European Union Court of Justice Series: Interview with Judge Eugene Regan

Episode #14 December 18, 2025
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Borderlines CJUE podcast cover image episode 14

Berkeley Law’s Borderlines podcast host, Professor Katerina Linos, and guest co-host, Professor Mark Pollack (Temple University), conduct a special interview series profiling Judges and Advocates General serving at the Court of Justice of the European Union (CJEU) in Luxembourg.

Episode #14 of the Borderlines CJEU Series features CJEU Judge Eugene Regan in conversation with Professor Katerina Linos. Appointed as a Judge at the Court of Justice in October 2015, Judge Regan was elected President of Chamber by his peers and served in that capacity between 2018 and 2024. Judge Regan recounts his early background in Ireland working in agricultural policy, the original common policy and dominant economic activity of the then-European Communities. His distinguished career as a Barrister in Dubin and political leadership as a member of the Irish Senate fostered unique legal perspectives brought to bear during his long experience as Judge at the Court.

In the interview, Judge Regan shares insights into the impacts of the United Kingdom’s 2020 withdrawal from the EU (“Brexit”) on Europe and the Court. He also educates on differences between common and civil law approaches to jurisprudence. Listeners will learn in-depth about the CJEU process for drafting single collective rulings with no dissent among 27 Member State Judges, the influential yet non-binding relationship to independent signed opinions by Advocates General, and the prominent role of Judge Rapporteurs. Judge Regan clarifies the paths for cases to reach to the Court, via infringement proceedings, direct actions, or, most often,  references from national courts. Throughout, he emphasizes the Court’s primary function as interpreter of EU Law, and explains responsibilities of the European Commission and Council.

Cases discussed cover issues of national and international resonance, including border controls, rule of law enforcement, balancing privacy rights and public security, and the role of courts in examining and regulating governmental legislation. Judge Regan brings listeners up-to-date on challenges facing Europe’s highest court, from historic changes brought by EU Treaties, to a shift in emphasis from economic issues like the common market toward fundamental rights and first principles, to ensuring and protecting judicial independence.

Born in Kilcoon, Ireland, Judge Regan studied at University College Dublin to earn his undergraduate degree, and a master’s degree in political economy. He earned a second master’s degree in international law and comparative law from the Free University of Brussels, Belgium. During his career, Judge Regan spent a year as an economist at the Irish Farmers Association (IFA) and from 1975 to 1979, he worked for the protection of Irish agricultural sectors as Director of the Office of the IFA at the European Economic Community. He served as Chief Executive of the Irish Meat Exporters Association (Ireland) from 1980 to 1984. After serving as policy adviser to Peter Sutherland, the Commissioner for Competition in the European Commission, between 1985 and 1988, he returned to work in the Irish meat trade market from 1989 to 1995.

Judge Regan has been a Barrister at the Honorable Society of King’s Inns (Dublin) since 1985, practicing at the Bar of Ireland from 1995 to 2005 and as a Senior Counsel there from 2005 until his judicial appointment in Luxembourg. From 2007 to 2011, he was also a member of the Seanad (Ireland’s Senate). Judge Regan also served as Director of the Irish Centre for European Law in Dublin.


Cases and sources mentioned in the podcast:

  • Link to 1962 Common Agricultural Policy at a glance

https://agriculture.ec.europa.eu/common-agricultural-policy/cap-overview/cap-glance_en

https://www.ireland.ie/en/eu/

https://guides.loc.gov/brexit

  • Links to UK-EU Relations blog posts on CJEU cases concerning Brexit by theme

https://eurelationslaw.com/blog/cjeu-cases-about-the-withdrawal-agreement-part-1-on-citizenship-rights

https://eurelationslaw.com/blog/cjeu-cases-about-the-withdrawal-agreement-part-2-on-intellectual-property-cases
https://eurelationslaw.com/blog/cjeu-cases-about-the-withdrawal-agreement-part-3-on-judicial-cooperation

  • Links to C‑516/22, Commission v United Kingdom (Judgment of the Supreme

Court) case judgment press release and Advocate General Emiliou’s opinion (infringement proceedings against the United Kingdom for possible breaches of EU law committed before the end of the Brexit withdrawal transition period in Micula et al. v. Romania case)
https://curia.europa.eu/jcms/upload/docs/application/pdf/2024-03/cp240047en.pdf

https://curia.europa.eu/juris/document/document.jsf?text=&docid=279505&pageIndex=0&doclang=EN&mode=req&dir=&occ=first&part=1&cid=9519892

  • Link to Northern Ireland Protocol and Windsor Agreement research guide

https://commonslibrary.parliament.uk/research-briefings/cbp-9548/

  • Links to the Bar of Ireland (Law Library) and Law Society of Ireland

https://www.lawlibrary.ie/
https://www.lawsociety.ie/

  • Link to history of the Delors Commission (EU internal market)

https://ec-europa-eu.libguides.com/ec-history/delors/ec-composition

  • Links to joined cases C-368/20, NW v. Landespolizeidirektion Steiermark and C-369/20, Bezirkshauptmannschaft Leibnitz judgment press release and Advocate General Saugmandsgaard Øe’s opinion (maximum duration of internal border control)

https://curia.europa.eu/jcms/upload/docs/application/pdf/2022-04/cp220064en.pdf
https://curia.europa.eu/juris/document/document.jsf?text=&docid=247108&pageIndex=0&doclang=en&mode=lst&dir=&occ=first&part=1&cid=9524934

  • Link to Schengen Borders Code regulation

https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:32016R0399

https://curia.europa.eu/jcms/upload/docs/application/pdf/2023-06/cp230089en.pdf
https://curia.europa.eu/juris/document/document.jsf?text=&docid=268622&pageIndex=0&doclang=EN&mode=req&dir=&occ=first&part=1&cid=9531621

https://curia.europa.eu/jcms/upload/docs/application/pdf/2024-03/cp240050en.pdf
https://curia.europa.eu/juris/document/document.jsf?text=&docid=275040&pageIndex=0&doclang=EN&mode=req&dir=&occ=first&part=1&cid=9537201

  • Link to Article 77.3 of the Treaty on the Functioning of the European Union (TFEU)
    (identity cards)
    https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:12008E077
  • Link to Article 20.2 of the Treaty on the Functioning of the European Union (TFEU) (free movement)
  • Link to C-120/78, Rewe-Zentral AG v Bundesmonopolverwaltung für Branntwein case judgment (“Cassis de Dijon,” EU principle of mutual recognition for goods)
    https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:61978CJ0120
  • Links to C-64/16, Associação Sindical dos Juízes Portugueses v. Tribunal de Contas case judgment press release and Advocate General Saugmandsgaard Øe’s opinion (Portuguese judges’ salary reductions and judicial independence)

https://curia.europa.eu/jcms/upload/docs/application/pdf/2018-02/cp180020en.pdf
https://curia.europa.eu/juris/document/document.jsf?text=&docid=190793&pageIndex=0&doclang=EN&mode=req&dir=&occ=first&part=1&cid=9547212

  • Link to Article 2 of the Treaty on European Union (TEU) on core EU values

https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:12012M002

            https://curia.europa.eu/jcms/upload/docs/application/pdf/2018-10/cp180144en.pdf
            https://curia.europa.eu/juris/document/document.jsf?text=&docid=204424&pageIndex=0            &doclang=EN&mode=req&dir=&occ=first&part=1&cid=9553377

  • Links to C-284/16, Slowakische Republik v. Achmea BV case judgment press release and Advocate General Wathelet’s opinion (reference for a preliminary ruling; bilateral investment treaty, arbitration clause not compatible with EU law)

https://curia.europa.eu/jcms/upload/docs/application/pdf/2018-03/cp180026en.pdf
https://curia.europa.eu/juris/document/document.jsf?text=&docid=194583&pageIndex=0&doclang=EN&mode=lst&dir=&occ=first&part=1&cid=9557733


Selected speeches and publication for further research:

Citation:  Linos, Katerina and Pollack, Mark. Episode #14: Interview with Judge Eugene Regan. Borderlines podcast, European Union Court of Justice Series (December 18, 2025).

https://www.law.berkeley.edu/podcast-episode/european-union-court-of-justice-series-interview-with-judge-eugene-regan/

Berkeley Law’s Borderlines features exclusive content with the world’s leading international law experts. Check out recent interviews with former ICJ President Donoghue and ICC President Hofmanski – be sure to subscribe so you don’t miss an episode! And please rate Borderlines on Apple Podcasts, Spotify, or your favorite app, which can help others find useful resources. Thanks for listening!


Episode Transcript

Judge Eugene Regan Interview

Katerina Linos: Welcome to Borderlines. I’m Katerina Linos, the Michael Heyman Professor of Law at the University of California at Berkeley.

Mark Pollack: And I’m Mark Pollack, Freaney Professor of Political Science and Law and Jean Monnet Chair at Temple University.

Katerina Linos: This is our series of interviews conducted in summer and winter 2024 with the Judges and Advocates General of the Court of Justice of the European Union in Luxembourg.

Little is known about the backgrounds, careers, and personalities of the key decision makers on Europe’s highest court, and we hope to create an archive to shed light on these jurists.

In today’s episode, we speak with Judge Eugene Regan of the Court of Justice of the European Union. Judge Regan brings a remarkable perspective to the Court, combining his background in agricultural policy – working at the heart of Europe’s original common policy – with distinguished careers as a Senior Counsel in Dublin and member of the Irish Senate.

Our conversation traces Judge Regan’s unique path from economist at the Irish Farmers Association to Director of their Brussels office during the formative years of the European Economic Community. His experiences bridging Ireland’s agricultural interests with European policy fostered the distinctive legal perspectives he brought when appointed to the Court in 2015, where he was elected President of Chamber by his peers and served in that capacity from 2018 to 2024.

We explore how Brexit has reshaped both Europe and the Court’s work, delving into complex cases involving the UK’s withdrawal. Judge Regan illuminates the fascinating differences between common law and civil law approaches, and explains the CJEU’s distinctive process for crafting unanimous rulings among judges from 27 Member States – with no dissenting opinions published.

You’ll learn about the Court’s three pathways for cases: infringement proceedings, direct actions, and references from national courts. You’ll learn about the influential role of Advocates General, whose independent signed opinions guide but don’t bind the Court. We discuss cases ranging from border controls and asylum policy to judicial independence and the balance between privacy rights and public security. As Judge Regan explains, the Court’s focus has evolved from economic issues like the common market toward fundamental rights and principles, even as it faces challenges in protecting judicial independence across Europe.

Katerina Linos: Judge Regan, I am absolutely delighted to be talking to you today. You’ve had a unique career trajectory. In fact, you started in agricultural policy, an area which is associated with a different class from the class of people who make laws, from the class of people who are well-represented among the Judges here, even though it’s an area of financial significance for the European Union that is tremendous. You then moved on to lead Ireland, and have been a Judge on the Court for a very long time.

I want to start with your early years. That too is of great interest.

Judge Eugene Regan: I can start by saying that, when we talk about agriculture in the European Union, if we go back to my first involvement, which was when Ireland entered the Union in 1973, the agricultural policy was the dominant policy. It was actually the original, single policy of the Union, and it absorbed a significant amount of the Union budget.

Katerina Linos: Would you say more than 50 percent of the Union budget?

Judge Eugene Regan: Yes, it was, at the time. And the other thing then is, being the only common policy, a lot of European law and legal principles were developed in the context of the common agricultural policy. Very seminal cases of this Court were developed at that time.

So I think that agriculture, also for Ireland, was the dominant economic activity, both basic agricultural production, but also processing. It accounted for the majority of our exports at that time. My involvement in agriculture, both as a lobbyist and as a trader in agricultural products, was an education in many ways, both in a business sense, but also in terms of the institutions and in terms of the economic life at the time, which Ireland has outgrown. It’s still a very significant industry, but of course, Ireland succeeded in attracting foreign investment, with the effect that it has absolutely transformed the economy. Foreign investment – in the context of a European single market; the focus of, and the attraction for, foreign investors.

Katerina Linos: I’ll fast forward to the 2000s, when you served as a member of the Irish Senate. You’ve been a political figure nationally. How does that translate? What were some key takeaways from that era?

Judge Eugene Regan: I was a member of the Irish Senate for the main opposition party, a party that’s now in government. I was a spokesperson on Justice, and Home Affairs. So, it gave me a rather unique insight into both political life, but also into another perspective on the law and how the law is enforced and how the law is constructed.

Being involved in forming legislation gives you an insight into the effort that goes in to formulating legislation and probably you learn that rushed legislation is not a good thing. And that it’s so important that the legislation is well-considered and constructed.

As a judge, it does give you some insight into how to interpret the intention of the legislature, and what is the actual objective of the legislation. But I think being a senator also gives you an appreciation of those basic elements of our democracy: separation of powers, the importance of the independence of the judiciary.

Katerina Linos: I’ll fast forward to Brexit, by which point you were already a Judge on the Court of Justice. You’ve spoken about Brexit, shortly after the referendum. Brexit has now been to some extent completed. Could you discuss some big-picture issues, especially as they impact Ireland? Some issues that an American audience may not have picked up on.

Judge Eugene Regan: Last year we celebrated the 50th anniversary of the membership of the European Union of Ireland and Denmark. It was a joint celebration. In fact, Ireland, Denmark, and Britain joined the European Union at the same time, in 1973, and Ireland and Denmark would not have become Members of the Union at that time had Britain not joined. So, it’s rather ironic 50 years later that we’re celebrating without Britain. Brexit is unfortunate, to say the least. The Union is based on mutual trust between Member States, and Brexit was based on mistrust. It’s a most unfortunate development.

But in terms of the work of this Court, it is business as usual. I think the transition has been rather seamless. We have one less Judge. We have the same number of Advocates General, 11. I think the contribution of the United Kingdom to European law was significant, and indeed, the work of this Court. The notion of precedent, which is now part of our jurisprudence and how we formulate our judgments, is very much based on the common law tradition of precedent.

That really was something which was the input from the United Kingdom and Ireland, but the common law tradition is still present in the Court. As an Irish Judge coming from a common law tradition, it’s also represented to a certain extent by the Maltese and Cyprus Judges. There are certain elements of the common law, which is part of their system of law.

Katerina Linos: I’ve always been fascinated by the fact that this Court, to me, looks a lot like a common law court. In the sense that words, in judgments, say, “We’ll do a teleological interpretation,” which a civil law judge might shy away from. What are some of the common law elements that you see in the jurisprudence of this Court?

Judge Eugene Regan: I’ve never found any fundamental problems in how the common law judge would approach an issue, or indeed, judges from other jurisdictions. When you’re interpreting legislation in Ireland and in the common law systems, you look at the intention of the legislator. Here, we look at the wording of the legislation, the context, and the objective, which is more or less the same. I think that there is a merging of these approaches, of the common law and the civil law systems, which, I think, don’t manifest any great divergences which lead to any problem of interpretation. And I’m in a Chamber in different formations with other Judges from all different jurisdictions and I never find that there’s disputes or difference of views which might pertain to the different systems. It’s more on the subject matter and how one approaches a particular problem at a given time.

Katerina Linos: Can I come back to Brexit? Some of your colleagues said, “Look, we lost Britain and that meant that the quality of argumentation before the Court declined, because agents of Member States are of varying quality, but the British barristers, they were superb.” You mentioned earlier that a State that would consistently intervene was Britain.

I can imagine that this is a loss. I can imagine it is also a gain; that it is easier, to the extent Britain was an outlier, to reach agreement politically, to reach agreement on legal grounds. Could you talk about what happens after Brexit?

Judge Eugene Regan: In my experience as a Member, Britain took the legislation very seriously, was very proper in implementing EU legislation, took the work of this Court seriously in that it intervened in many cases in which it wasn’t the primary party. I think that input is something which is unfortunate that it’s no longer present. We have had judgments this year on issues that arose in relation to the United Kingdom. And yes, there’s no, question about it; the input from the British barristers at our hearings was much appreciated. It is unfortunate, as is Brexit, in general, unfortunate.

Katerina Linos: Some of the questions that were of great practical significance – for example, the loss of EU citizenship of British nationals – seemed like they were legally easy. They seemed to have been determined by three-Judge panels. Is that fair to say, that the legal issues after Brexit, your Court handled pretty straightforwardly?

Judge Eugene Regan: Yes. There were a few cases which went to Grand Chamber, but in general, the implementation of the withdrawal agreements – apart from Northern Ireland; certain problems there – but in terms of the Court work, the issues that came to us were rather easily resolved. We did have a Grand Chamber case – I was Juge Rapporteur in it – which concerned that during the transition period, the U.K. Supreme Court took a decision without waiting for the process to be completed here in terms of issues that had arisen concerning a matter of state aid and arbitration. We did find that the U.K. was at fault in this regard. But again, that’s perhaps one of the last cases that would come before us concerning Britain.

Katerina Linos: And can I just ask, could you explain the basics of Brexit? How can goods travel the island from Northern Ireland to Ireland freely without a border on the island when there now is an external border of the Union?

Judge Eugene Regan: There is a specific Northern Ireland protocol which regulates this, and there is this “Windsor Agreement,” which was finessing that arrangement. And, essentially, there are controls. But, attempt has been made that those controls would be not at borders, based on technology and certain procedures – which would ensure that goods that entered Northern Ireland would be clear that they were destined for Northern Ireland and not for the Republic of Ireland.

I think it’s complex because Northern Ireland has been given a rather privileged position in the withdrawal agreement. In other words, Northern Ireland remains part of the U.K. market and at the same time remains part of the European single market. So, it has the benefit of both worlds. And that does create some control issues, and those issues were very politically sensitive. But I think that all parties did work to ensure that there was no new border created between Northern Ireland and the Republic of Ireland, given the history of that situation.

Katerina Linos: Have there been specific and sharp economic consequences of Brexit for specific industries? And by that, I mean sometimes there are headlines that the florists have a particularly difficult job with border checks, because fresh flowers die very quickly, so a small delay matters. There were big questions about the financial industry and whether London would be – could remain – as a central hub. I have friends of mine who are solicitors and for the first time they said, “Maybe we need to also make use of our dual citizenship with Ireland, also try to pass the examinations in Ireland, because the legal profession might need to shift.”

Have there been some very clear consequences that are visible already?

Judge Eugene Regan: Just on the legal profession side: there are considerable number of U.K. barristers and solicitors who have registered in Ireland, with the different Bar Council and Solicitor Society, so as to ensure their ability to operate seamlessly within the European Union.

In terms of economic effects, I think it works both ways. Certain industries that are time-sensitive have been severely affected. I think in certain cases, many small companies, in particular, have just ceased to operate cross-border. So, it shows that the whole idea is unfortunate and economically, not very sensible, between enormous trading partners in such proximity, to establish controls at borders and barriers to trade. It’s, in fact, totally contrary to the original ideas of Lord Cockfield and Margaret Thatcher at the time. Because the completion of the internal market – which was put forward by the Delors Commission back in the late ‘80s – the completion of the internal market by 1992 was a priority for the U.K. government at the time; to create the single market so that industry could thrive in a broader Union and a broader single market. It’s a regression from that approach.

Katerina Linos: It does seem that, perhaps, people were overly optimistic about the ability of the U.K. to conclude new trade agreements.

Judge Eugene Regan: I don’t wish to get into the sort of difficulties that have been created, but I think the economic evidence is there, that this was not a good thing for the British economy.

Katerina Linos: There seems to be widespread consensus of some regret around that.

Let me turn to the Court. So, the Court is quite different from other domestic and international courts, from many common law courts, in that there’s a single opinion. You were explaining earlier how much editing and drafting and deliberation is necessary in order to come to a single opinion.

Could you talk about how you’ve experienced this? How you experienced the fact that there was a Court opinion – perhaps you’ve been on the minority in many cases or in some cases, but have had to work with your colleagues to have no separate opinions, no dissents?

Judge Eugene Regan: If we put it in the context: if one is a Judge Rapporteur – that’s the Judge who has been given custody of the case, in terms of leading on the case and having the first cut at a case – that Judge would prepare a report for the college of Members, and would propose, depending: present the legal context; the issues that arise in the case and how important those issues are in terms of legal novelty; whether it merits a Chamber of three, a Chamber of five, or a Grand Chamber if the case is very novel, sensitive, and of significant importance that may involve invalidating some regulation or directive. So, that’s the function of the Judge [Rapporteur].

Katerina Linos: Can I interrupt?

Judge Eugene Regan: Yes, of course.

Katerina Linos: It’s amazing how early on the Judge Rapporteur is assigned. Is that determination – this Judge Rapporteur proposes that this is a Grand Chamber case versus a three-Judge case – is that a straightforward determination? Is there a lot of contention over that issue?

Judge Eugene Regan: Once you propose as to a particular formation, any other Judge, or indeed Advocate General, can comment and suggest, “Well, I think this is a more important case and a Chamber of five is not adequate. We should go to Grand Chamber.” We have considerable debate on these type of issues.

It is an issue that is put before the college at our weekly meetings and a determination is made, “Okay. That’s the right call.”

Katerina Linos: Maybe let me move one step before that. So, the President decides to assign the case to a specific Judge. That determination seems to be made, in part, on the basis of continuity, like, if there’s been a similar case, that goes to the same Judge Rapporteur; in part, on the basis of a nationality criterion; so if the case concerns Ireland, you’re unlikely to be the reporting judge. How does that determination go?

Judge Eugene Regan: There wouldn’t be anything about nationality; I suppose that you wouldn’t be given a case concerning your own. But, I think the President would just decide on, a reasonable share out of important cases, and not leave one Judge with, say, cases that are rather straightforward. I think it’s a question of sharing out the cases, and also looking at perhaps a special ability of a Judge in a particular area; it might be intellectual property, it might be competition policy, whatever. It does tend to circulate. It’s not that one Judge would always have competition cases and no other Judge would be involved. So, it tends to move about, the responsibility for particular areas.

Perhaps the President is in the best place to explain exactly on what basis, but I think he attempts to do this in a fair, reasonable way, so that everybody has interesting cases and a variety of cases. And that no Chamber is specifically designated to follow a particular policy area.

Katerina Linos: So, your first step as Judge Rapporteur is to look at the materials and decide, “This is a novel and complicated issue,” versus, “Is it straightforward?” And then there’s some discussion?

Judge Eugene Regan: That’s correct.

Katerina Linos: And it’s assigned to an Advocate General?

Judge Eugene Regan: Then, let’s say the Judge is followed, and it goes to Grand Chamber. Grand Chamber cases, the important cases, would generally require an opinion of the Advocate General. So, the Advocate General would provide his opinion, then the Judge Rapporteur would do a note explaining that, “I propose to follow the general orientation of the Advocate General,” or not. And if he follows, he would always qualify by saying, depending on the reasoning, on how you come to the same conclusion. There might be a certain variation in that.

If you say you’re going to follow the Advocate General, or not, any other Member in the formation can issue a note to say, “I think we should go a different route.” And then we have what’s called a tour de table. The Judges in that formation would sit around the table, discuss it, and agree on the general orientation on which the judgment would be drafted. Then the Judge and his cabinet would draft a judgment that would go for deliberation. And all of the other Judges at that stage would have a say. And we have a final meeting to adopt a judgment.

Katerina Linos: Can I ask what the norm is when there’s going to be a disagreement between the Advocate General and the Judge Rapporteur? You said in about 20 percent of cases this happens; it’s not infrequent. Would you knock on the door and say, “Hey, here’s a heads-up. I think I’m going in a different direction,” or is there perhaps the opposite norm of confidentiality, that you don’t talk about the disagreement until the end? Or maybe there’s lots of debate back and forth?

Judge Eugene Regan: No, it’s an important question because the Advocate General is acting independently, and you’re not discussing it with him or her as to what his opinion should be.

That’s a completely separate operation and the Advocate General is acting completely independent in giving his opinion. It’s only after that opinion is formally issued that one comments as to whether you intend to follow that opinion or not.

Katerina Linos: And then when there’s disagreement, you said there’s a tour de table. There’s more discussion.

Judge Eugene Regan: That’s right. Then the formation, the Judges involved in that case, would decide essentially, “I think we should go this way.” In other words, it would be, “What is the result? What is the decision?” And how that’s argued is then left to the Judge Rapporteur in drafting the final judgment.

Katerina Linos: So, the Judge Rapporteur will again draft the decision. Perhaps this will be contrary to what the Judge Rapporteur proposed, but he’s also responsible for the –

Judge Eugene Regan: No, no, the Judge Rapporteur drafts the opinion –

Katerina Linos: – of the Court.

Judge Eugene Regan: It could be not precisely what that Judge Rapporteur wanted, in terms of his appreciation of the case.

Katerina Linos: When I read cases, sometimes I see a lot of reference to the Advocate General. The Court says, “And as Advocate General said, in paragraph 70, this is the reasoning.”

And at other times, the name of the Advocate General is at the top of the case and there’s no reference. Is there a norm about citing extensively to the Advocate General when the Advocate General is followed, but not when the –

Judge Eugene Regan: It’s really just the style of the Judge Rapporteur and ultimately of the formation, where the Advocate General – there’s a certain statement in the opinion, which is novel and interesting and it’s embodied in the judgment. One can quote the Advocate General, in certain aspects, even though the judgment is not in line with the Advocate General’s opinion. It’s just that there’s something interesting that has been said by the Advocate General in his opinion that can be usefully embodied in the judgment and to strengthen the reasoning in the judgment.

Katerina Linos: You’ve certainly had your fair share of interesting opinions as Judge Rapporteur. So, I thought I would turn to one of those. I’m fascinated by the case of NW v. Landespolizeidirektion Steiermark. This was a case on temporary border controls within Schengen. This was a very high-profile case. It followed the 2015 migration crisis. Austria put in place border controls and extended them, exceeding many limits. The Advocate General had proposed a flexible approach. The Court took a pretty strict approach and said, “The reintroduction of internal border controls for extended periods, when you’ve got the same threat, is not consistent with the Schengen Agreement.”

So, to me, this is fascinating for procedural reasons. It’s fascinating for substantive reasons. If you want to, talk about any aspect of this case and then I’ll ask about some other aspects.

Judge Eugene Regan: I suppose the Schengen border code or Schengen Agreement provides for free movement internally within the European Union and that there are no checks at the borders, on passports or otherwise, internally within the Union. It’s consistent with that principle of free movement. That Agreement has been in place for a long time. In that Agreement, there is provision for temporary introduction of border controls. That’s where there’s a threat to security, or a perceived threat to security, or perhaps a terrorist threat, or whatever.

The framework that’s provided is that it’s temporary. It’s to deal with a particular emergency, and it’s not designed to be permanent. The wording in the legislation is rather clear and inescapable. When you ask about flexibility: the legislation provides that; reintroduce border controls for 30 days, and you can extend that, but not more than six months.

In addition, there is another provision which allows the Council of Ministers to recommend border controls for six months, which can be extended. That’s for two years. Now, whatever the crisis is, it would seem that it should be possible to resolve within that period. In this case, you had border controls introduced. Then you had four Council recommendations. So that’s two-year border control, and then it was still maintained. The framework provides the principle of free movement, but that’s an exceptional measure, to introduce border controls designed to be temporary, and not permanent.

And in this case, it took on the demeanor of a permanent border control. Just on practical terms, this was at the border with Slovenia and Hungary. I think when people are waiting at the border in their cars for 12 hours or more, unless there’s a very good reason for those border controls, this is found to be, on a practical level, rather unacceptable and not in keeping with the general principles on which the whole Schengen Agreement, and indeed the Union is based on free movement.

There is flexibility. In fact, you see in the Euro 2024 soccer competition, Germany has reintroduced border controls, having a concern about rioting or bad behavior by soccer hooligans, or whatever. This is an example of the type of situation where you might reintroduce border controls. So, the Court was rather bound by the literal wording of the legislation. And, if it’s considered that change is needed, then it’s for the legislature to do that, rather than the Court.

Katerina Linos: Let me ask about the significance of Schengen. I remember when Schengen was first introduced, when the Euro was first introduced. People started talking about variable geometry: “Some Member States will be part of Schengen, some Member States will be part of the Euro, others will not.” This is fine. And you said, and President Lenaerts said, “Schengen is basic to European free movement. This is what we’re about.” Is that the understanding of Schengen? That we shouldn’t have border controls?

I also remember – again, coming from Greece – the borders closing very harshly in the migration crisis. There was headline news for quite some time, that there would be movements of asylum seekers. They would camp out in front of the border. They would not believe the authorities that the border would open. The border would not open. The police would move them internally. How does Schengen work these days?

Judge Eugene Regan: It’s very, very straightforward. It’s about internal borders. And if there’s a crisis, there’s provision there for action to be taken. You control the borders and you take whatever measures are necessary. But the idea is that this would be temporary until that crisis has passed and it shouldn’t become permanent. And if it’s permanent crisis, then some other measures need to be adopted by the legislature.

But from the Court’s point of view, we are a court of interpretation. We interpret the regulations, we interpret the directives and the Treaty. In this case, you have very specific provisions laid down by the legislature, and it’s rather difficult to deviate from them. In certain cases, the Court, of course, has a margin of discretion. But when the literal wording of a directive or regulation provides for, in clear unequivocal terms, that “six months is the maximum” – bearing in mind that there is this other provision which allows a two-year period where control measures can be in place – it would seem to be inescapable, the conclusion that one must come to.

Katerina Linos: This to me seems very straightforward. I think you’re right, that if the case comes to the Court, a textualist interpretation will lead to a politically very significant result. But I did want to ask about how these cases come to the Court.

It seems that the Commission could have brought this case, and didn’t seem to do that. Instead, an activist, a European lawyer, decided to go and try to cross the border and show his driver’s license rather than his passport or identification document. Could you talk about how this and other cases come to the Court so that the Court can enforce these?

Judge Eugene Regan: Interesting question. Because the Court really receives cases in three respects, principally. One is where the Commission takes infringement proceedings against Member States for their failure to comply with EU law. The second is direct actions, where there’s cases – in terms of antitrust competition policy; cases on state aid, illegal state aid – which come before the General Court here first, and then on appeal to us. So, infringements, appeals.

But, the vast majority is interpretation that is requested. That’s questions of interpretation, which are posed to us by national courts from across Europe. This chap who tried to cross the border, he was asked for his passport, refused, and then referred. That case comes before the national court, and then is referred to us. So, we are asked for an interpretation of EU law. We don’t decide the cases. We interpret the provisions which is causing difficulty for the national judge, and then it goes back to the national judge to implement EU law. It’s a dialogue with the national court. That’s how it operates. And that’s how the cases come to us. Those references from national courts – probably 80 percent of our case law.

Katerina Linos: Is it fair to say that, not only the volume of preliminary references has increased, but also the Commission, some academics say, has not been as active in bringing infringement cases as in past years? Is that your experience?

Judge Eugene Regan: Well, we still get a significant, reasonable number of infringement cases. But I would have thought that on the big issues . . . the Commission have acted, but perhaps prioritize the cases that they bring before us.

Katerina Linos: Coming back to a final question on the Landespolizeidirektion Steiermark case: do the rulings give enough flexibility to Member States that might face a big crisis, that might have an influx of undocumented migrants, that might have a soccer tournament, that might have a terrorist attack, that might need to close the border? Are you comfortable with the flexibility that is given and also the deference that’s given to the idea of free borders? Is that the right balance?

Judge Eugene Regan: The balance is set down by the legislation and I don’t think that there has been any particular crisis of security or terrorist threats where Member States have not been able to act within this framework provided by the Schengen Code and the exemption which allows border controls to be reintroduced in the case of necessity. I’m not conscious of any particular event or otherwise, where Member States have said, “This is unworkable.” But, if it is unworkable, then the Member States need to look at it again, and that should be reflected in new legislation.

Katerina Linos: Do you happen to know what happened after you issued your opinion? Whether the lower courts ended up complying with the judgment? Whether the Austrians said, “Okay, it’s about time!”?

Judge Eugene Regan: I think Member States tend to comply with our judgments. And, if our judgments are not complied with, there is a remedy. It can come back to us and there are financial penalties for not implementing our judgments.

Katerina Linos: On the financial penalties, my understanding is that there was a big recent case in which Hungary was told to pay 200 million Euro, plus a million Euro a day. But that that was unusual. That was the largest financial –

Judge Eugene Regan: No, we’ve had situations also in relation to the rule of law issues in Poland, where daily fines have been imposed. I think one of the first times that the daily fines were imposed was actually in a Greek case, many years ago, an environmental case.

Katerina Linos: We didn’t burn our trash properly.

Judge Eugene Regan: I think that brings it home to Member States, that there is a price to be paid for non-compliance, because where one Member State doesn’t comply, that’s unfair to other Member States to comply with EU law.

Katerina Linos: And also, I think sometimes to the citizens. Some Hungarians and Poles say, “You should be doing more.” I remember that Greek case, because it is shocking how beautiful Greece is and how ugly the most beautiful beaches can be made by waste mismanagement.

Judge Eugene Regan: I think on the environmental front, Europe has played a big part.

Katerina Linos: I’d like to turn to a different significant case: RL v. Wiesbaden. This was a case about biometric data in ID cards. Again, you were the reporting judge. To me, what was interesting about this case – to begin with, I’ll start with the substance of it and then I want to talk about the procedure – is that you said, “At the end of the day, there’s nothing wrong with fingerprints on ID cards. There’s no violation of fundamental European rights there.” This Court has a very extensive body of privacy rulings, that are different from what we have in America, that are quite strict.

How do you feel about the boundary between privacy and security for this case? Was it straightforward that this was the right balance?

Judge Eugene Regan: Well, in this case, what was involved was the regulation, which provides that all new identity cards – let me start with passports. Passports – it’s already provided for, that you have fingerprint and visual image. But this was to be introduced for identity cards. Now, the interesting thing about identity cards is that many people use identity cards in Europe like passports. It’s used with their national authorities, and I think there were about 50, 60 or more different types of identity cards. So, when they are presented at a border or in another Member State, the authorities don’t know whether they should give credence to these identity cards.

The whole idea was to have identity cards that interoperable standards are established. You have the two fingerprints, facial image, etcetera. So, you have an individual who objected to providing the two fingerprints, on the basis that that was an invasion of his privacy. There was a complication in the case in that the legal base on which that regulation was adopted was found by the Court to not be the appropriate legal base, in that the base was one based on free movement, and the matter could be decided by a qualified majority. Whereas there was a specific legal basis in the Treaty, which mentions identity cards, passports, and residence permits. The Court tended to, ultimately, consider that that base was the appropriate base, and that requires an unanimity of the decision by the Ministers.

But what the Court did, it did find on the substance the regulation to be valid; that in measuring – the balancing the issue of the objective of this regulation, which was in the public interest, against the extent of the seriousness of the interference with the individual right to privacy – it found, on balance, that it was proportionate.

So, that’s what the case was about. And I think in that case, if one talks about a dichotomy or a balance between security and privacy, I think the legislature and the Court found that that was a reasonable balance.

Katerina Linos: I’ll turn to the legal basis question in just a second, because I’m fascinated. In the U.S., we don’t have identity cards. And there’s huge opposition from the left and from the right, or from certain groups. The left-wing arguments are: because we have undocumented immigrants; because we don’t have identity cards, we have racial profiling; because we don’t have identity cards, we have other kinds of profiling, other kinds of leaks of our social security numbers. There’s some effort to systematize this and it’s unlikely that we will have national identity cards. And even getting the states’ drivers’ licenses to be more uniform and have more security measures, similar to passports, is hugely controversial.

I grew up in Greece. I always carry my identity card. It’s not very secure because it’s an old one. But, there’s no such debate on civil liberties or other grounds.

Judge Eugene Regan: Just on that, if I may – because in Ireland, the view would be as you’ve described it. We don’t have identity cards, as such. Denmark doesn’t have identity cards, as such. And this regulation provided that no Member State has to provide for identity cards, but it provides that if you do, then it should be according to these rules.

Katerina Linos: I will show you my Greek identity card, and you will see the usefulness of the rules. [Laughter] Okay. So it’s lighter. It’s not a requirement of identity cards. It’s just says, “These identity cards should not be very easily falsifiable.”

Judge Eugene Regan: Exactly.

Katerina Linos: Let me turn to the legal basis question. So what you did in this case is, you said, “Legislator, you need unanimity.”

Judge Eugene Regan: Yes. Well, we didn’t put it that way. [Laughter] We said, the appropriate legal base is this Article, as it happens, 77.3, which is more specific in that it has mentioned identity cards and passports, etcetera. Whereas the other, 21.2, provides for free movement, and it was on that basis. One could argue it both ways, but ultimately the Court decided that the more appropriate legal base was 77.3.

Which creates a problem. Because, in fact, on that basis, the regulation is invalid. We did something which we don’t do in many cases, but we did in this case decide that this was rather important regulation, that it would affect people if it was simply invalid and inoperable, and decided that the effects of the regulation should be maintained. And in fact, we gave the Council quite a considerable period to rectify this in terms of the legal base: two years from the 1st of January of the year following our judgment.

Katerina Linos: One possible criticism of the Court is that you do too little invalidation. National constitutional courts examine government decisions and invalidate them every day. But, it is hard to find cases like this, where you invalidate even by saying, “There is no fundamental rights principle; there is a wrong legal basis.” There are not many cases in which the Court of Justice says, “The European Commission, the European Council, exceeded their authority and regulated on a matter that is a Member State competence.” Am I wrong on this?

Judge Eugene Regan: When you talk about “many cases” – there are considerable incidences of where we have invalidated EU legislation on the grounds of disproportion. But this was only invalidated on a technicality; that on the substance, the Court did not consider that there was a justification for invalidity. But the Court doesn’t hesitate, and there are numerous examples of where the Court has invalidated.

Katerina Linos: I clearly need to do more reading. Maybe you could tell me a couple of cases that I really need to follow up on.

Judge Eugene Regan: Off the top of my head, I’m afraid I cannot. But, I’m thinking of cases that are going through the Court at the moment, and the issue of validity is very much an issue. I don’t necessarily rule out that certain aspects, or otherwise, of legislation will be deemed invalid.

Katerina Linos: Thank you so much for that. As we conclude, I wanted to ask you about the evolution of the Court and its jurisprudence. When I was first taught EU law, we were learning things about the common market, about primacy, about issues that are largely settled.

And it seems that the Court, in the last few decades, has been taking on a lot of migration and borders areas; a lot of European identity cases; a lot of cases on the rule of law. The Treaty amendments and the pace at which secondary rules are issued is very fast. How have you seen the Court’s jurisprudence evolve in your lengthy tenure here? What are some challenges for the future?

Judge Eugene Regan: Originally, of course, the Union was concerned with this discussion; with common agricultural policy and its provisions, economic issues, border control – economic border controls. Because when the European Economic Community was created, there were still restrictions at borders. In fact, it was a judgment of this Court which helped in reducing those border controls, in terms of mutual recognition, where a product was lawfully marketed in one Member State, it could be marketed in another. That actually did lay the basis for the completion of the internal market, back 30 years ago.

With the changes of the EU Treaties, of course, the Unionization, or the communalization, of a lot of issues and a lot of policy areas naturally has extended the areas in which the Court gives judgments. And questions that arise from national courts – asylum – they are originally economic issues, but it’s more issues of fundamental rights.

Of course, the most recent was the rule of law, where we seem to have gone back to first principles. That arose, of course, from threats to the independence of judiciary in some Member States, and in particular, that was highlighted in Poland under the previous government. But it came to our attention, curiously, from a case referred from Portugal where it was suggested that the reduction in salaries of Portuguese judges was a threat to their independence. Now, this Court decided that there was no threat in this instance to independence, since judges were not being targeted. It was a general austerity measure which applied to judges as to other functionaries. But in that judgment, we did elaborate on the principles of what constitutes an independent judiciary. There was a lot of jurisprudence developed on foot of that judgment. And indeed, the Commission acted following that judgment in taking infringement proceedings against Poland, in respect of the rule of law, which I think have borne fruit. Mainly, perhaps, due to a change in the economic context.

But, this is the type of cases that come up, which are not in line with the original type of cases that we dealt with. The rule of law issues; of course, we have environmental cases. We have a lot of issues concerning privacy and data protection; a very big issue. I think the rule of law issue will be with us for some time. And I think the role of the Court is – despite the political context might change, and it is changing as we speak – that the Court maintains and upholds the Treaty, the rule of law, the principles of independence of judiciary and the values which all Member States have subscribed to.

Katerina Linos: Can I just add to that? It seems to me that the Court has made certain moves that not every court would make. In the Portuguese judges cases, you could say, “Well, we didn’t have to spell out what an independent judiciary is. We could just say, ‘austerity measures are not a threat.’” In cases involving Article 2 – which someone might say is non-justiciable, others might say is justiciable – the Court has given a lot of weight to these values that are quite broad. I think in the cases involving Hungary and Poland and the Parliament, the Commission has gone first – or has gone somewhere – and then the Court has sometimes gone further than the Commission or the Council. How do you see the role of the Court in what is a very difficult situation?

Let me put this differently. I’ve heard many Judges here speak of a “living constitution,” and that in the U.S. is code for “progressive, activist judges.” We also have our textualist, originalist judges; words like “teleology” would never appear in the judgments of any other international court.

But the threat of Russia is real. The threat of rule of law challenges, in several EU countries, are real. How do you see the role of a court that, at the end of the day, has text to interpret in dealing with these challenges?

Judge Eugene Regan: The Court is a court of interpretation. That case that came from Portugal – the Court was obliged to consider: what is an independent judiciary? What is the basic principles that apply in terms of an independent court? And indeed, there were cases before the Portuguese case; the Wilson case involved an English barrister here in Luxembourg, where the Court already had spelled out, in terms of independence of internal independence – that a court and judges must be impartial, and must be free from external pressures as well. Really, it was an elaboration of those principles, which the Portuguese case gave rise to. When the Polish cases came to our door, these principles are already established and are rather self-evident. It was applied in all of those cases that came from the Polish judges who found themselves under threat from political pressures. It was really, I would say, not revolutionary in any respect. It was really just pointing out the obvious.

Katerina Linos: Thank you so much. The last question I always ask is: what did I not ask about? What should I really have asked about?

Judge Eugene Regan: Well, I think you’ve covered the ground. . .

We were speaking about the infringement proceedings that the Commission took against the United Kingdom. When I said “the Commission” – it’s provided in the Treaties that the Commission is the guardian of the Treaties. So, it has a responsibility to ensure that Member States comply with the regulations, directives, and EU law in general. But, we have this case, a long-running arbitration proceedings, and issues concerning an arbitration award. The Commission disagreed that it was contrary to EU law and EU state aid rules. The United Kingdom Supreme Court took a decision during the transition period. Now the High Court in England, the Court of Appeal in England, had said, “No, we should not take a decision until the European courts have ruled on this,” because, normally, that is the rule, in terms of loyal cooperation between the Commission and the Member States, that they would refrain from taking a decision until the European Court had ruled on the matter.

The Supreme Court took a different view, and ruled on the matter contrary to what this Court had ultimately decided in relation to this issue. We found that the Commission’s views were valid and we found that Britain had failed to fulfill its obligations under the Treaty in various respects.

What’s unusual about the case is that it’s a decision of a Supreme Court that leads to the infringement by that Member State. It’s a rather unusual situation, but I think it was totally correct in this instance. It’s an unfortunate ending to our parting issue that has arisen, given that that’s probably one of the last cases that would concern the United Kingdom, before this Court.

Katerina Linos: Although, there is the German Constitutional Court case in PSPP, which leads to infringement proceedings.

Judge Eugene Regan: Yes. There was a previous French case, as well, but it’s unusual. It’s unusual. Normally, the Courts would refrain from making a decision until the European Court has ruled. Otherwise, you have risk of conflicting judgments, which is not helpful to people. When there’s conflicting judgments, then you have no clarity on the law.

And, you might find interesting the international law aspects. Because the situation is that if a Member State is party to an international treaty – so, it has treaty obligations prior to joining the European Union – then European law does not block that.

In other words, those treaty obligations will prevail. There was a case in Germany, extradition to the United States, where there was an extradition treaty between Germany and the United States and where under EU law, there might have been a difficulty in extraditing the person in question. Because the pre-existing treaty prevailed, a different result followed. It’s a very interesting aspect of the law.

Katerina Linos: The international lawyers all told me to ask about a different case, the Achmea case, to say, “Look, we think this is totally inconsistent with treaty obligations under bilateral investment treaties.” And the European Court did that case; another court says, “No, no, no, intra-EU arbitration is totally consistent with the principles.”

Judge Eugene Regan: Well,  Achmea, the decision – it was an investment treaty between the Netherlands and Slovakia, and there it considered that Member States could not opt out of the EU legal system, so courts were blocked from dealing with issues concerning EU law. It was a very special case. It doesn’t interfere with commercial arbitration, as such. But, it gave rise to a lot of debate. And, this case concerning the United Kingdom also pertains to a similar-type agreement, albeit between Sweden and Romania, if I remember correctly.

Katerina Linos: In the United States, we’re very used to majority opinions and very used to dissents. We’re very used to the fact that the president of the U.S. Supreme Court has a lot of power, because after the votes are counted, he then assigns the majority opinion to a particular Judge. And we know the name of the Judge. We know how broad or narrow, how radical or traditional, the majority and the dissent will be.

And here the Court speaks with a single voice. The reporting judge is assigned very early on. Could you talk more about how you see this comparison between what the Court of Justice of the European Union does and what the U.S. Supreme Court and some other courts do?

Judge Eugene Regan: Throughout the European Union, some Member States – for example, Ireland – does have, its Supreme Court does have dissenting opinions or separate judgments, which might be in agreement with the basic judgment. In other countries – France, I don’t think has dissenting opinions. So, there’s a variation.

In this Court, it’s one single judgment. Because, as I said earlier, we’re a court of interpretation. There’s a dialogue with the national judge. We get references, questions, posed by national courts, asking about an interpretation of EU law. It’s in the context of that dialogue that we make our decisions and give our interpretations. It’s rather important we give a clear, unequivocal answer, which enables the national judge to apply our rulings. To have different interpretations or dissenting opinions, in a Union of 27 Member States – I think it’s perhaps the appropriate system.

You have an Advocate General’s opinion; as we’ve discussed, the Court may deviate from that opinion. That Advocate General’s opinion, in many cases, will outline alternative ways of coming to a decision in a particular case. It perhaps may be seen as a substitute for that dialogue which might give rise from dissenting opinions.

In a community of 27 Member States, there might be pressure on Judges to give a dissenting opinion to reflect sensitivities of their Member States, which would not be a good thing. But, there’s another very important issue. To identify individuals with particular judgments poses a little problem, because the term of the Judges here in the Court is six years, renewable. If one is identified with particular judgments – and our Member State is going to look at how that Judge behaved and dealt with different cases – it does help to ensure the independence of Judges here, that there’s no retribution for particular decisions they might make, and that it’s made as a college.

And, that there’s a single, clear signal as to what is the appropriate result. In this European context, for me, it’s a very appropriate procedure.

Katerina Linos: Although, it does seem that your colleagues in Strasbourg have a different set of procedures – slightly longer terms, non-renewable terms.

Judge Eugene Regan: Yes. Nine years, non-renewable. Again, if it’s nine years, non-renewable, that’s perhaps a better system, in terms of the independence that you can display. And I think Judges do display total independence here. It’s not publicized as to how they vote, how they consider and decide individual cases. And, I think that from the point of view of renewal – those judges who wish to be renewed – I think that perhaps shields them from any type of political pressure of any description, which is desirable.

Katerina Linos: Thank you very much. This has been fascinating.

That wraps up our conversation with Judge Eugene Regan. His insights into the Court’s deliberative process were particularly illuminating – how 27 judges from different legal traditions collaborate to produce single, unanimous rulings without published dissents, and the careful choreography between Judge Rapporteurs and Advocates General.

I found Judge Regan’s explanation of the Court’s evolution especially compelling. From its origins focused on agricultural policy and economic integration to today’s emphasis on fundamental rights, rule of law enforcement, and judicial independence, the CJEU’s role has transformed alongside Europe itself. His firsthand account of navigating Brexit’s legal complexities, from the Northern Ireland Protocol to questions about pre-withdrawal infringement proceedings, reveal how the Court adapts to unprecedented challenges.

The cases we discussed – from border control duration limits to asylum policy disputes, from judicial salary reductions to the delicate balance between national identity cards and free movement – demonstrate the Court’s central role as interpreter of EU law. Judge Regan’s emphasis on the Court’s collaborative relationship with national courts through the preliminary reference procedure shows how European legal integration functions in practice.

If you found this discussion insightful, please rate and share this episode. Our thanks to our producer, Toni Mendicino, our sound engineer, Keith Hernandez, and to the staff of the Court of Justice for making this series possible.