Turkish lawyer Murat Akkoç has warned that a reported error in telecommunications records could have caused authorities to misidentify tens of thousands of people as users of ByLock, exposing a fundamental weakness in prosecutions built on government-generated user lists.
Turkish authorities have treated alleged use of ByLock, an encrypted messaging application, as evidence of membership in the Gülen movement. People have been detained, dismissed from public service or prosecuted on the basis of technical connection records, frequently without evidence that they exchanged criminal messages or committed any unlawful act.
Ankara blames the 2016 coup attempt in Turkey on the Gülen movement, a transnational civic initiative inspired by Islamic scholar Fethullah Gülen, and designates the movement as a terrorist organization. The movement denies involvement in the coup or any terrorist activity.
Journalist Müyesser Yıldız reported on September 25 that records supplied by Türk Telekom may contain a data-processing error affecting connections recorded between June 2014 and September 2015. According to her sources, the end times of some mobile internet sessions may have been entered as their start times when the records were converted into tables.
The distinction is critical because mobile carriers assign the same public internet address to multiple subscribers. Investigators must therefore rely on precise timestamps and port information to determine which subscriber was using an address at a particular moment. A shifted timestamp could attribute a connection to the wrong person.
Experts cited by Yıldız estimated that the alleged error could affect approximately 40,000 people. She also reported that the Information and Communication Technologies Authority (BTK) had asked Türk Telekom to reprocess the records.
Akkoç said the allegation reinforced his argument that defendants could not lawfully be prosecuted merely because their names appeared on a centrally compiled list. He urged defense lawyers to obtain the complete technical records, compare the underlying data and ask courts whether their clients might be among those affected by the reported error.
“An erroneous or suspicious record cannot be the basis of a judgment,” Akkoç said.
The warning followed an earlier failure involving Mor Beyin, a software redirection mechanism embedded in unrelated mobile applications. In December 2017, the Ankara Chief Public Prosecutor’s Office acknowledged that 11,480 mobile subscribers had been unknowingly redirected to ByLock-related internet addresses, causing them to be falsely identified as users of the application. The disclosure led courts and prosecutors to review numerous cases. The prosecutor’s announcement documented the 11,480 affected subscribers.
The Supreme Court of Appeals also ruled in March 2018 that carrier-grade network address translation records alone were insufficient to establish knowing and intentional use of ByLock. It said such records had to be matched with a user identification number and other supporting evidence. The ruling addressed the evidentiary limits of connection records.
Akkoç argued that authorities should return to established standards for examining digital evidence. The installation or alleged use of a smartphone application could not itself constitute a crime, he said. Criminal responsibility would require lawfully obtained evidence showing both an individual’s identity and specific unlawful conduct.
