John Albert Gardner III received two consecutive life terms without possibility of parole for murdering Chelsea King, 17, and Amber Dubois, 14, and a third life term with a 25-year minimum for the attempted rape of Candice Moncayo, a jogger who escaped by smashing him in the nose with an elbow.
Gardner, 31, breathed heavily and cried at times during emotional statements by the girls' parents and Moncayo before Superior Court Judge David Danielsen pronounced the sentence.
(Scroll down to watch the victims' parents address John Albert Gardner III)
Carrie McGonigle, Amber's mother, said there were not enough words to describe her "minute-by-minute agony."
"I've thought often about her final moments," she said of her daughter. "Was she scared? Was she calling my name?"
Addressing Gardner, she said: "Most of all I'm confident that you'll never make it to heaven."
Gardner avoided the death penalty by reaching a plea deal with prosecutors. His guilty plea last month has sparked a far-reaching review of how California deals with sex predators, a campaign that advocates hope to take to Washington and state capitals.
Calls to stiffen penalties for child sex offenders began almost the moment Gardner was arrested Feb. 28, three days after he attacked Chelsea while she was on an afternoon run in San Diego, strangled her, and buried her in a shallow, lakeside grave.
Amid their anger, the girls' parents spoke lovingly of their daughters on Friday.
"Chelsea was everything this man was not," said her father, Brent King. "She was as good as this man is evil."
Impact statements from the families also faulted the justice system for not keeping Gardner confined after an earlier assault on a girl, despite a dire warning in a psychological report. Family members also blamed his mother, Catherine Osborn, who was seated in court.
"She knew what you were capable of and did nothing," said Kelly King, Chelsea's mother.
Gardner served five years of a six-year prison sentence for beating and molesting a 13-year-old girl in San Diego in 2000. He faced a maximum of nearly 11 years in prison, but prosecutors called for six years.
A court-appointed psychiatrist urged the maximum sentence allowed by law. He said in court documents that Gardner was a "continued danger to underage girls" and "an extremely poor candidate" for treatment.
Maurice Dubois, Amber's father, read the report by psychiatrist Matthew Carroll during his impact statement.
He likened his daughter's killer to a mountain lion whose instincts are to stalk and attack. If the zookeeper frees the lion from captivity, he asked, who is responsible for the killings that come after?
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The case has put California's parole system under the microscope.
Gardner lived little more than a football field's length from a San Diego preschool for at least 16 months while on parole from 2005 to 2008. That violated a condition of parole that prohibited him from living within a half-mile of a school.
A corrections department official let him stay until his lease expired in 2006 but no one noticed he was still living there until a year later. The parole board could have sent him back to prison but kept him on parole, where he had six other less serious potential violations.
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Gov. Arnold Schwarzenegger has ordered a state board to review the parole system.
Brent and Kelly King are leading a campaign for "Chelsea's Law" to allow life sentences for some convicted child molesters in California and lifetime electronic monitoring of others. The bill, which cleared its first legislative committee last month, would also ban sex offenders from parks.
Chelsea was a straight-A student who ran on the cross-country team in suburban Poway, played French horn in a youth symphony and was active in her school's peer counseling program.
The discovery of Chelsea's semen-stained clothing during a massive search quickly led authorities to Gardner. Days later, he led investigators to Amber's remains in a remote, mountainous area north of San Diego.
The investigation into Amber's disappearance had gone nowhere since the Future Farmers of America member disappeared walking to school in suburban Escondido in February 2009.
Gardner led authorities to Amber's remains on condition that the information not be used in court. Investigators were unable to independently link him to the crime, and his guilty plea to that murder was a big reason why the death penalty was dropped.
Gardner also pleaded guilty to attempting to rape the jogger on Dec. 27, near the spot where he attacked Chelsea.