The European Court of Human Rights (ECtHR) ruled on Tuesday that Turkey violated the right to a fair trial of 591 people convicted of terrorism-related charges over alleged links to the faith-based Gülen movement.
In its unanimous judgment, the Strasbourg court found violations of Article 6 of the European Convention on Human Rights (ECHR), which protects the right to a fair trial, citing the Turkish courts’ treatment of ByLock, an encrypted messaging application, as evidence in the applicants’ convictions.
The 591 applicants had been convicted of membership in an armed terrorist organization over alleged links to the Gülen movement in the aftermath of a coup attempt in July 2016. The ECtHR said that although the evidence differed from case to case, Turkish courts had treated use of ByLock as sufficient on its own to establish the elements of the offense.
ByLock, once widely available on Apple’s App Store and Google Play, was considered by Turkish authorities as a secret communication tool by members of the Gülen movement.
Turkish President Recep Tayyip Erdoğan has targeted the faith-based Gülen movement, inspired by Muslim cleric Fethullah Gülen, who died in 2024, since corruption investigations in December 2013 implicated Erdoğan as well as some members of his family and inner circle. He dismissed the probes as a Gülenist conspiracy and designated the movement as a terrorist organization in May 2016, intensifying a sweeping crackdown after the coup attempt in July of the same year that he accused Gülen of orchestrating. The movement denies involvement in the coup attempt or any terrorist activity.
The ECtHR said the cases raised the same fundamental problem identified in its 2023 Grand Chamber judgment in Yüksel Yalçınkaya v. Türkiye, in which Turkish courts treated ByLock use as conclusive proof of membership in a terrorist organization while failing to provide defendants sufficient safeguards to effectively challenge the ByLock evidence against them.
In Yalçınkaya, the ECtHR found violations of the rights to a fair trial, no punishment without law and freedom of association. The court said Turkish courts had effectively equated ByLock use with knowingly and willingly belonging to a terrorist organization without separately establishing the intent required for the offense, creating an almost automatic presumption of guilt.
The Yalçınkaya judgment has since served as the basis for ECtHR rulings finding similar violations in thousands of cases stemming from Turkey’s post-coup prosecutions.
The applicants also complained under Article 7 of the convention, which prohibits punishment without law, arguing that their convictions were based on an unforeseeable interpretation of the offense. The ECtHR did not examine those complaints separately, saying its finding of a fair trial violation would allow the applicants to seek retrials in line with the principles established in Yalçınkaya.
The court did not award compensation, saying the finding of a violation was sufficient. It said reopening the applicants’ cases, if requested, would in principle be the most appropriate remedy, provided the new proceedings complied with the judgment.
According to the latest figures from the justice ministry, more than 127,000 people have been convicted of alleged links to the movement since 2016, with 10,485 still in prison and legal proceedings ongoing against 83,404 individuals.
In addition to the thousands who were jailed, scores of other Gülen movement followers had to flee Turkey to avoid the government crackdown.
