Thornton Sentenced to Death in Murder of Westlake Nurse : Judge Charles McGrath issues the decision after hearing the victim’s 6-year-old son describe the pain he’s suffered since his mother’s slaying.

Mark Scott Thornton, who abducted and killed a Westlake nurse during a 1993 carjacking, was sentenced Monday to death during a hearing in which the victim’s 6-year-old son pleaded with a judge to end the killer’s life.

“All I wanted to say was how I feel about what happened to my mom. It was a very bad thing,” a composed Cliff O’Sullivan Jr. told a hushed Ventura County courtroom, bringing some spectators to tears.

“All I think is that what the bad guy did to my mom should happen to him,” said the boy, who could barely see over the witness stand. “. . . It’s really sad for my family, ‘cause she was one of the greatest mothers I’ve met.”

Thornton, 20, who will be California’s youngest Death Row inmate, bowed his head and avoided making eye contact with the child.

A jury in March recommended a death sentence for Thornton. That same panel in December found him guilty of first-degree murder and a special circumstance that the crime was committed during a robbery and a kidnaping.

Prosecutors, relatives and friends of the victim and even jurors celebrated the death sentence outside court.

“He had a blatant, complete and total disregard for human life,” said Jesse Wilson, one of five jurors who came to see the sentencing. “He killed just to satisfy his own selfish needs. He gave absolutely no mercy to her, and I can’t find one reason to give him mercy.”

Deputy Dist. Atty. Peter D. Kossoris said he feared the judge would not follow the jury’s recommendation.

“I was concerned because I had no way of knowing what he [the judge] would do,” said Kossoris, who had been critical of Superior Court Judge Charles R. McGrath during Thornton’s four-month trial.

Thornton sat quietly through the sentencing for the most part. He choked back tears as one of his attorneys asked the judge to spare the defendant’s life. At other times, however, he showed little emotion.

Deputy Public Defender Susan R. Olson, Thornton’s lead attorney, said she was dejected after the hearing.

“We were hoping that our point of view would prevail,” said Olson, who argued that Thornton did not deserve the death penalty for killing O’Sullivan.

According to court testimony, Thornton abducted 33-year-old Kellie O’Sullivan from outside a Thousand Oaks shopping plaza on the afternoon of Sept. 14, 1993. He drove her up winding roads into the Santa Monica Mountains, where he shot her once in the chest and twice in the back.

Stealing her new Ford Explorer, Thornton drove to Simi Valley and had the name of his ex-girlfriend tattooed on his shoulder. He then kidnaped the girl, 16-year-old Stephanie Campbell, and held her captive before his arrest five days later at a casino in Nevada.

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More than 200 volunteers joined the search for the missing nurse. The Thousand Oaks community was outraged after the nurse’s decomposed body was found in a desolate mountain grotto 12 days after her disappearance.

Thornton’s trial, which lasted six months and involved more than 125 witnesses, was one of the biggest criminal cases in recent Ventura County history.

But after Monday’s sentence, prosecutors and defense attorneys not only disagreed on the outcome--they disagreed on the reason the jury recommended Death Row for Thornton.

Defense attorneys accused the panel of losing its objectivity and identifying with O’Sullivan because she was a random crime victim from the suburbs.

“She became sort of the totem figure as the ideal, middle-class woman: a white female, a nurse and a mother,” said Olson, who unsuccessfully tried to persuade the judge to reduce Thornton’s sentence to life in prison without parole.

“If this [murder] had happened to someone in inner-city Los Angeles, my guess is that this would have been plea-bargained for life in prison without parole,” Olson said.

And in court, Deputy Public Defender Howard J. Asher told McGrath that the death-penalty recommendation was a result of the “frustration and anger and hatred they [jurors] felt toward Mark Thornton.

“The jury did from their perspective what they thought was right,” Asher said, as several jurors in the audience shook their heads in disagreement. “It is our view, and it has always been our view, that the evidence doesn’t support a death verdict.”

Prosecutor Kossoris cited the circumstances surrounding the nurse’s death--including the fact that Thornton got a tattoo after the killing--as the main reason the death sentence was the right verdict.

The evidence, Kossoris told the judge, shows that Thornton has a “cowardly, cold, depraved attitude.”

Thornton, who has said that his lawyers kept him from testifying, against his will, did not ask on Monday to make a statement.

McGrath agreed with prosecutors. The judge said Thornton was motivated to kill O’Sullivan so that he would have more time to commit other crimes--namely, kidnap his ex-girlfriend--before the police would start looking for him. He also said Thornton caused additional trauma for the victim’s family by killing her in a mountainous area where the body would not be found for days.

“That death is warranted is overwhelmingly supported by the evidence,” the judge ruled.

In addition to testimony from the boy, O’Sullivan’s mother, ex-husband, and the former husband’s cousin gave statements about how they have been impacted by her death.

The mother said her daughter was not perfect, but that she would not have ever left her son alone. “I lost my daughter in a coldblooded act of murder,” Sharlene Cunningham said.

Cliff O’Sullivan Sr. called Thornton “nothing but a liar and an assassin.”

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Outside court, O’Sullivan said he was pleased with the sentence. “It went exactly how I hoped it would,” he said.

He also said his young son felt that he helped his deceased mother by making a statement at her killer’s sentencing.

“He felt comfortable saying what he wanted to say, and I agree with him,” the father said.

McGrath ordered Thornton transferred to San Quentin within 10 days. Prosecutor Kossoris said he expects it will be several years before Thornton’s appeals process begins.

As for Thornton’s execution, the prosecutor noted that only two of the more than 400 convicts sentenced to Death Row since capital punishment was reinstated in California in 1978 have been executed.

“If you go by what’s happened in the past, there’s no end in sight,” said Kossoris, who has now prosecuted four Death Row inmates.

Times correspondent Andrew D. Blechman contributed to this report.

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Thornton becomes ninth man from Ventura County sent to death row. B6

(BEGIN TEXT OF INFOBOX / INFOGRAPHIC)

Son’s Courtroom Plea

Cliff O’Sullivan Jr., the 6-year-old son of slain Westlake nurse Kellie O’Sullivan, took the witness stand Monday before his mother’s killer was sentenced to death. His words brought tears from some of the spectators in the courtroom.

’ My name is Cliff, and my mom is Kellie. All I wanted to say was how I feel about what happened to my mom.

It was a very bad thing. And all I think is that what the bad guy did to my mom should happen to him, I think, too.

And how much pain he put me into with my family--even my mom, even that she is not alive.

It’s really sad for my family, ‘cause she was one of the greatest mothers I’ve met. Thank you. ‘