Professor Imelda Maher:

I thank the Chairman and members of the committee for affording me the opportunity to speak today. I have been asked to speak about EU treaty protocols. I sent the briefing notes to the clerk of the committee just before lunch.

I will briefly outline the most relevant protocols in respect of the relationship between Ireland and the UK. The reason for doing this in the context of a discussion of BrExit is that they are primarily concerned with control of migration and borders. Should the United Kingdom chose to leave the EU, the Northern Irish Border would become significant for the EU as it would become an external EU border. This would then raise considerable challenges for the open borders policy between the United Kingdom and Ireland as articulated in the common travel area. There are three protocols of note and another I will mention in passing.

First, Protocol 19 relates to the Schengen acquis. Schengen is an international convention designed to remove internal borders and establish a common external frontier. This means it also establishes common visa, asylum and immigration policies. Implementing measures known as the Schengen acquis were adopted on these policies and these were incorporated into the EU treaties and into EU law by the Amsterdam treaty, which is now part of EU law. There are special rules for Ireland and the UK in regard to Schengen as the only two member states that have not signed the convention. Others such as Bulgaria, Croatia, Cyprus and Romania have signed but are not fully incorporated into it. The relationship between the UK and Ireland and the Schengen provisions is addressed mainly in Protocol 19.

Ireland and the United Kingdom - throughout my address I will refer to Ireland but members should read it as Ireland and the United Kingdom - may at any time request to take part in some or all of the Schengen acquis.The Council of Ministers decide on this request on the basis of unanimity of the Schengen member states and the requesting state. The significance of this provision is that Ireland can only participate if the other member states agree to it unanimously.

Where Ireland has opted in to part of the Schengen acquisand a new proposal in that field is introduced, Ireland can give notice to the Council of Ministers that it will opt out but can withdraw that notice at any time up to the adoption of the measure. This opt-out is tempered by a set of procedures in Article 5 described as "fiendish" by Stephen Peers, a leading authority in the field. The purpose of the procedures is to protect the coherence of the Schengen acquis. The risk for Ireland is that the underlying Schengen acquiscould be dis-applied to it and Ireland would have to bear any direct financial consequences of this should the decision be that Ireland's opt-out from the amending measure would cause too much incoherence for the system. Should Ireland chose to opt from an amending measure, having opted into it, the stakes are very high.

Protocol 20 recognises the special travel arrangements in place between Ireland and the United Kingdom. It first recognises that the UK can continue to exercise border controls and then that the United Kingdom and Ireland can have special arrangements for the movement of people between them. As long as this common travel area exists, then according to the protocol Ireland can also have border controls.

There are two consequences to note from this. First, as Protocol 20 states, the other member states can impose border checks on people coming from Ireland and the United Kingdom. Members no doubt have experienced this when they travelled to the Schengen area. Second, the exemption for Ireland to impose border controls only applies as long as the UK and Ireland maintain their common travel area. This is important should the UK exit the EU.

Protocol 21, a protocol on freedom, security and justice, provides an opt-in for the UK and Ireland in regard to measures adopted under an EU court's rulings on Title V Part III of the Treaty on the Functioning of the European Union, that is the measures adopted in regard to the creation of the area of freedom, security and justice, AFSJ, dealing with border checks, asylum, immigration, judicial co-operation in civil and criminal matters and police co-operation. This is different from the Schengen Protocol, as the UK and Ireland have a right to opt-in.

Ireland notifies the President of the Council of Ministers in writing within three months of a proposal going to Council that it wants to take part. Its participation cannot be vetoed. Even if Ireland does not participate in the measure, it can subsequently opt-in with the Commission outlining to the Council what arrangements are necessary for Ireland to comply with the measure. Note, a measure can be adopted after a reasonable time without Ireland or the UK, even if they have notified of their wish to opt in, if in practical terms it is not possible to adopt the measure with them taking part.

Where the UK or Ireland opt-out of a measure, then the Council holds a full discussion of the possible effects of such non-participation. Any member state can ask the Commission to examine the situation on the basis of Article 116 of the Treaty on the Functioning of the European Union. Under this provision if the Commission thinks a member state's laws, administrative practices or procedures are distorting competition in the internal market and that distortion needs to be eliminated then the Commission consults the member state. If the consultation does not work, then directives or any other appropriate measures can be adopted under the ordinary legislative procedure.

What this means is that an opt-out decision, in what I believe would be fairly exceptional circumstances, may lead to legislation being adopted if the decision is deemed to distort competition in the internal market. The reason for this opt-out for Ireland seems to have been driven by concerns about the integrity of the common law system and differences with the civil law traditions dominant in other member states and by the fact the UK was going to opt out.

In declaration 56, Ireland affirms its commitment to the AFSJ and indicates it will participate to the maximum extent. Ireland can, at any time, notify the Council in writing that it no longer wishes to be covered by this protocol, and if it does so then the normal treaty provisions apply. This protocol is not applicable to Ireland in regard to Article 75 on the Treaty on the Functioning of the European Union, which sets down rules on freezing funds and financial assets in order to combat and prevent terrorism.

What is the relationship between these protocols? The question of whether a measure is part of Schengen or the AFSJ is significant because, if the Schengen agreement applies, Ireland does not have a right to opt in, which it does have in regard to the AFSJ. There is a substantive overlap, however, between the Schengen acquisand Title V, Part III, and this has been litigated before the European Court of Justice, by the UK in particular. An example is case C-137/05 on Frontex.

If a measure is covered by the Schengen acquis, then it is governed by the Schengen protocol. What has happened is that the court has interpreted this relatively broadly to include complementary measures, that is, any measure that “builds on” the acquis. The term “builds on” is one that would give a lawyer nightmares because it is very fuzzy. It means the precise nature of the relationship between the two protocols is not entirely clear.

Let us consider the UK opt-out protocol in passing. Under Protocol 36, governing transitional provisions, the UK had the choice to opt out of pre-Treaty of Lisbon measures on police and judicial co-operation within five years. As members are probably well aware, it did so and now has opted back in to a large number of measures, the most important of which for Ireland is the European arrest warrant. Ireland did not have this opt-out in the treaty.

The next topic is Ireland and the protocols. Laffan and O'Mahony suggest that Ireland and the UK have opted into measures on civil co-operation, asylum and irregular migration but to a limited extent on visas, border controls and legal migration. They participate in almost all criminal and policing provisions of Schengen and in respect of irregular migration. I have three thoughts on this. First, as the common travel area is significant for relations between the UK and Ireland, it might be worth considering what Mr. Justice Hogan had to say about it in Pacherov. the Minister for Justice and Equality in 2011. At one point, he referred to the “legal archaeology” required to get to the bottom of the common travel area:

While in theory both Irish and British citizens are entitled to arrive here free from immigration control by virtue of the common travel area, increasingly in practice such passengers who arrive by air from the UK are required to produce their passports (or, at least, some other form of acceptable identity document) in order to prove to immigration officers that they are either Irish or British citizens who can avail of the common travel area. Whatever about anyone else, Joseph Heller [who, as members know, wrote Catch-22] certainly would have approved.

This suggests greater clarity on the common travel area would be desirable.

Second, if the UK exits the EU, regard has to be given to a three-way dynamic: the relationship between Ireland and the EU, the relationship between Ireland and the UK, and the relationship between the UK and the EU. It might be useful in this regard to consider the analogy, albeit imperfect, of the Nordic Passport Union and the Nordic Police Cooperation Agreement, whereby free movement is ensured for Norway and Iceland with the other Nordic countries although they are not in the EU. However, they are in Schengen, which the UK is unlikely to join in an EU exit scenario.

Third, these two comments suggest a mini-Schengen may be the best way forward for the UK and Ireland should the UK leave the EU.