On February 23, 2001, David Attias, then 18, ran a stop sign and sped down the 6500 block of Sabado Tarde Road in Isla Vista, hitting nine parked cars and five pedestrians.
Albert Levy, 27, brother to Ruth, was critically injured in the crash, which left him permanently disabled.
In June 2002, a jury convicted David Attias of four counts of second-degree murder, but a week later, he was deemed legally insane.
A month later, he was committed to Patton State Hospital in San Bernardino County.
After spending the past decade in a state hospital, his public defender has been pushing for Attias, now 30, to move to a less restrictive outpatient program.
Superior Judge Thomas Adams granted him a conditional release, saying Attias has changed after years of intensive therapy and medication.
But the prosecutor who fought to keep Attias in jail, says she disagrees.
"He learned over time what to say in order to secure release," Santa Barbara Senior Deputy District Attorney Paula Waldman told KTLA over the phone.
Waldman says Attias has been violent since early childhood, and he has a history of refusing to take his medication.
She fears that history will repeat itself when Attias is free.
"You can't ignore history," Waldman said. "Every scientist will tell you the best predictor of the future is the past."
"He is a violent human being," Waldman insisted. "He strangled his sister at the age of 11 or 12. He was kicked out of kindergarten for choking a child and holding that child over a trash can."
Attias was re-evaluated during a week-long hearing in May.
Mental health professionals said while he was irritable, argumentative and exhibiting sexually inappropriate behaviors, he was no longer a threat to society.
The parents of the young people killed fought to keep Attias locked up.
"A lot of people, unfortunately, could get hurt," said Tony Bordakis, the father of one of the victims. "No, I'm not for him leaving at all."
"I definitely don't think he should be let out. I think he's a very dangerous guy," his wife, Tricia Bourdakis, said.
But after spending 90 days considering evidence that included Attias' own testimony, the judge believes Attias is a different man today.
It wasn't immediately clear when Attias will be released.
Deedrea Edgar, an attorney with the Santa Barbara County public defender's office, said Attias would be intensively monitored.
She said his new facility had not yet been chosen but would be supervised by the state Department of Mental Health's conditional release program.
KTLA was unable to reach David Attias' family for comment.
His father, Dan Attias, is a well-known television director and producer whose work includes "Entourage," "The Sopranos," and "Beverly Hills 90210."