Anatoly Onoprienko, Citizen O
The day after the initial interview with Onoprienko, Teslya went to Lviv, where Onoprienko had been moved, and began a 5-day series of one-on-one interviews with his suspect. Teslya called Onoprienko "the most perplexing person I've ever interviewed." The suspect told Teslya he was commanded by God to kill, and that he had been "chosen" as a superior specimen. He claimed he could wield strong hypnotic powers, control animals through telepathy and stop his heart with his mind. "I told him that I thought his hypnotic powers were interesting, and asked him, for my benefit, if he could try them on me," Teslya said. "But he said that it only worked with weak people, and I wasn't a weak enough person."
Onoprienko revealed that he had previously spent time in a Kiev hospital for schizophrenia, a lead that Teslya, as an Lviv investigator, was not allowed to pursue. The statement was interesting because immediately following the arrest, Kiev Interior Ministry investigator Alexander Tevashchenko said that Onoprienko - then identified as "Citizen O" - was an outpatient whose therapists knew he was a killer. Teslya later stated that he knew nothing about that side of the case, and the Kiev investigators have yet to release any further information regarding it since the initial statement.
On Friday, April 19, 1996, the investigation was taken out of Teslya's hands and turned over to federal Interior Ministry investigators. When his week of questioning the suspect was over, Teslya said he had concluded Onoprienko was genuinely insane and had acted alone. "There have been many rumors that he was part of a gang, but my feeling is that his discussions of his motives, and of his special powers, were not fabricated. I can be wrong, but that's what I think," he said. "Plus, just thinking rationally, I don't think anyone but a single killer could have pulled off so many murders. In a gang, someone talks, another drinks, a third whispers something to a girlfriend, and it's all over…but as I say, I can be wrong."
Even though psychiatrists declared Anatoly Onoprienko mentally fit to stand trial, the proceedings did not begin until November of 1998. Incredibly, trials in the Ukraine cannot begin until the defendant has read all the evidence against him, at his leisure, and in the case of Anatoly Onoprienko there was plenty to get through - 99 volumes of gruesome photos, showing dismembered bodies, cars, houses and random objects Onoprienko stole from his victims. Another reason for the delay was money. It was not until the head judge in the trial made a televised appeal that the Ukrainian government agreed to allocate the necessary funds for a lengthy trial.
On November 23, 1998, a Ukrainian court ruled that 39-year-old Anatoly Onoprienko was mentally competent and could be held responsible for his crimes. The regional court in Zhytomyr said that Onoprienko, "Does not suffer any psychiatric diseases, is conscious of and is in control of the actions he commits, and does not require any extra psychiatric examination."