The Institution of Mixity: How the EU and Member States Navigate Shared Competences in International Agreements

When it comes to negotiating international agreements, the European Union has developed unique mechanisms to balance the powers of its institutions with the sovereignty of its member states. One of the most important mechanisms in this balancing act is known as the “institution of mixity”. This approach allows both the EU and its member states to be parties to an international agreement, ensuring that areas of shared competence are effectively managed while protecting national interests. In this article, we’ll explore what the institution of mixity is, why it exists, and how it shapes the EU’s relationship with the wider world.

What is the Institution of Mixity?

The institution of mixity is a legal and political technique that allows the EU and its member states to be separate signatories to international agreements. Unlike treaties signed solely by the EU, where the EU alone holds competence, mixed agreements address areas of shared competence—policy domains where both the EU and individual member states have authority. This means that in areas where the EU cannot act exclusively, each member state must also sign and ratify the agreement alongside the EU. Mixity is therefore essential for agreements that fall partially under EU jurisdiction and partially under the jurisdiction of member states. Some common examples include trade agreements that encompass a broad scope, such as investment, environmental protections, or labor standards, which may extend beyond the EU’s exclusive competence.

Why is Mixity Necessary?

The need for mixity arises from the EU’s division of competences with its member states. According to the Treaty on the Functioning of the European Union (TFEU), certain policy areas are under exclusive EU competence, meaning only the EU has the right to make binding decisions or agreements. Examples include the customs union, competition rules for the internal market, and common commercial policy. However, many areas fall under shared competence, where both the EU and member states have authority to act. In these cases, the institution of mixity allows the EU and its member states to cooperate on international agreements that require both levels of governance. Without mixity, it would be difficult to negotiate comprehensive agreements that touch on multiple policy areas, as member states would be excluded from the negotiation and ratification process. The need for mixity is also evident in the Comprehensive Economic and Trade Agreement (CETA) with Canada, which encompasses a wide range of issues, including investment protections and environmental standards, areas where both the EU and member states have shared competence. By allowing both the EU and its member states to be parties to CETA, mixity ensures that national interests and EU-wide policies are both represented.

How Mixity Works?

In negotiating a mixed agreement, the EU, often led by the European Commission, takes charge of negotiations on behalf of both the EU and its member states, while also ensuring that the agreement reflects the interests of individual countries. Once an agreement is reached, it must go through a dual process of signing and ratification, requiring approval from both the EU and each member state. This phase can be complex and lengthy, as national governments, and in some cases, regional parliaments, must individually ratify the agreement. Following ratification, the agreement comes into force, but implementing it requires careful coordination to prevent overlaps or conflicts between EU law and the laws of each member state.

Internal and External Implications of Mixity

The institution of mixity introduces both internal and external implications for the European Union’s governance and international relations.

Internally, it raises questions about the jurisdiction of the Court of Justice of the European Union (CJEU) because mixed agreements involve both the EU and its member states as parties. When disputes arise regarding compliance, the CJEU is often tasked with determining whether an issue falls under EU or national jurisdiction, ensuring that EU law is upheld consistently across member states.

A key example of the CJEU's role in clarifying such issues is seen in Opinion 2/15 (2017), where the court assessed whether the EU had exclusive competence to conclude the EU-Singapore Free Trade Agreement (EUSFTA) on its own, or whether member states’ participation was required. The CJEU ruled that certain provisions—such as those regarding non-direct foreign investment and dispute resolution—were under shared competence, thus making the agreement a mixed one that required ratification by both the EU and individual member states.

Externally, mixity can complicate relationships with non-EU countries, particularly regarding responsibility and enforcement. Because both the EU and individual member states are parties to the same agreement, it may be unclear to outside partners who is responsible for specific commitments. This ambiguity can complicate dispute resolution and enforcement, as non-EU countries may face challenges in identifying whether to address concerns with the EU as a whole or with individual member states.

Consequently, while mixity enables the EU to pursue comprehensive agreements that cover both EU and national competencies, it also necessitates careful coordination and clarity to address the legal and political complexities it introduces.

The Disconnection Clause: A Technical Solution

To navigate some of the challenges that arise with mixity, the EU has developed what’s known as the disconnection clause. Some international agreements contain this clause, allowing EU member states to apply EU law in their relations with each other, while applying the terms of the international agreement to interactions with other treaty partners. In practice, this means that within the EU, member states follow EU rules even if the international agreement might suggest otherwise. For example, under the 2007 Council of Europe Convention on the Prevention of Terrorism, EU countries apply EU counter-terrorism laws in their internal relations, even if the Convention suggests different measures. However, when dealing with non-EU members, they follow the terms of the Convention. This approach prevents conflicts between EU law and broader international agreements and ensures that EU member states remain aligned with internal EU policies.

Conclusion

In conclusion, mixity offers the EU a way to engage in international agreements while balancing the EU’s authority and member states’ sovereignty. Although it brings challenges, such as complex negotiations and potential legal issues, it remains crucial for maintaining unity and effective global engagement. Through mixity, the EU demonstrates its commitment to cooperation and compromise, ensuring that both collective European interests and national concerns are addressed in an increasingly interconnected world.

Addendum: The connection between “Mixity” and “Implied External Competence” in the light of ERTA ruling.

The ERTA case, formally known as Commission v. Council (C-22/70), is a landmark ruling by the European Court of Justice that laid the groundwork for the EU’s future role as an international actor by clarifying the EU's competence in external relations. This case established the principle of implied external competence, meaning that the European Community could assume authority over certain external matters if they were connected to its internal powers. Specifically, the Court ruled that the European Community had the authority to negotiate international agreements if those agreements were linked to areas of competence that the Community already governed internally.

Following ERTA, it became clear that many international agreements would require the participation of both the EU and its Member States in a mixed capacity, the abovementioned structure of "institute of mixity." This case clarified that the EU, by virtue of its internal powers, could also have exclusive or shared external powers.

In essence, the principles of implied external competence and mixity are interconnected: implied external competence allows the EU to act internationally in alignment with its internal powers, while mixity ensures joint EU-Member State involvement in agreements where competences overlap (shared competence).