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Yalçınkaya v. Türkiye: Terror convictions must yield to human rights

Dr Sanna Elfving (left)

Dr Sanna Elfving is a Senior Lecturer at Lincoln Law School, University of Lincoln, the United Kingdom. Her research focuses on European Union law and the European Convention of Human Rights. She has published a co-authored research monograph Gender and the Court of Justice of the European Union (Routledge 2018). She is currently working on a monograph that applies perspectives of queer and feminist lenses to the case law of the European Court of Human Rights in areas of family life, family reunification, and asylum. Sanna is an elected Convenor of the EU and Competition Law subject section of the Society of Legal Scholars (2023-2026). She is also a member of COST Action ‘Transnational Family Dynamics in Europe’ (2022-2026).

Dr Chloë Gilgan (right)

Dr Chloë Gilganis a Senior Lecturer in law at the University of Lincoln. She completed an ESRC-funded Post-doctoral Fellowship at the University of York Law School where she completed her ESRC-funded PhD in 2019 at the Centre for Applied Human Rights. She holds a JD from New York Law School and is a member of the New York State Bar and she holds a BA from Barnard College, Columbia University.  She has presented her research at over 20 national and international conferences, and it has been published in academic journals, blogs and as Written Evidence for the UK Foreign Affairs Select Committee.


The landmark judgment, Yüksel Yalçınkaya v. Türkiye, delivered by the European Court of Human Rights (ECtHR) on 26 September 2023, means Türkiye must address the systemic problem of convicting individuals for terrorism offences based on their use of the ByLock messaging application (Yalçınkaya, § 413). The case concerned the conviction of a former teacher Mr Yüksel Yalçınkaya for his presumed membership of a suspected armed terrorist organisation, the Fetullahist Terror Organisation/Parallel State Structure (FETÖ/PDY), also known as the ‘Gülen movement’, considered by the Turkish authorities to be behind the attempted coup d’état of 15 July 2016 (Yalçınkaya, § 10). Mr Yalçınkaya’s conviction was based primarily on his use of the encrypted messaging application called ByLock, which the domestic courts held was designed for the exclusive use of FETÖ/PDY members (Yalçınkaya, § 1). The ECtHR noted the systemic nature of Türkiye’s violations of the right to a fair trial (Article 6 of the European Convention of Human Rights (ECHR)), to no punishment without law (Article 7 ECHR) and to freedom of association (Article 11 ECHR). As such, the ruling, under Article 46 ECHR (binding force and implementation of judgments) directs Türkiye to take appropriate measures to address these systemic problems, particularly the over-reliance on ByLock as evidence of the intent and commission of terrorist acts. This ruling will have a profound impact on individuals already convicted under the same circumstances and those yet to be prosecuted because, at the time of the judgment, over 8,000 related cases were pending before the ECtHR involving similar complaints against Türkiye (Yalçınkaya, §§ 414-415). With more than 100,000 within Türkiye, this judgment is poised to affect approximately 2 million individuals.



The Grand Chamber of the ECtHR rejected Türkiye’s arbitrary judicial decisions taken against individuals that the authorities consider responsible for the 15 July 2016 coup d’état attempt. The Turkish courts over-relied on the usage of the ByLock app, which they claimed was designed exclusively for FETÖ/PDY members. This is despite the app’s global existence and the authorities’ refusal to disclose any of the potentially incriminating content on the app. Instead, anyone, who downloaded or used ByLock could be charged with membership of a terrorist organisation. Mr Yalçınkaya was arrested on suspicion of being a member of the FETÖ/PDY, and the evidence in his indictment was decided primarily on his alleged ByLock use. Corroborating evidence included his use of an account at Bank Asya, and his membership in the Aktif Eğitim-Sen trade union and the Kayseri Voluntary Educators Association, which were considered to be affiliated with the FETÖ/PDY (Yalçınkaya, § 1). Mr Yalçınkaya was found guilty and sentenced to six years and three months in prison in 2017. The higher domestic courts upheld his conviction, and the Constitutional Court rejected his application in 2019. Mr Yalçınkaya then lodged a complaint against Türkiye with the ECtHR in March 2020. The ECtHR found three main violations.

Violation of Article 7

The ECtHR recognised that the Turkish authorities were dealing with the aftermath of the attempted coup and while Article 15 allows derogation in times of war or other public emergency, it explicitly forbids derogation of Article 7 (Yalçınkaya, § 237). Article 7 requires that an offence has to be clearly defined in both written and unwritten law and personal liability has to be established in the conduct of the person who physically commits the offence (Yalçınkaya, §§ 238 & 242). Even though the crime was clear under Turkish domestic law, this was insufficient as the domestic courts failed to establish that all the requirements of the offence, particularly the necessary intent, had been fulfilled (Yalçınkaya, § 264). Under established domestic case law, there had to be proof that Mr Yalçınkaya had acted knowingly and willingly within the organisation’s hierarchical structure and embraced its objectives (Yalçınkaya, § 184). This was not met as the Turkish courts had equated the mere use of ByLock with Mr Yalçınkaya ‘knowingly and willingly being a member of an armed terrorist organisation’ (Yalçınkaya, § 267). Therefore, his conviction was secured without establishing the presence of all constituent elements of that offence in an individualised manner, in contravention of the requirements under domestic law and the principles of legality and foreseeability that are at the core of the protection under Article 7 (Yalçınkaya, § 267). There was no other evidence to support the presumption as the content of the messages, and the identities of the persons with whom the exchanges had been made, were not considered (Yalçınkaya, § 263). Such an expansive interpretation of the law made an automatic presumption of guilt based solely on the use of ByLock, making it nearly impossible for Mr Yalçınkaya to exonerate himself from the accusations (Yalçınkaya, § 267). Thus, the scope of the offence could not have been foreseen by Mr Yalçınkaya, which contravenes the purpose of Article 7, which is to provide effective safeguards against arbitrary prosecution, conviction, and punishment. As the offence of membership in an armed terrorist organisation under Turkish law is an offence of specific intent, an indispensable condition is that specific subjective elements are present (Yalçınkaya, § 271). Consequently, such an organisation must intend to commit crimes by the use of force and violence, whereas the act of subscribing to a form of ideology, sharing ideas or combining with others to cultivate an interest in an ideology is not sufficient to qualify as terrorism (Parmak and Bakir v Turkey, § 75).

Violation of Article 6

The ECtHR noted that national courts could not use evidence in a manner that undermined the right to a fair trial (Yalçınkaya, § 344). Insufficient safeguards existed to ensure that Mr Yalçınkaya had a genuine opportunity to challenge the evidence against him and conduct his defence in an effective manner and on an equal footing with the prosecution (Yalçınkaya, § 341). The raw ByLock data collected by the intelligence services was not shared with Mr. Yalçınkaya, which prevented him from challenging the validity of the inferences drawn from ByLock use (Yalçınkaya, §§ 334-335). The domestic courts additionally refused to submit the data for an independent examination for verification of its contents and integrity (Yalçınkaya, § 333). Concerns were raised over the reliability of the ByLock data, such as inconsistency between the different ByLock user lists issued by the intelligence services and the number of users identified and eventually prosecuted (Yalçınkaya, § 334). Further deficiencies included the fact that ByLock was downloadable from publicly available application stores or sites until early 2016, for two years before, without any monitoring (Yalçınkaya, § 338). Thus, anyone, not just members of the FETÖ/PDY could use ByLock, and the domestic courts failed to explain this (Yalçınkaya, § 340). Accordingly, the criminal proceedings against Mr Yalçınkaya fell short of the requirements of a fair trial, resulting in a breach of Article 6(1) ECHR (Yalçınkaya, § 346). The Turkish courts and the government failed to explain whether their response was necessary or genuine and proportionate to the emergency situation that could result in valid limitations to Article 6 as derogations under Article 15 ECHR (Yalçınkaya, § 355). Consequently, the Court ruled that any limitations to Mr Yalçınkaya’s fair trial rights were incompatible with his procedural rights under Article 6(1) and had the effect of undermining public confidence in courts in a democratic society (Yalçınkaya, § 355).

Violation of Article 11

Although the Turkish government stated that Mr Yalçınkaya’s membership in a trade union and the Voluntary Educators Association served only as a source of corroboration and had a very limited bearing on the outcome, the judicial authorities’ reliance on his membership of these organisations was sufficient to constitute an interference with his rights under Article 11 ECHR (Yalçınkaya, § 384 & 387).  The interpretation of the Turkish Criminal Code was too broadly applied to Mr Yalçınkaya’s membership of the two organisations as an indication of criminal conduct, especially given that both had been operating legally prior to their dissolution by national legislation on the grounds that they posed a national security threat due to their alleged affiliation with the FETÖ/PDY (Yalçınkaya, § 390). The courts had not explained what the organisations had done to bring about their dissolution or assessed whether Mr Yalçınkaya’s membership of them had involved ‘inciting violence or otherwise rejecting the foundations of a democratic society’ (Yalçınkaya, §§ 391 & 392).

In sum, the Court found violations of Articles 7, 6 and Article 11. A significant aspect of the ruling was under Article 46, whereby the Court ruled that Türkiye must take measures to address the systemic over-reliance on a user’s possession of ByLock as an indicator of criminal intent and conduct irrespective of any incriminating content. This means that the thousands of pending cases are likely to also result in unlawful violations of Convention rights found in Yalçınkaya.

Key Considerations


The ECtHR's ruling on Yalçınkaya marked a pivotal moment concerning convictions related to the Gülen Movement in Türkiye. It highlighted a systemic violation of rights under Articles 6 and 7 (Yalçınkaya, § 414). In light of its magnitude and implications for the Turkish legal system, the legal actions that Türkiye must undertake in response to Yalçınkaya are wide-reaching. First, the fundamental safeguards enshrined in Article 7 cannot be applied less stringently when prosecuting and punishing terrorist offences, even when allegedly committed in circumstances threatening the life of the nation (Yalçınkaya, § 270). Second, Turkish authorities cannot rely on ByLock's use as a presumption of guilt and as evidence of criminal intent and conduct, but they must apply the requisite elements for finding criminal conduct and membership of a terrorist organisation from the existing law. The criteria for establishing the membership of such an organisation is the defendant’s ‘organic relationship’ to the organisation through the ‘continuity, diversity and intensity’ of the attributed acts and the defendant must have acted ‘knowingly and willingly’ within the ‘hierarchical structure’ of the organisation.


Third, individuals convicted based on their purported use of the ByLock must be eligible for retrials. The digital evidence used against individuals must be disclosed so that they can appropriately defend themselves. Where evidence is withheld on grounds of national security, this needs to be done on the instruction of an independent and impartial court, and the decision should be supported by a transparent disclosure of decision-making. The defendant must be afforded an opportunity to conduct a technical examination of the digital materials to uphold the principle of the equality of arms (Turkut and Yildiz, 2024, 28). Additionally, exculpatory evidence, such as deleted material from ByLock, which supports the individual’s defence, must be released (ibid, 31). Time gaps in the ByLock digital records must be investigated to meet due process requirements, and the processing of the ByLock data by the intelligence community must be scrutinised to evidence a chain of custody for reliability and procedural due process (ibid, 32). The Turkish courts must establish an independent expert panel which will scrutinise the quality, reliability, authenticity, and digital forensic integrity of the ByLock evidence and implement safeguards to counterbalance existing disparities (Turkut and Yildiz, 2024, 32).


Finally, special attention should be paid to Article 7 violations of Turkish lawyers, who are prosecuted based on their representation of clients accused of membership of a terrorist organisation (Lawyers for Lawyers, 2023). The membership of lawful organisations cannot be used as evidence of criminal activity when the organisations themselves are not accused of any unlawful or violent acts. This has implications for members of bar associations and academic lawyers who belong to learned societies (ibid, 2023).


The broader implications for the Turkish legal system


The ECtHR noted that Article 46 ECHR holds the force of a constitutional rule in Türkiye. According to Article 90/5 of the Turkish Constitution, international human rights treaties must be granted preferential treatment over domestic law. Consequently, Türkiye must implement Yalçınkaya. Otherwise, it risks exacerbating its declining relationship with the Council of Europe (CoE) (Turkut, 2023). Evidence of this is the reopening of the full monitoring procedure by the CoE Parliamentary Assembly against Türkiye following the coup attempt until ‘serious concerns’ about respect for human rights, democracy and the continuing erosion of the rule of law ‘are addressed in a satisfactory manner’ (Parliamentary Assembly, 2017). Concerns remain also about the dismissals of the members of the Turkish judiciary, which undermine the judiciary’s independence, impartiality and overall capacity to provide an effective remedy for human rights violations (Venice Commission, 2016b). Yalçınkaya implies that judiciary independence is paramount to ensure democracy and respect for civil liberties. It clarifies that national security does not trump individual liberties in times of political emergency. The application of terrorism charges and the restriction of freedom of expression are a deliberate and systematic government policy designed to suppress critical or dissenting voices (European Parliament, 2022, paras 8, 20). Allowing lawyers, academics, and journalists to exercise their profession freely provides for a healthier democracy and society overall.



Turkish authorities and courts must clarify the elements of a terrorist offence in terms that make it foreseeable and compatible with its essence (Parmak and Bakir, § 77). They must also stop ByLock use as an indicator of criminal intent and conduct, and individuals convicted must be eligible for retrial. The electronic data used against defendants, along with any exculpatory evidence, including deleted data, must be disclosed for due process. Authorities should also ensure that electronic data is reliable and fair by disclosing reasons for time gaps and transparency in the chain of custody. Other CoE states should help Türkiye build capacity for complying with the judgment. This may mean recognising that individuals facing trial may qualify for asylum based on persecution on grounds of political opinion or membership of a social group.


To address the most significant and systematic issues at the root of its ‘persistent erosion of human rights’ (Amnesty International 2024), which stem from the erosion of the rule of law and the lack of independent judiciary, Türkiye must implement the recommendations of the Venice Commission (2016a and 2016b). In 2016, the Venice Commission recommended that Türkiye amend the rules concerning judicial appointments. In accordance with European standards, at least a substantive part of the members of a High Judicial Council should be judges appointed by their peers (Council of Europe, 2022). Currently, the Turkish President appoints almost half of the Council of Judges and Prosecutors, the minister of justice, and his/her undersecretary (Oktay Alkan v. Türkiye, § 30).


The Commission has also highlighted the decreasing space for dissenting voices and civil society in Türkiye under the Turkish Penal Code, which permits wide application of excessive penalties to suppress freedom of expression (Article 10 ECHR) (Venice Commission, 2016b, para 123). The Commission’s recommendations include, inter alia, terminating the use of the Turkish Penal Code to punish the critics of the government, the President, and state institutions and organs (ibid, paras 125-127). Additionally, the Commission recommends that Turkish courts apply the elements of Article 314 (Membership to an armed organisation) narrowly. Turkish courts should stop applying Article 314 alongside Article 220(6)-(7) in cases of freedom of assembly, and the government should repeal Article 220(6), which allows the conviction of persons who commit a crime in the name of a terrorist organisation without being a member (ibid, para 128). Article 220(6) allows for the application of more severe penalties than provided for in Article 314 (Amnesty International 2024). Although Türkiye adopted legislative proposals in March 2024 (ibid), they continue to fall short of the necessary human rights standards as outlined by the Venice Commission.


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