This judgment, *Kılıçarslan and Others v. Türkiye* (2026), concerns 595 applications from individuals convicted of membership in the “FETÖ/PDY” armed terrorist organization following the 2016 coup attempt in Türkiye. The core issue is that these convictions were based primarily on the applicants’ use of the encrypted messaging application “ByLock,” which domestic courts treated as sufficient, conclusive proof of membership. The European Court of Human Rights (ECtHR) found that this approach effectively imposed objective liability, violating the principle of legality. The Court ruled that the domestic courts failed to provide adequate procedural safeguards to allow applicants to challenge the ByLock evidence effectively. Consequently, the Court held that there were violations of both Article 7 (no punishment without law) and Article 6 § 1 (right to a fair trial) of the Convention. The judgment confirms that the findings in the landmark *Yüksel Yalçınkaya* case are not isolated but represent a systemic issue in how these cases were handled.
**Structure and Provisions**
The decision is structured as a Committee judgment, reflecting the Court’s established jurisprudence on this specific category of cases. It begins by joining the 595 applications due to their identical subject matter. The Court then addresses the admissibility of the complaints, rejecting the Government’s argument that these cases should be treated as distinct from *Yüksel Yalçınkaya*. The judgment is built upon the precedent set in *Yalçınkaya* and *Demirhan and Others*, maintaining that the uniform, global approach taken by Turkish courts toward ByLock evidence constitutes a breach of the Convention. Unlike previous iterations, this judgment serves as a mass confirmation of the Court’s stance, applying the *Yalçınkaya* principles to a vast number of applicants simultaneously.
**Key Provisions for Legal Use**
For legal practitioners and observers, the most critical provisions are:
* **Article 7 Violation:** The Court reaffirms that using ByLock as the sole, conclusive basis for a conviction under Article 314 § 2 of the Turkish Criminal Code violates the principle of legality, as it imputes criminal liability without requiring proof of the specific constituent elements of the crime.
* **Article 6 § 1 Violation:** The Court identifies a failure in the procedural framework, specifically the lack of safeguards to challenge the integrity and content of the ByLock data, and the failure of domestic courts to provide sufficient reasoning for their decisions.
* **Redress:** The Court clarifies that the finding of a violation is sufficient just satisfaction. It explicitly points to Article 311 § 1 (f) of the Turkish Code of Criminal Procedure, noting that the most appropriate form of redress is the reopening of domestic proceedings in line with the “conclusions and spirit” of the judgment.
* **Scope of Evidence:** While the Court acknowledges that some applicants had other evidence against them (e.g., Bank Asya accounts, union membership), it maintains that the “global approach” of the domestic courts—where ByLock was the decisive factor—tainted the entire trial process, regardless of other supplementary evidence.
**:** This decision is highly significant for the Ukrainian legal context, as it reinforces the standards for fair trial rights and the principle of legality in cases involving national security and mass prosecutions. It provides a clear roadmap for how international human rights standards must be applied when domestic authorities rely on mass-processed digital evidence to secure convictions for membership in organizations deemed terrorist or subversive.
