NEW YORK (CBSNewYork/AP) — The jury in the trial of Etan Patz’s alleged killer was introduced Monday to the convicted pedophile who had long been suspected in the boy’s disappearance.

A former federal prosecutor, Stuart GraBois, testified that Jose Ramos had confessed to him that he was 90 percent sure Etan was the boy he had picked up for sex on the day the 6-year-old disappeared in 1979, WCBS 880’s Irene Cornell reported.

To gain leverage over Ramos, GraBois threatened to personally revive a sex-abuse charge against him in Pennsylvania.

GraBois told jurors that Ramos laughed at him, saying the prosecutor would never go out to “the boonies” to chase a conviction. GraBois then found the young victims and put together a case that got Ramos locked up for 26 years.

He, however, never got a confession in the Etan Patz case.

The defense hopes to plant reasonable doubt in jurors’ minds about the guilt of Pedro Hernandez, who is on trial.

Hernandez confessed to police in 2012 that he offered Etan a soda to entice him into the basement of the SoHo bodega where he worked. Then, Hernandez said, he choked the boy and dumped him in a box with some curbside trash. Etan’s body has never been found.

Defense lawyers say Hernandez’s confession is fiction, dreamed up by a mentally ill man with a low IQ and a history of hallucinations and fueled by more than six hours of police questioning before Hernandez was read his rights.

Frank Carroll, a former Bronx prosecutor, testified Monday for the defense that that Ramos became a prime suspect in the case 33 years ago.

Ramos had been arrested for allegedly trying to drag two boys into a drain pipe, where he lived in the Bronx.

The prosecutor questioned him about half a dozen photographs he kept of young boys, one of them resembling Etan.

The videotape of that interview was played for jurors. They heard Ramos first claim he didn’t know Etan, but then say he did know a woman who had been his babysitter.

While he has denied killing Etan, a civil court found Ramos liable for the boy’s death in 2004 after he stopped cooperating with questioning.

Etan’s disappearance ushered in a new protectiveness into American parenting. He became one of the first missing children featured on milk cartons. His parents advocated for legislation that created a nationwide law-enforcement framework to address such cases.

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