Turkish prosecutors issued detention warrants for 189 lawyers in İstanbul in June 2017 as part of investigations targeting alleged links to the Gülen movement, with 74 lawyers detained in the initial phase of the operation.
The lawyers were accused of using ByLock, an encrypted messaging app that Turkish authorities treated as evidence of affiliation with the movement after Turkey’s July 15, 2016 coup attempt.
Police units from the anti-terror, organized crime and public order branches raided more than 20 addresses in several İstanbul districts, including Üsküdar, Kadıköy, Tuzla, Zeytinburnu and Eyüp.
Those detained were taken for medical checks at Haseki Training and Research Hospital before being transferred to İstanbul Police Department headquarters on Vatan Avenue.
The Gülen movement is a transnational civic initiative inspired by Islamic scholar Fethullah Gülen.
Ankara designates the movement as a terrorist organization and blames it for the coup attempt. The movement denies involvement in the coup attempt or any terrorist activity.
ByLock became one of the most widely used tools in post-coup prosecutions, with prosecutors frequently citing alleged use of the app as evidence of membership in the movement.
Defense lawyers and rights advocates challenged the reliability and legal value of ByLock data, arguing that alleged app use was often treated as decisive evidence without adequate examination of content, context or individualized conduct.
The warrants against lawyers were part of the broader post-coup crackdown on the legal profession, which included detentions, prosecutions and dismissals targeting attorneys, judges and prosecutors.
The operation also raised concerns about defendants’ access to independent legal representation, since lawyers themselves were increasingly being targeted in the same category of investigations as their clients.
