Deputy District Attorney Dawn Bladet warned the jury Wednesday, warned everyone in the courtroom, "you can't attach your own morality, your own thought process, to that man," referring to Richard Joseph Hirschfield, who sat in the defendant's chair.

She showed pictures of the slashed throats of the two teenage UC Davis freshmen. She told the story of a man's escalating violence and deviance, ready to rape and prepared to kill.

But there was a whole other level of sickness to Hirschfield, Bladet said, an element not yet fully explained until she explored it with the Sacramento Superior Court jury in the first round of her closing arguments in the defendant's murder trial.

Bladet described Hirschfield as more than a typical rapist-murderer. She attributed to him a special kind of perversion in which he obtains gratification not just through his sexualized violence on the women he terrorizes and controls, but also through his manipulation – his "toying," the prosecutor called it – of the female victims' male companions whom he kept at his mercy, too.

"He didn't just pick a vulnerable woman on the side of the street," the prosecutor said of Hirschfield's alleged Dec. 20, 1980, abduction of UC Davis sweethearts Sabrina Marie Gonsalves and John Harold Riggins. "He picked a couple. It's part of what he likes – the degradation of the woman in front of her man, having an audience to his crimes."

The proof, Bladet said, was right there in the duct tape. Hirschfield "mummy-wrapped" Gonsalves' head in it, according to the prosecutor, leaving her no way to breathe after he raped her, then slit her throat.

But in Riggins' case, Bladet said that Hirschfield left the silver tape wrapped around his head just loose enough, slightly opened around his lips, so the young man would stay alive while the defendant sexually assaulted and then savagely murdered Riggins' girlfriend.

"Why do you think he left John so he could breathe?" Bladet asked the jury. "So he could live long enough to hear what was happening to the one he loved. He let him breathe. He can't see. He's tied up. He can't protect his girlfriend. He can't do anything to stop it. But he's left him alive so that he has to hear it, has to know what's happening."

Bladet said "that's the sickness" that defines Hirschfield, "the unspeakable and the incomprehensible."

Hirschfield's three-person defense team gets its chance to tell the jury its story today of why they believe their client is innocent.

Their arguments and Bladet's rebuttal are expected to run through Friday. The jury will then begin deliberations, if all of the presentations are completed.

The 63-year-old defendant is accused of two counts of murder in the slashing and bludgeoning deaths of Gonsalves and Riggins, both of whom were 18 when they were abducted after working on a presentation of the Davis Children's Nutcracker at the Veterans Memorial Theater. Their bodies were found two days later in a ravine near Lake Natoma.

Along with multiple murder, Hirschfield is charged with special-circumstance allegations of rape, kidnapping and oral copulation.

If the jury convicts Hirschfield and finds the allegations to be true, the trial will then proceed to the penalty phase, where Judge Michael W. Sweet's sentencing options would be capital punishment or life without parole.

In her summation, Bladet kept bringing the jury back to the key evidence in the case – a semen-stained blanket found in the van Riggins drove the night of the killings. DNA testing identified Hirschfield as a one-in-240 trillion match, a state Department of Justice criminalist testified.

Bladet ran through key corroborating evidence she said backed up the DNA. It included: Hirschfield's prior history as a sex criminal, including a 1975 rape in Mountain View where a young man also was present; a suicide note his brother wrote, putting the sibling at the scene of the couple's deaths; the defendant's connections to Davis and a sighting of him in the college town after his July 1980 parole; and his familiarity with the area where the bodies were discovered through his late brother's residence at a trailer park in Rancho Cordova.

The prosecutor discounted the case the Yolo County DA filed on four defendants exonerated 20 years ago by the DNA results. She placed blame for the botched prosecution on an inexperienced Davis police detective and a lying informant who played the cop for a $30,000 cash reward.

Riggins and Gonsalves, Bladet said, were just a couple of young people involved in their first serious relationship, "completely innocent at a time of hope and innocence, Christmastime." The two were headed to a birthday party for Sabrina's sister after the play, when they disappeared.

They spent their last day making Christmas cookies. They were bringing the ice cream to the party when "they were snatched out of nowhere," Bladet said – victims of society's worst fears about the worst people in its midst.

"The terrifying nature of the crimes (Hirschfield) committed, for the community, ... is the fact that this is the kind of crime – it can't be predicted," Bladet said. "It can't be prevented. You can't protect yourself, and that's what terrifies people, to think there are human beings who walk among us like Richard Hirschfield who can do what he did and the way he did it to these two young people."

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