On the night of the coup attempt, Adil Öksüz was apprehended at Akıncılar Air Base from where the F-16 jets that bombarded the civilians took off. He was then revealed to be the Gülenist Terror Group (FETÖ) imam in charge of the Air Force. Until then, Öksüz had been an unremarkable professor of theology at a mid-range university in a small city for years. He had left no traces regarding his affiliation with FETÖ neither in his lectures nor in his private life.

We have been confronted with a unique organizational structure. In this structure, the intra-organizational hierarchy consists of some idiosyncratic codes, and according to these codes, a primary-school teacher can give orders to theology professors or police chiefs. The organization members act like high-level intelligence elements in terms of disguising and organizing their entire lives according to these codes. They also have a special unit named "confidential service" in order to infiltrate the state.

Therefore, the application ByLock is of vital importance to distinguish and identify FETÖ members since this application was specifically created for the use of FETÖ members. ByLock does not enable one to communicate with others through a telephone contact list. To activate the application, it is required to know the code numbers of the person uploading the application and of the people to be contacted with as well as the password of the chat room. Consequently, the application, which has a peculiar reference network, was designed and used solely to serve FETÖ.

Turkish intelligence realized that the organization had a means of secret communication in early 2014 when their communications in other fields were cut. In December 2014, it was found that they communicated via a special application named Bylock. A year later, the Turkish National Intelligence Organization (MİT) provided access to Bylock servers and from December 2015, the archive started to gradually be decoded. About 165,000 out of 230,000 Bylock users have been identified and the works to identify the rest are ongoing.

However, FETÖ realized this flow of information and completely closed the ByLock servers at the end of January 2016. As of February 2016, FETÖ's all secret communication networks were transferred to the program named Eagle. Although MIT deciphered some segments of Eagle, experts say that it is harder to break it since the program's server belongs to Google.

ByLock presents evidence of primary importance within the process of discharging FETÖ members from public institutions. For this reason, a FETÖ member endeavored to create the impression that ByLock is insufficient proof in the FETÖ investigation by talking to a novice or an operational journalist at daily Hürriyet who did not even check other sources or question his remarks.

For instance, he argues that around 10 percent of ByLock users are not FETÖ members. On what grounds does he come up with such a rate? Why does an ordinary person use an application that operates with a special reference system and is not user-friendly? There is no answer to this question.

He also alleged that a part of ByLock users reside in Iran or Saudi Arabia, which is obviously a baseless lie. It is revealed that 98 percent of the message content was sent from Turkey, while the rest was sent mainly from the United States, France and Kyrgyzstan.

Throughout the interview daily Hürriyet conducted with "former" FETÖ member Alparslan Demir, who moved to the United States and changed his name to David Keynes, no counter question was asked to him. So, it is not hard to see that it is an effort to discredit the most important source of evidence in the FETÖ investigation.