When Andrei Karlov, the Russian Ambassador to Turkey, was shot dead at the opening of an art exhibition in Ankara on Dec. 19, the declaration of support for “the Syrian jihad” made by his assassin, police officer Mevlüt Mert Altıntaş and captured on film moments after the killing appeared to provide a perfectly credible motive: revenge against Russia for helping Syrian President Bashar Assad crush the rebellion

But for Turkish President Recep Tayyip Erdoğan, the story was not that simple. Within days, the Turkish leader had announced that Altıntaş had in fact shot the ambassador as part of a plot to derail Turkey’s rapprochement with Russia. It was all part of a plan, he said, devised by the Gülen organisation, an outlawed religious movement led by U.S.-based Turkish Islamist preacher Fethullah Gülen.

The Gülen movement, formerly allied to Erdogan’s conservative Islamist party, is accused of trying to take over the state from within, and when that failed, mounting a military coup in July 2016. Members of the secretive sect have been the main targets of a wide-ranging government crackdown since the failed putsch.

Two years after the assassination, the 650-page indictment on the case comes to much the same conclusion as Erdoğan reached within 48 hours of the assassination. The indictment states that the orders followed by Altıntaş, who was killed by security officers shortly after the attack, came from Gülen, the first suspect out of 28 named in the case.

Yet the picture painted in the indictment is more confusing than conclusive. For a start, there are the details of Altıntaş’s movements before the assassination. After the former riot police officer scouted out the gallery where the hit would take place and prepared the weapon he would use in it, he was filmed donating a package full of Islamic books, including books described as jihadist texts, to a member of a religious group.

That this was the group associated with Nurettin Yıldız, a Sunni scholar, and not the Gülenists, made no difference to the prosecutors’ findings. The indictment states these acts were simply part of a ploy to hide Gülen’s responsibility for the assassination.

In fact, the indictment goes into further detail on Altıntaş’s links to Yıldız, who is known in Turkey for his strict interpretation of Islam, but not for any link to the Gülen movement. Several witnesses have said Altıntaş attended meetings at Yıldız’s Social Fabric Foundation. One of these, Serkan Ozan, was asked whether the former police officer had any links to Gülen. “Definitely not,” he replied.

The file goes on to explain that, through a series of intermediaries linked to the Social Fabric Foundation and other religious associations, Altıntaş made contact with Abdülkadir Şen, a Sunni Islamist academic rumoured in Turkey to have links to the militant jihadist movement al Qaeda. Şen made headlines six days before Karlov’s assassination when he tweeted threats to Turkey’s minority Alevi sect, whom he said would be held accountable if Syria’s mainly Sunni opposition was defeated by Assad, who belongs to a similar sect to Turkey’s Alevis.

The prosecutors who prepared the report put all of this down to an act of misdirection by Altıntaş. The evidence for the Gülenist links they say he intended to conceal is based on a range of witness statements – including from anonymous witnesses and individuals under arrest for links to Gülen – and digital forensics.

The data included in the case file shows that an unknown user attempted to access Altıntaş’s social media accounts through a VPN connection after the assassination and change the passwords.

These findings relating to Altıntaş’s web accounts, including emails bearing greetings in Arabic, were linked to testimony given by Hüseyin Kötüce, a former National Intelligence Organisation (MİT) officer who has admitted his membership of the Gülen organisation.

Kötüce said members of the group had communicated with one another by sharing passwords to email addresses and writing to each other in the saved drafts folder. The prosecutors say this explains how an individual had known a password used by Altıntaş, and had been trying to access his social media accounts using that password. They go on to speculate that this person was Şahin Söğüt, another suspect in the case, though they admit they have no clear evidence of this.

Söğüt, a former employee of the Information and Communication Technologies Authority, Turkey’s state telecommunications regulator, was named by another confessed Gülenist as Altıntaş’s handler. However, Söğüt denies all the allegations made by this witness, who stood to receive a reduced sentence in exchange for his testimony.

Another piece of evidence used to demonstrate Altıntaş’s links to the Gülen community went back to 2012, when he was attending the police academy in Izmir, western Turkey. One of his associates there, Burak Yusmak, is currently on the run having been identified as a Gülen organisation leader at the academy, and Altıntaş is said to have watched videos of speeches by Gülen and attended discussions with his congregation.

It should be noted, however, that until 2016 followers of Gülen had not been criminalised, and for years the group was celebrated by government leaders, including Erdoğan himself. So, there was nothing illegal about attending the meetings or watching the videos at the time, and nobody saw Altıntaş at any of the group’s events after he graduated.

The evidence then turns to three anonymous witnesses, who provide no information directly related to Altıntaş, focusing instead on the Gülen organisation.

In short, out of 650 pages of indictment, none of the evidence linking Karlov’s killer to the Gülen organisation is stronger than speculation. The glaring point not addressed in its pages, meanwhile, is that while the government says Gülenists mobilised on the day of the coup on July 15, 2016 using the ByLock messaging app, there was neither any evidence that Altıntaş had downloaded the app, nor did he participate in the coup attempt.

Altıntaş himself gave a straightforward motive that was captured on camera as the Russian ambassador lay dying. Yet Erdoğan presented the assassination as a conspiracy designed to drive Turkey to war with Russia, and the prosecutors appear to have run with that claim. Two years after Karlov’s killing, the two countries are working closely together, and Turkey has become a willing partner in the Russian policies in Syria that his assassin condemned after pulling the trigger.