ECHR, 23 June 2026 – Çali and 263 others v. Turkey (breach of Article 6(1))

Further systemic finding of violation regarding prosecutions based solely on possession of the “ByLock” application

The case concerns the convictions handed down against 264 applicants for membership of an armed terrorist organisation described by the Turkish authorities as the ‘Fethullahist terrorist organisation / parallel state structure ’ (“FETÖ/PDY”), which the authorities regard as being behind the attempted coup that took place in Turkey on 15 July 2016.

In a judgment of 23 June 2026, the ECHR confirmed and expanded upon its Yalçınkaya case law (GC, 2023) by once again finding Turkey at fault in a large-scale case (involving more than 260 applicants), including our client Mr Hüseyin Özyurt.

Key points:

A structural violation of the right to a fair trial (Art. 6(1) of the ECHR)

The Court found that the Turkish courts had adopted an automatic and blanket approach: the mere use of the encrypted ByLock application was regarded as sufficient evidence of membership of a terrorist organisation. However, the ECHR found:

• the absence of adequate procedural safeguards regarding the collection and use of ByLock data
• the practical impossibility for the accused to challenge the evidence
• insufficient reasoning in the domestic decisions

Conclusion: an infringement of the very essence of the rights of the defence.

Confirmation of the systemic nature of the violations

Key point of the judgment: the Court emphasises that the violation is not linked to isolated cases but stems from a widespread judicial practice concerning ByLock; all convictions based on this pattern are affected.

Key practical consequence: possible reopening of criminal proceedings in Turkey

The Court emphasises the key point for practitioners: the reopening of domestic proceedings constitutes the primary remedy, pursuant to Article 41 of the ECHR.