Case law • ECtHR
Messaging evidence and a fair trial: Yalçınkaya v. Türkiye
Commentary on the Grand Chamber judgment of 26 September 2023, application no. 15669/20.
The decision
In Yüksel Yalçınkaya v. Türkiye, the Grand Chamber found violations of Articles 7, 6 § 1 and 11 of the Convention. The case concerned a conviction for membership of a terrorist organisation, with substantial reliance on data associated with ByLock. The case’s specific facts and context matter when interpreting the judgment.
Why scrutiny matters
Under Article 6, the Court examined the defence’s lack of access to raw data and insufficient safeguards to counterbalance that restriction. It identified shortcomings in addressing challenges to the integrity and evidential value of the data. The judgment should not be reduced to a rule that all messaging evidence is inadmissible.
Methodological comment
A practical lesson for digital forensics is to explain the origin of material, its transformations and the connection between source records and a report. Reasoning should be traceable, and conclusions dependent on unavailable data should be identified. This is a methodological interpretation of the judgment, not a quotation of a mandatory technical procedure. Polish courts assess evidence within the relevant proceedings; this judgment does not replace analysis of an individual case.
Sources and further reading
Educational material about Polish proceedings and digital forensics. Individual cases require examination of their records. Translations do not change the jurisdiction of the legislation discussed.
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