The European Union has developed one of the world’s most sophisticated systems for the protection of fundamental rights. Yet one significant constitutional gap remains: although every EU Member State is bound by the European Convention on Human Rights, the European Union itself is not yet a party to it.
The proposed accession of the EU to the Convention seeks to close that gap. It would make the Union directly accountable under the Convention and subject the acts of its institutions to external review by the European Court of Human Rights in Strasbourg.
After decades of legal and institutional difficulty, the accession process has again reached a decisive stage.
Two European systems of rights protection
The European Convention on Human Rights belongs to the Council of Europe, which is a separate international organisation from the European Union. The Convention is interpreted and enforced by the European Court of Human Rights.
Within the EU legal order, fundamental rights are protected through several sources, including:
- the Charter of Fundamental Rights of the European Union;
- the general principles of EU law;
- the constitutional traditions common to the Member States; and
- the jurisprudence of the Court of Justice of the European Union.
The two systems are closely connected but remain legally distinct. The Court of Justice of the European Union interprets EU law, while the European Court of Human Rights supervises compliance with the Convention.
All 27 EU Member States are parties to the Convention. However, where an alleged violation flows directly from an act of an EU institution rather than from the conduct of an individual Member State, the EU cannot presently be brought before the Strasbourg Court in its own name.
That is the accountability gap which accession is intended to address.
Accession is a Treaty obligation
EU accession to the Convention is not merely a political aspiration. Article 6(2) of the Treaty on European Union provides that the Union “shall accede” to the European Convention on Human Rights.
However, accession is constitutionally complex. The EU is not a State, and its powers are divided between the Union and its Member States. Any accession mechanism must therefore preserve the particular characteristics of EU law while allowing effective external supervision under the Convention.
An initial draft accession agreement was reached in 2013. In its landmark Opinion 2/13, delivered in December 2014, the Court of Justice concluded that the agreement was incompatible with EU law.
The Court raised several concerns, including:
- the autonomy and primacy of EU law;
- the relationship between the Convention and the EU Charter;
- the principle of mutual trust between Member States;
- the allocation of responsibility between the EU and its Member States;
- the proposed co-respondent mechanism;
- the Court of Justice’s opportunity to examine questions of EU law before the Strasbourg Court; and
- judicial review of measures adopted under the EU’s Common Foreign and Security Policy.
The Opinion effectively halted accession for several years.
The revised accession agreement
Negotiations resumed in 2020 through the Council of Europe’s “46+1” Group, comprising the 46 Council of Europe Member States and the European Union. See the Council of Europe’s accession agreement.
In March 2023, the negotiating group reached provisional agreement on a revised package of accession instruments. The revised framework seeks to respond to most of the objections identified by the Court of Justice in Opinion 2/13.
Among its most important features is a co-respondent mechanism. This would allow the EU and one or more Member States to participate together in proceedings where responsibility may arise from a combination of EU law and national implementation.
The agreement also provides for the prior involvement of the Court of Justice where it has not previously had an opportunity to consider the relevant issue of EU law.
These mechanisms are intended to preserve the internal division of powers within the EU while ensuring that applicants are not required to unravel that division before seeking protection.
One particularly difficult matter has remained: the treatment of acts adopted within the Common Foreign and Security Policy. In certain areas, the Court of Justice has only limited jurisdiction. Accession raises the possibility that the Strasbourg Court could review EU conduct which the EU’s own court cannot fully examine.
That tension sits at the heart of the continuing debate over the autonomy of EU law and effective human-rights protection.
Opinion 1/25: the next constitutional test
In November 2025, the European Commission submitted the revised accession agreement to the Court of Justice for an opinion under Article 218(11) of the Treaty on the Functioning of the European Union.
The resulting Opinion procedure 1/25 represents the next major constitutional test for accession.
The Court must determine whether the revised arrangements are compatible with the EU Treaties. A favourable opinion would remove one of the most important legal barriers to accession. An unfavourable opinion could require further amendments, prolonging a process which has already extended across several decades.
Even if the Court approves the agreement, accession will not occur automatically. The final instruments must still pass through the necessary EU and Council of Europe procedures, including approval and ratification requirements.
The process is therefore advancing, but the final destination has not yet been reached.
What would accession change?
Accession would not replace the EU Charter or transfer ultimate authority over EU law to the Strasbourg Court. The Court of Justice would remain the final authority on the interpretation of EU law.
The European Court of Human Rights would instead examine whether conduct attributable to the EU complies with the minimum standards established by the Convention.
In practical terms, accession would:
- bind the EU directly under international law to the Convention;
- make the EU answerable before the European Court of Human Rights;
- allow applicants, after satisfying the applicable admissibility requirements, to challenge conduct attributable to EU institutions;
- clarify responsibility in cases involving both EU measures and national implementation;
- strengthen consistency between the EU and Convention systems; and
- reinforce the credibility of the EU when requiring Member States and third countries to comply with human-rights standards.
This is important because the EU now regulates areas with significant consequences for individual rights. These include migration, border control, sanctions, data protection, competition enforcement, employment, financial regulation, aviation security and maritime surveillance.
Accession would not turn every commercial or regulatory dispute into a human-rights case. However, it would add another layer of accountability where EU action affects privacy, property, due process, non-discrimination or access to an effective remedy.
Why accession matters beyond constitutional theory
The significance of accession extends beyond the relationship between two European courts.
Fundamental rights increasingly influence the design and enforcement of regulation. Businesses operating in regulated sectors already encounter rights-based considerations in administrative investigations, licensing decisions, sanctions, data processing and access to judicial review.
For public authorities, accession would reinforce the need to integrate Convention standards into EU decision-making from the outset. For businesses and individuals, it may eventually provide a clearer route for determining responsibility where a contested measure arises from the interaction between EU law and national action.
At the institutional level, accession would also strengthen the EU’s external position. A Union which promotes democracy, human rights and the rule of law internationally must be prepared to submit its own institutions to independent scrutiny.
That is not a surrender of legal autonomy. It is the practical expression of accountability.
A long voyage towards a single European legal space
EU accession to the European Convention on Human Rights has been discussed since the 1970s. The legal architecture is intricate, and the competing institutional concerns are genuine.
Nevertheless, the central principle is relatively straightforward: no public authority exercising extensive regulatory power should remain outside an effective system of external human-rights review.
Opinion 1/25 may determine whether Europe is finally ready to complete that architecture. Accession will not eliminate every difference between Luxembourg and Strasbourg, nor should it. It would, however, bring the EU within the same external human-rights framework to which all its Member States already belong.
After decades of negotiation, Europe may at last be approaching the point where its commitment to fundamental rights is matched by an equally comprehensive system of accountability.