The GFA sets out the strict parameters of the choice: the people of the North can decide to remain in the union with Britain or choose to become part of a reunified Ireland. If the North opts for the latter, the people of the South can agree to accept that decision and to make the necessary constitutional and other arrangements required to make it happen. The vote in each jurisdiction is decided on a simple majority of 50 plus 1 per cent of those who vote. Under the terms of the Agreement, and the UK’s Northern Ireland Act 1998, which gave it legislative effect, the decision on when to call a referendum rests with the secretary of state for Northern Ireland. The Act states that the secretary of state will direct the holding of a poll ‘when it appears likely to him [sic] 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.’

In this respect, the GFA sets out a pathway for unity based on the concept that the people of Ireland, separately but concurrently, should decide their own future. It gives the power to the British government to decide a date for a referendum, while it also provides for a regular poll on unity to take place at a frequency of not more than every seven years. In other words, if the prospect of unity is rejected on the first occasion, voters can be asked to consider it every seven years until the proposal is accepted.

The GFA also envisaged a situation where devolved political structures, agreed during the negotiations for the peace agreement in 1998, could continue after a vote for unity. Thus, the power-sharing executive and the elected assembly that sits at Stormont in Belfast could continue to function after any such vote as a form of local or devolved administration, or for a transitional period, in a united Ireland. Similarly, the British–Irish Intergovernmental Conference (BIIGC), which is separate to and independent of the assembly and other structures of the GFA, could also continue to function as a mechanism for continuing co-operation of the two sovereign governments after a vote for unity.

The GFA does not prescribe the details of the new constitutional arrangements or political structures that would be put in place following a vote for unity. Neither does it, nor could it, specify how the post-unification society would deliver the basic requirements of its citizens in relation to health, education, transport or other public service provision, or on the range of policies, laws, rules and procedures that make for a functioning democratic society.

Instead, following a vote for unification, it will be left to the government of Ireland – which will have sovereignty after the referendum – in consultation with its citizens, to decide what should be done to ensure that the new, unified island maintains the confidence of its citizens in the institutions and laws of the new state. This also applies to the issues that would need to be addressed if voters in the North reject the proposal for a united Ireland and seek to remain part of the UK; then the responsibility would lie with the British government to oversee any required changes in its administration.

Research is continuing on the timing and form of the referendums, as well as on the potential constitutional rearrangements, political structures and policies that might be best suited to accommodate a vote by a majority of people in the North to become part of a united Ireland. However, it is agreed by all of those engaged in this research that the people who are being asked to exercise their right to self-determination should be informed of the constitutional, economic, political and social consequences in advance of the referendums. Some academics have asserted that, while the referendums must be held concurrently, that does not mean simultaneously, nor on the same day, as occurred when the GFA was endorsed by voters, North and South, on 25 May 1998.

On that occasion, voters in the North were asked to agree to the proposals contained within the proposed Agreement (they had received copies of the document in the weeks previous). Voters in the South were also asked to agree to the removal of Articles 2 and 3 of the Irish Constitution, which contained a territorial claim over Northern Ireland, and to replace them with a provision that only a decision reflecting the wish of a majority of voters in the North could end the union with Britain. This principle of consent was balanced by the right to self-determination given to the people of Ireland through concurrent votes, North and South.

Those entitled to vote will be determined by the two governments and some observers believe that the franchise could be extended, as was the case in the 2014 Scottish referendum on independence, to allow all those over the age of 16, and possibly Irish citizens living in other jurisdictions, to participate, given the historic significance of the poll for younger and future generations. Any such extension could require a constitutional amendment in the South in advance of the referendum on unity.

It is evident that the optimum way to a seamless or, at least, less disruptive transition to a unified Ireland is to ensure that voters have a reasonably clear picture of the constitutional arrangements and political structures that will emerge if they choose the unity option. For this reason, it would seem obvious that voters should know in advance what changes are required to be made to the Irish Constitution to facilitate unity, or indeed whether an entirely new one should be constructed. Voters should know in advance what guarantees will be put in place to ensure that the identity of those who will remain British citizens in a united Ireland is protected. Similarly, the GFA anticipated a bill of rights for Northern Ireland, which has not yet been introduced, which could then apply in any new constitutional arrangement.

While some will argue for a minimalist approach to constitutional change, there are others in both parts of the island in political, academic and legal circles, and in civic society, who see the referendums as an opportunity to continue, or accelerate, a more transformative process of social and political change, post-unification. The GFA envisaged such progress to a modern, pluralist society when it required the sovereign government, following unity, to exercise power on the basis of the principles of equality and parity of esteem of both communities. In order for this ambition to be realised, detailed and fact-based research over a significant period of time, and across civic and political society and opinion on the island, is required. Consideration should also be given to how existing rights can be expanded for each citizen, including those from all ethnic, migrant and other minority communities.

As the entire territory of a united Ireland will immediately become part of the EU, without any change to the Treaty of Rome, the new sovereign government will also be a party to the European Convention of Human Rights (ECHR) and the European Court of Justice (ECJ). These and other EU laws and institutions will underpin the human rights, equality and other legislative protections of citizens of the new, united Ireland. In this regard, the citizens of the new state will come under the legislative remit of both the sovereign government of Ireland and of the EU.

When the assembly and executive collapsed the following year, in early March 2017, following the decision by Sinn Féin (SF) to pull out of the power-sharing arrangements, disaffection among nationalists escalated. Their ability to influence political decision making in the North diminished and their future outside the EU was being determined exclusively by the British government and the Westminster parliament.

The collapse of the institutions came amid recriminations over the involvement of senior Democratic Unionist Party (DUP) ministers in a scandal surrounding huge payments to its supporters from a Renewable Heating Incentive (RHI) scheme introduced by the British government. This followed an earlier controversy over the sale of properties in the North controlled by the National Asset Management Agency, an Irish government body set up to deal with the bad debts of the main banks in the South following the financial crash of 2008/09. The controversy implicated and politically damaged DUP leader and First Minister Peter Robinson, as well as some of his party colleagues in the NI Executive, and led to criminal charges against other individuals with close links to the organisation.

Nationalist and republican concerns were exacerbated when the DUP entered into a confidence and supply agreement with the British government and Conservative Party leader Theresa May, a few months after the collapse of the Stormont institutions, deepening a suspicion that the largest unionist party had little or no interest in restoring the devolved administration. Given that they were holding the balance of power at Westminster, and their open support for a hard Brexit, the DUP MPs were under no urgency to continue sharing power with SF and other parties in the North.

In the absence of political institutions, and amid growing fears about the impact of a no-deal or hard Brexit on the North, fresh voices emerged from within the nationalist and republican community about their lack of political representation and the uncertain future facing them and their children as Irish citizens. As a reflection of these concerns, Ireland’s Future (IF), a non-party initiative of civic nationalists, emerged with an open letter sent by email to Taoiseach Leo Varadkar, on 8 December 2017 and published in the Irish News three days later. The letter was signed by almost 200 people, including prominent members of the business, academic, legal, arts and sporting communities across the North. It described the political pact between the DUP and the Conservative Party as ‘a grave threat to political progress’. It noted the ‘concerted undermining of the political institutions’ and said the political crisis in the North was due to the failure of both governments to defend the Good Friday, Stormont House and St Andrews agreements made over the previous two decades:

On the day the letter was delivered, 8 December, Varadkar, made an official statement with a commitment to the nationalist people in the North that their interests were being protected during the negotiations with Britain on its departure from the EU: ‘Your birth right as Irish citizens, and therefore as EU citizens, will be protected. There will be no hard border on our island. You will never again be left behind by an Irish government.’ Just weeks earlier, on 23 November, Tánaiste and Minister for Foreign Affairs, Simon Coveney, told the Oireachtas Committee on the Good Friday Agreement, that he ‘would like to see a united Ireland in my lifetime, and, if possible, in my political lifetime’.

Both Irish government leaders were responding to the outbreak of anger among nationalists in the North at the absence of political representation since the collapse of the institutions, the increasing prospect of a no-deal Brexit, which could see the reintroduction of a hard border in Ireland, and the influence of the DUP at Westminster where it held the balance of power.

In return for the support of the DUP’s 10 MPs, the May administration, it appeared, was prepared to jettison its responsibilities to advance significant provisions in the GFA in relation to human rights and legacy issues arising from the conflict, and on the promise of Irish language legislation and other commitments the British government had made since 1998.

After lengthy negotiations brokered by Coveney and Secretary of State for Northern Ireland Karen Bradley, a package of proposals that could have restored the power-sharing executive was rejected at the eleventh hour by DUP leader Arlene Foster in early February 2018. She rejected claims from SF that an agreement had been reached on contentious issues such as an Irish language act, marriage equality and a proposed bill of rights for NI, but it was widely suspected that the plug has been pulled on a deal at the insistence of the DUP MPs at Westminster.

The failure of this latest attempt to restore the institutions re-energised the campaign by IF, which set about widening its appeal across the nationalist and wider non-unionist community and refining its message. It found a growing audience, including among ‘soft unionists’ and people of no affiliation to either of the main political traditions. Many of these had voted against Brexit in 2016 and were deeply concerned about the direction the process of withdrawal from the EU was taking and its longer-term implications for their families and communities. IF reflected these concerns and also tapped into a deepening anxiety across the communities arising from the nature of the Brexit deal Theresa May was promoting and her stated intention to remove protections provided to Irish citizens in the North through the GFA and the ECHR.

Niall Murphy, a founding member of the group and a solicitor with Belfast firm KRW Law, represented clients seeking redress for suffering they endured at the hands of the British state, its army and police during the years of conflict. Among these were victims of collusion between the security forces and loyalist paramilitaries, including those killed and injured by an Ulster Defence Association (UDA) gang at Sean Graham bookmakers shop on the Ormeau Road, in Belfast in 1992, and those shot dead in an Ulster Volunteer Force (UVF) attack on O’Toole’s pub in Loughinisland, County Down, in 1994. As a director of the board of the human rights group Relatives for Justice, Murphy was also concerned by the failure of the British government to address the legacy of official state collusion with loyalist paramilitaries and unresolved and illegal killings by British security forces. As a solicitor, he was particularly angered by the prime minister’s proposals to remove the protections and legal recourse available to his clients, including a number from the loyalist community, from the ECHR.

The next major initiative of the embryonic movement was planned to coincide with May’s attempt to push through her best attempt at a Withdrawal Agreement in the Westminster parliament in Autumn 2018. IF decided to convene a major gathering of civic nationalism, along with as many unionists and those of other political persuasions as were willing to attend, to demonstrate their opposition to May’s proposals and the continued absence of political representation within the North since the collapse of the power-sharing institutions. In response to Coveney’s and Varadkar’s statements of support for nationalists in the North, Murphy and the small group of activists that led the IF initiative issued an invitation to Coveney to open, and to Varadkar to close the event: a conference to be held in Belfast’s Waterfront Hall in October 2018. In the run up to the conference, discussions were held in Belfast with two officials of the Department of Foreign Affairs, Eamon Molloy and Fergal Mythen, who passed on the request to their colleagues in Dublin.

In reply, Coveney and his senior department officials requested that the conference be postponed given the sensitivity of the Brexit discussions between the British government and the EU and their concern that such an event attended by senior politicians, including the Taoiseach and Tánaiste, from Dublin would upset unionists. The Irish government officials argued that the unionists were already complaining about the ‘backstop’ envisaged in the deal negotiated by May, which would keep the North within the EU customs and trade area following Brexit. The compromise was designed to maintain a frictionless border in Ireland until alternative customs and other trading arrangements could be agreed in a final ‘divorce settlement’ and following a two-year transition period.

The Withdrawal Agreement and the Irish backstop would see the UK staying in a customs union with the EU while the North would also remain aligned with the EU single market for the purposes of certain rules and regulations. The DUP members at Westminster joined in the chorus of Brexiteers denouncing the perceived surrender of sovereignty by the prime minister marking the beginning of the end of the unhappy relationship between the party’s MPs and Theresa May. On the day she travelled to Brussels to close the deal in late November 2018, May’s main rival in the party, Boris Johnson, went to Belfast where he told cheering delegates at the DUP party conference that ‘no British government could or should’ agree to a border in the Irish Sea. ‘If you read the Withdrawal Agreement,’ Johnson said, ‘you can see that we are witnessing the birth of a new country called UK(NI) or Ukni. Ukni is no longer exclusively ruled by London or Stormont. Ukni is in large part to be ruled by Brussels.’ He warned that the backstop would separate Northern Ireland from the UK and repeated an earlier suggestion he had made for a bridge to be built between Scotland and Northern Ireland. ‘We need to junk the backstop,’ he told the receptive audience of DUP members.

The IF team acceded to Coveney’s request to postpone the conference and instead published a second letter in the Irish News to the Taoiseach, reminding him of the commitment he had made to nationalists in the North in December 2017. They warned, again, of the dangers posed by a hard deal Brexit and of the resulting suppression of rights available to Irish citizens north of the border: