Prosecutors said Serritella, a convicted sex offender, picked up the 15-year-old boy after he met friends.
Tuesday prosecutors played audio clips from a 1998 interview Serritella did with the I-Team's Chuck Goudie, in which he provided numerous details about the crime scene and victim.
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Serritella's sentencing is scheduled for June 19.
Chereck was found strangled on New Year's Day, 1992, in the Linne Woods Forest Preserve in Morton Grove. The crime scene was not far from his family's home in north suburban Skokie. From early on, Serritella was considered a suspect in the case.
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Serritella's trial started Monday. The first witness called by Cook County prosecutors was Chereck's mother Esther, who offered remarkably composed testimony about the death of her beloved, only child who had been strangled with his own scarf. The boy's father, Allan, died even before an arrest was made in his son's death.
Full interview with 1992 murder victim David Chereck's mother
"I wish to do God's work," Serritella told Eyewitness News investigative reporter Chuck Goudie during the '98 interview, when asked why he would sometimes wear a priest's collar even though he was not a clergyman.
"You're a seeker of the truth, and I like that my friend," he told Goudie at the time.
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Despite the exhaustive TV interview in which Serritella provided a litany of details about the night Chereck was last seen alive, he was not arrested for sixteen years. The I-Team was at O'Hare airport in 2014 when Cook County sheriff's deputies brought Serritella back from Los Angeles where he had been living. From his wheelchair, the man whose alias was "Chivas Regal" repeatedly denied being the killer and walked back the specifics he had rattled off years earlier.
During Monday's bench trial at the Cook County courthouse in Skokie, prosecutors called Chereck's four playmates, now grown men, who he was with on the fateful New Year's night 27 years ago.
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The I-Team interviewed several of them over the years, and on Monday once again they reiterated seeing a white four-door sedan with blacked-out windows following them the evening Chereck was last seen alive. Serritella drove such a white car.
During court, the apparently infirmed Serritella watched keenly and took notes, hunched over in his wheelchair.
During opening statements an attorney for Serritella said that there is no physical evidence against him and no eyewitnesses. Two jail inmates expected to testify about incriminating statements made by Serritella are unreliable according to the defense.
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