That suspect was released from the hospital Thursday and taken straight to the Santa Clara County Jail.
He was arraigned Friday on two counts of murder.
District Attorney Jeff Rosen revealed new details about what happened in the moments before Rebecca Olsen, 46, and her 14-year-old son, Charles "Charlie" Olsen were killed.
During the court hearing, Duncan McQuarrie, 39, though present, did not fully enter the courtroom, staying at the doorway between the courtroom and inmate holding in a yellow shirt and appearing to be in a wheelchair. According to the California Highway Patrol, McQuarrie sustained minor injuries in the Aug. 26 crash, which claimed the lives of the mother and son.
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"To imagine the senselessness of this crime, the recklessness of it, and the tremendously horrible impact that it's had on this family is, I think, what's moved many of us about this particular case," Rosen said.
The DA's office revealed that McQuarrie had driven for nine miles on the wrong side of Highway 85, speeding at 100 miles per hour before the fatal collision.
Deputy District Attorney Michael Gadeberg provided further details, stating, "At one point, the defendant stopped his car and got out and walked around in the middle of traffic. He then got back into his vehicle and continued to drive the wrong way until ultimately striking and killing a mother and child."
McQuarrie, a Florida resident, had been in California for less than a week visiting family. He was driving a rented Toyota at the time of the crash. According to CHP, McQuarrie was under the influence, with open alcohol containers found in the vehicle, and he exhibited confused behavior.
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The CHP officer also reported on McQuarrie's prior criminal record, including two DUI arrests in Florida in 2013 and 2021, along with convictions for drug possession in 2021 and 2022.
"We've charged the defendant with murder because of the reckless disregard for human life that he showed in driving 100 miles an hour for several minutes across several miles in the middle of the day," Rosen said
The victims' loved ones were not present in court, but Charlie Olsen's father had shared a statement on Reddit last month, calling his son "my best friend, travel buddy, and the only person I ever truly felt at home with."
Rosen read more from the father's statement after the arraignment: "If you're a parent, give your kids that extra hug today for me."
McQuarrie is being held without bail. His next court date is scheduled for Nov. 7.