NEW YORK (CBSNewYork/AP) — A psychologist testified at a pre-trial hearing Monday that Pedro Hernandez – who admitted killing a 6-year-old New York City boy who went missing 35 years ago – had a sufficient understanding of his Miranda rights.

As WCBS 880’s Irene Cornell reported, prosecutors played a videotape of the psychologist’s examination of Hernandez while the psychologist himself sat on the witness stand. Prosecutors intended to show what Hernandez knew what he was doing when he waived his rights before confessing to Patz’s murder.

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In the videotape, the doctor broke down the Miranda warnings, asking Hernandez: “When you are told, ‘You have a right to remain silent,’ what does that mean?”

After a long pause, Hernandez mumbled, “I could be quiet and not say anything.”

The doctor concluded that Hernandez compared favorably with other pre-trial defendants and their understanding of their Miranda rights.

But Hernandez’s defense attorney, Harvey Fishbein, challenged that claim.

“You’re comparing him to some of the most severely affected people in the criminal justice system, like someone who tells you he met a person from outer space who told him what to do,” Fishbein said.

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The psychologist said he did not agree with Fishbein’s assessment.

A judge is weighing whether to allow the videotaped confession by Hernandez, who admitted choking Etan and dumping his body. The boy vanished walking to school on May 25, 1979. His body was never found.

Hernandez was arrested in connection with the case in 2012, and has pleaded not guilty.

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