Later in the trial, other expert witnesses for the defense diagnosed Dahmer with necrophilia, as well as with borderline personality disorder, schizotypal personality disorder, and a psychotic disorder.  Nonetheless, forensic psychiatrist Park Dietz, testifying for the prosecution on  February 12, said he did not believe Dahmer to be suffering from any mental disease or defect at the time that he committed the crimes. Dietz interviewed Dahmer for a total of 18 hours. He says he found the killer personable, pleasant to talk to, and thoroughly cooperative; some of their conversations were a sort of expert-to-expert exchange about things like strangulation. Dietz read hundreds of pages of police reports; transcripts of interviews with Dahmer’s family, friends, and co-workers; and medical reports. He went to the apartment building where Dahmer committed his last string of murders. He observed the places where Dahmer had cruised for victims. Samuel Friedman, an independent psychologist (testifying for neither prosecution nor defense), described Dahmer as, “amiable, pleasant to be with, courteous, with a sense of humor, conventionally handsome, and charming in manner. He was, and still is, a bright young man.” Jeffrey Dahmer was found to be legally sane at his trial.

Listen to Dr. Berlin’s final day of testimony here.