NEW YORK (CBSNewYork/AP) — A defense expert in the trial of Pedro Hernandez, the man accused of killing 6-year-old Etan Patz in 1979, says Hernandez may be more vulnerable to making a false confession than the average person.

Dr. Bruce Frumkin testified Friday that Hernandez would be less able to cope with a police interrogation because of his low IQ and mental disorder, WCBS 880’s Irene Cornell reported.

Hernandez emerged as a suspect in 2012 based on a tip and a videotaped confession that prosecutors say was foreshadowed by remarks he made to friends and relatives in the 1980s.

In Hernandez’s videotaped, hourslong confessions, he says he offered Etan a soda to entice him into the basement of the SoHo bodega where he worked. He told authorities he then choked Etan, put the body in a bag and a banana box and dumped it about two blocks away.

But defense attorneys are trying to show the confession was made up by a mentally ill man.

In his testimony, Frumkin described a recent study in which 60 college students went through three interview sessions with police. The cops pretended to have information about them from their families and 70 percent of those college students ended up confessing in detail to felonies they did not commit.

Frumkin said it’s an important study because these are normal college kids. While it doesn’t mean Hernandez didn’t commit the act, Frumkin said he’s at a greater risk of confessing falsely than the average person.

Prosecutors say the confession is accurate.

Meanwhile, defense attorneys are also planning to introduce evidence that suggests longtime suspect Jose Ramos was involved in the case, 1010 WINS’ Juliet Papa reported.

Ramos had been dating the boy’s baby sitter and later served time in Pennsylvania for molesting two other boys.

Authorities said Ramos made incriminating statements when questioned about Etan in the 1980s, though he never confessed to killing the boy.

“It’s pretty clear that the defense has to prove reasonable doubt and one way to prove reasonable doubt is to introduce another suspect,” Lisa Cohen, author of the book “After Etan,” told Papa.

Ramos has denied it, but a civil court found him liable for Etan’s death in 2004 after Ramos stopped cooperating with questioning.

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