notable impact may well be how the decision for the UK to leave the EU challenged the three strands of the 1998 Belfast Agreement and precipitated moves towards new British and Irish constitutional futures. 

Read our latest report with UK in a Changing Europe 'Brexit and the Union' discussing some of the issues Brexit presents for the UK's territorial and constitutional future. 

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