A Tale of Two Courts: the relationship between the Court of Justice of the European Union and the European Court of Human Rights

1.  A tale of two courts.

The process of European integration has given rise to two parallel institutions with overlapping membership: the European Union (EU) and the Council of Europe (CoE). While the EU initially focused on economic cooperation, the CoE was established as the regional human rights watchdog, primarily through the European Convention on Human Rights (ECHR) and its Strasbourg-based Court (ECtHR).

However, the Court of Justice of the European Union (CJEU), based in Luxembourg, has developed fundamental rights as part of EU law through its case law. Furthermore, successive treaty reforms have reinforced the CJEU’s role in human rights protection, a shift cemented when the Charter of Fundamental Rights (CFR) became legally binding in 2009.

This has led to a potentially problematic situation, as the CFR is only to be interpreted by the CJEU, while the ECHR’s interpretation depends on the ECtHR. Both treaties recognise similar — yet different — rights, and Member States of both organizations are expected to respect the rulings of both courts.

In order to prevent potential contradictions, several steps have been taken to promote coherence among the case law of both courts. A major step in this direction is the provision of Article 6(2) of the Treaty of the European Union (TEU), which states that “the Union shall accede to the European Convention for the Protection of Human Rights and Fundamental Freedoms. Such accession shall not affect the Union’s competences as defined in the Treaties.” 

Following this provision, the European Commission and the CoE prepared the 2013 Draft Agreement. This document scrutinised the conditions under which the EU would accede to the ECHR. However, in Opinion 2/13, the CJEU relied on article 344 TFEU to determine that the agreement could grant the ECtHR jurisdiction to interpret the division of competences in the EU, a role it deemed exclusive to Luxembourg (Łazowski & Wessel, 2015, p. 198). A revised agreement was drafted in March 2023 to address the CJEU’s concerns (Øby Johansen et al., 2024, p. 646), but it is yet to be seen whether this third time’s a charm.

Consequently, the current interaction of both courts is governed by a series of principles derived from case law and succinct legal provisions, such as article 52(3) CFR, as well as by regulations and directives with a direct impact on fundamental rights. The aim of this article is to explain these principles and delve into the CJEU’s scepticism towards the use of the ECtHR’s case law in its judgements.

2. Principles governing the EU and CJEU’s relations with the ECtHR.

The relation CJEU-ECtHR is governed by several principles derived from the case law of both tribunals. The ECHR and the CFR “are not two autonomous systems separated by a watertight fence” (Callewaert, 2023, p. 335). Thus, they should shed some light on how their legal orders interplay. 

On the one hand, the ECtHR’s approach to the EU has been problematic since the latter, as a sui generis organisation, is not part of the ECHR. As such, the ECtHR is not entitled to examine the EU acts’ compliance with the Convention. This may raise an issue whenever Member States breach the rights contemplated in the ECHR when enforcing EU law. In the Bosphorus case, the ECtHR examined whether the impoundment of a Turkish aircraft by Irish authorities in compliance with EU regulations implementing UN sanctions against former Yugoslavia violated its right to property. The ECtHR determined that, if a State takes actions applying an organisation’s binding instructions, these would be justified if said organisation is considered to provide fundamental rights’ protection equivalent to that of the ECHR. Therefore, if the organisation is considered to provide an equivalent protection (as it is the case of the EU), “the presumption will be that a State has not departed from the requirements of the Convention when it does no more than implement legal obligations flowing from its membership of the organisation” (Bosphorus Hava Yolları Turizm ve Ticaret Anonim Şirketi v. Ireland, para. 156).

However, the principle of equivalence may not apply directly when EU law grants Member States discretion in implementation and lacks CJEU judicial review (Ippolito & Velluti, 2014, p. 176). This has been the case with several EU directives, especially those regarding the Dublin asylum system. In M.S.S. v. Belgium and Greece, the ECtHR rebutted the equivalence presumption. In this case, M.S.S. was an asylum applicant whose application should’ve been examined by the Greek authorities according to the Dublin regulation, as Greece was the first point of irregular entry. Therefore, the Belgian authorities had him transferred to Greece. However, the ECtHR ruled that Dublin transfers must be suspended if the sending state is aware of serious deficiencies in asylum procedures and reception conditions (ibid, p. 177). The Court was not assessing Belgium’s compliance with the Dublin regulation, but rather considering that the transfer to Greece, may it be in accordance with EU law, meant exposing the asylum applicant “to conditions of detention and living conditions that amounted to degrading treatment” (M.S.S. v. Belgium and Greece, para. 367) thus violating Article 3 of the ECHR.

In sum, the ECtHR seems to consider EU law as providing an equivalent protection to that given by the ECHR. However, when there is room for manoeuvre for Member States, they  must ensure that their actions  abide by the requirements of the Convention. This is especially the case when there might be a potential breach of imperative rights, such as the prohibition of inhuman or degrading treatments.

On the other hand, the CJEU’s approach to the ECHR and the Strasbourg court has evolved over the decades. Before the CFR became binding, the CJEU relied largely on the ECtHR’s case law to shape fundamental rights in EU law. These references were so common that the Court at times seemed to treat them as more than mere inspiration (Tinière, 2023, p. 324). At this time, the CJEU considered the ECtHR’s case law to be “guidelines which should be followed within the framework of Community law” (Ippolito & Velluti, 2014, p. 165). 

This role of the ECtHR’s case law and the ECHR itself as a special source of inspiration has also been crystallized in the CFR. Article 52(3) states that the rights included in the CFR with corresponding rights in the ECHR must at least respect the meaning and scope of the Convention, without prejudice to the possibility of EU law raising the levels of protection.

Furthermore, this walkway between EU law and the ECHR is also found in an array of European regulations and directives, mainly those relating to asylum issues, given the ECtHR’s extensive case law on this matter. For example, article 4(1) of the Return Directive allows for the application of the ECHR when its rules are more favourable to the third-country national than those of the Directive itself (Molnár, 2021, p. 260).

In light of the above, the ECHR acts as a yardstick when assessing EU law and acts’ compliance with fundamental rights. However, despite these legal provisions, the CJEU has developed “a rather EU-law centred argumentative strategy which, at first sight, does not genuinely engage with the ECHR and relevant ECtHR judgements” (Molnár, 2021, p. 261). This has been mostly the case ever since the CFR’ acquisition of binding nature, which has triggered the CJEU’s quest for autonomy.

3. The CJEU’s quest for autonomy.

When the CFR became binding, the CJEU developed a more sceptical approach to the use of ECtHR’s case law in its own resolutions. The Luxembourg court’s references to Strasbourg’s precedents do not follow a predictable pattern (Callewaert, 2023, p. 338) and appear to be instrumental to Luxembourg’s needs in each case. It appears that the CJEU will refrain from referencing Strasbourg rulings when it seeks autonomy, while it will use them when it is in need of legitimacy. 

Regarding the search for autonomy, the CJEU is not a human rights court such as the ECtHR, as the interpretation of European fundamental rights is not its only task. In fact, its duty is “to protect EU law from the law of the Member States and international law” (Tinière, 2023, p. 327). Therefore, it is only natural that whenever possible, the CJEU prefers to lean on the CFR and its own rulings to interpret the meaning and scope of fundamental rights. This quest for autonomy has several manifestations.

Firstly, the CJEU has used key notions from the Convention several times but slightly modified its phrasing (Callewaert, 2023, p. 340). For example, in Staatssecretaris van Justitie en Veiligheid (Éloignement – Cannabis thérapeutique), the CJEU established that the applicable test to the expulsion of severely ill people consists in determining whether there is “a real risk of significant reduction in his or her life expectancy or a rapid, significant and permanent deterioration in his or her state of health, resulting in intense pain” (para. 66). However, the ECtHR phrased it differently in Paposhvili: “a real risk of being exposed to a serious, rapid and irreversible decline in his or her state of health resulting in intense suffering or to a significant reduction in life expectancy” (Paposhvili v. Belgium, para. 183). Although there may not be any substantial differences, “the result is nonetheless some ambiguity instead of legal clarity” (Callewaert, 2023, p. 340) and creates an image of autonomy, despite clearly drawing on Strasbourg’s case law.

Secondly, even when the CJEU uses the ECtHR’s case law, it tends to do so only once, with “all subsequent references being made by the CJEU only to its own case law which has incorporated that piece of Strasbourg case law” (ibid, p. 341). In consequence, both courts’ rulings have an identical content, but the CJEU maintains an appearance of autonomy.

Lastly, it is worth noting those cases in which the CJEU adopts an argument primarily focused on EU law, seemingly avoiding direct engagement with the ECHR and ECtHR jurisprudence (Molnár, 2021, p. 261). This has been the case with the interpretation of the Return Directive relating to third country nationals. The ECtHR has extensive case law relating the principle of non refoulement and the due treatment of irregular immigrants. The Advocate Generals seem prone to referencing these existing precedents in their opinions, but they rarely make it into the final CJEU’s judgement. However, solutions remain largely equivalent, which suggests that “ECtHR case law does play a role behind the scenes in CJEU’s deliberations but does not surface in the judgements themselves” (ibid, p. 275). This is even more common when the CJEU has extensive previous case law on the matter, thus it tends to be self-referencing.

However, these practices – modifying key legal formulations and selectively citing ECtHR case law – can create legal ambiguity, as they obscure the extent to which the CJEU aligns with ECtHR jurisprudence. By doing so, the CJEU preserves flexibility to highlight differences between CFR and ECHR rights in the future, thus minimizing the application of Article 52(3) CFR. While this approach reinforces EU law’s autonomy, a more structured engagement with ECtHR case law – even if aimed at differentiating interpretations and non-correspondent rights – could enhance legal clarity and predictability without compromising judicial independence.

On the contrary, when the CJEU faces the interpretation of a poorly explored fundamental right or a well-established right that is being seriously challenged by Member States, it tends to rely on ECtHR’s case law in order to legitimate its statements (Tinière, 2023, p. 327). This happened in Commission v. Hungary (transparency of associations), when the Luxembourg court had to interpret freedom of assembly in the CFR. As it was the first time the CJEU could provide a deep interpretation of this right, it resorted to Article 52(3) of the CFR to determine that there was a correspondent right in the ECHR and interpret it in light of its case law. Additionally, in Commission v. Poland (régime disciplinaire des juges), the CJEU largely applied ECtHR’s case law when interpreting the right to an impartial tribunal established by law, as “a way for CJEU to reinforce its position and recall that this is supported by the ECtHR” (ibid, p. 329). 

4. The way forward.

The relationship between the CJEU and the ECtHR’s case law remains chaotic and inconsistent. This framework sheds some light over the CJEU’s approach to the ECtHR’s case law, but it is not exhaustive. Other explanations have been offered by scholars, such as the inherent inconsistencies in judgement-drafting (Tinière, 2023, p. 330) or the explicit references to the ECHR in EU secondary law.

The key issue is its impact on human rights protection in Europe. Although the CJEU has occasionally set lower standards than the ECtHR—as seen in N.S. and Others compared to M.S.S.—both courts generally provide equivalent protection. However, the instrumentalization of Article 52(3) CFR and the inconsistent use of ECtHR rulings fuel legal uncertainty. A direct clash remains possible, particularly in cases where the ECtHR considers certain rights absolute, while EU law allows exceptions, such as in terrorism-related expulsion cases.

To avoid such conflicts, and given the CJEU’s reluctance toward EU accession to the ECHR, informal judicial coordination must play a central role in shaping their relationship. However, this largely depends on the judges’ willingness to engage in dialogue. Consequently, it would be necessary to formalise these communication channels and further develop Article 52(3) CFR to ensure that, while preserving the autonomy of EU law, the CJEU is systematically required to consider ECtHR jurisprudence. This could also help clarify key legal concepts in rulings, enhancing legal certainty and coherence between both legal orders.

5. Bibliography.

Bosphorus Hava Yolları Turizm ve Ticaret Anonim Şirketi v. Ireland, App. No. 45036/98 (June 30, 2005). Available at:  https://hudoc.echr.coe.int/fre#{%22itemid%22:[%22001-69564%22]} [Accessed 20/01/2025]

Callewaert, J. (2023) Convention control over the application of Union law by national judges: the case for a wholistic approach to fundamental rights. European Papers 8(1), 331-347. http://doi.org/10.15166/2499-8249/655 

CJEU. Judgement of 22 november 2022. Staatssecretaris van Justitie en Veiligheid (Éloignement – Cannabis thérapeutique), C-69/21, ECLI:EU:C:2022:913. 

European Union (2010). Charter of Fundamental Rights of the European Union. In Official Journal of the European Union C83 (Vol. 53, p. 380).

Ippolito, F. & Velluti, S. (2014) The relationship between the ECJ and the ECtHR: the case of asylum. In Dzehtsiarou, K., Konstadinides, T, Lock, T. & O’Meara, N. (eds.) Human Rights Law in Europe: The Influence, Overlaps and Contradictions of the EU and the ECHR, 156-187. Routledge.

Łazowski, A., & Wessel, R. A. (2015). When Caveats Turn into Locks: Opinion 2/13 on Accession of the European Union to the ECHR. German Law Journal, 16(1), 179–212. http://doi.org/10.1017/S2071832200019477. 

M.S.S. v. Belgium and Greece, App. No. 30696/09 (January 21, 2011). Available at: https://hudoc.echr.coe.int/fre#{%22itemid%22:[%22001-103050%22]} [Accessed 30/01/2025] 

Molnár, T. (2021) The impact of the ECtHR case-law on the CJEU’s interpreting of the EU’s return acquis: More than it first seems? Hungarian Journal of Legal Studies 62(4), 257-280. http://doi.org/10.1556/2052.2022.00354. 

Øby Johansen, S., Ulfstein, G., Follesdal, A. & Wessel, R.A. (2024) The revised draft agreement on the accession of the EU to the ECHR: third time’s a charm? European Papers 9(2), 641-646. https://doi.org/10.15166/2499-8249/774. 

Paposhvili v. Belgium, App. No. 41738/10 (13 December, 2016). Available at: https://hudoc.echr.coe.int/fre?i=001-169662. [Accessed 31/01/2025]

Tinière, R. (2023) The Use of the ECtHR Case Law by the CJEU: Instrumentalisation or Quest for Autonomy and Legitimacy? European Papers 8(1), 323-330. http://doi.org/10.15166/2499-8249/654.