The boy, who has not been publicly identified because he is a minor, was remanded to house arrest and will wear an ankle monitor while he awaits sentencing. He is expected to return to court on June 30 for a disposition setting hearing.
"What we want, as far as justice is concerned, we want him to go to prison and understand the consequences of his doing," said the uncle of the victim, Monique Muñoz, outside the courthouse on Friday. "I want his father to feel his son gone for years -- because Monique is gone for life."
Fellow demonstrators called out in response: "Amen!" "Yes!"
The uncle, Richard Cartier, was joined by supporters who held signs that said "Justice for Monique!" and "Adult car, adult conviction," and depicted a memorial portrait of her. They expressed anger that the teenage defendant was not prosecuted as an adult.
In an interview with ABC7 on Friday, Los Angeles County District Attorney George Gascón was asked about the decision to not try the 17-year-old as an adult.
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"One of the commitments that I made when I ran for office, and I was very clear, is that we would follow the science and data," Gascon said. "And when it came to juveniles, we will not refer juveniles to adult court.
"The reality is that the human brain is not fully developed until we're in our mid-20s," the DA said. "Frankly, the 18-year-old threshold is an arbitrary legal threshold."
Charges were filed in the case on April 7 after Los Angeles County district attorney's office completed its investigation.
Shortly before the collision, prosecutors claimed in court, the teenager had been "racing" with a female friend and swerving in and out of lanes, the Los Angeles Times reported. The Lamborghini reached a speed of 106 mph when it hit Munoz, nearly splitting her vehicle in two, according to prosecutors.
A defense attorney strongly denied that the defendant had been "racing."
Muñoz, 32, of Hawthorne, was driving home from work shortly after 5 p.m. on Feb. 17 when a black Lamborghini SUV collided with her Lexus sedan, police said. Her car was demolished in the crash.
Los Angeles Fire Department firefighter-paramedics responded to the scene, where Muñoz was pronounced dead, police said.
The 17-year-old driver of the Lamborghini was hospitalized following the crash, police said. He was booked for vehicular manslaughter on Feb. 23, the Los Angeles Police Department said.
Investigators say the teen was driving at a high rate of speed at the time of impact.
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