The last time Christa Piccinotti saw her daughter, they embraced with Carena’s 3-year-old son in their arms as he shouted, “family hug.”
A day later, Carena was gone.
“It gives me peace of mind that the last time I saw her, I gave her a huge two-arm hug,” Piccinotti said.
That embrace, she added, has become one of her most cherished memories.
On Oct. 5, Santa Rosa resident Carena Piccinotti died in a crash investigators initially suspected was connected to road rage on Stony Point Road near Rohnert Park.
But the events that led to her death — and what’s happened since — are far more complicated.
A case in limbo
A year later, a roadside memorial still marks the site of the crash, but the criminal case against the driver accused of causing it has been stalled for months.
Santa Rosa resident Diego Diaz Hernandez, 21, was arrested the day of the crash and later charged with her murder. But the case stalled while doctors evaluated his mental state. Investigators concluded Diaz may have been experiencing a severe mental health crisis, and witnesses described him chasing another driver before the fatal collision. It was one of four crashes tied to Diaz that afternoon, starting on Highway 12 in Santa Rosa and ending on Highway 101 near Petaluma.
In May, a Sonoma County Superior Court Judge Kenneth Gnoss ruled Diaz incompetent to stand trial, finding he could not understand the legal proceedings or rationally assist in his own defense. He was ordered into treatment with California Department of State Hospitals and is currently held at Napa State Hospital.
His attorney, Sean Healy, declined to discuss the facts of the case, saying only: “We do hope he will receive the health and support and treatment he needs.” He comes from a loving family, he added.
Family’s first year without her
The ruling means Diaz’s criminal proceedings are paused indefinitely, leaving Carena’s family in limbo too.
For Christa Piccinotti, who was 17 when she gave birth to her daughter, the loss remains overwhelming, especially as the anniversary of the crash brought the painful reality that she hadn’t seen Carena in a year.
On Aug. 29, the family marked Carena’s birthday for the first time without her. Now, their priority is making sure her 4-year-old son is healthy and well cared for in her absence.
“It’s really foreign to live a life without her,” Piccinotti said. “To lose her is literally losing a part of myself.”
Carena Piccinotti was born in Long Beach and raised in Sonoma County. Her family describes her as adventurous and creative, with a love for food, music, painting, museums and the outdoors. She was proud of her Pomo and Wappo heritage, excelled at making friends and stood up for people when they were bullied.
She also poured her energy into her business, Boujee Face & Body, which offered teeth whitening and gems at a Rincon Valley storefront. She had plans to expand to a second location while also running pop-ups across the region.
“She was the face of her company,” Christa Piccinotti said. “She just came up with an idea and just made it happen. I was so impressed and so inspired. It came so naturally for her.”
Above all, Carena was devoted to her son, Ayden. Even at his young age, he remembers her — often pointing to her belongings and telling others that his mom is in the sky.
As the anniversary of Carena’s death approached, her mother said waves of sadness often overtook her, though she remained resolute in caring for her grandson. Then, without warning, a gesture of love for Carena appeared — offering a rare bright spot in a painful year.
The roadside memorial that once held only flowers and candles now includes her photo, resting on a platform placed by an unknown person and discovered just before Carena’s birthday. Painted in shades of pink and purple, it matches the urn that holds her ashes.
“It was such a miracle piece that popped up out of nowhere and it’s absolutely perfect,” her mother said.
Legal safeguards
Under California law, State Hospitals has up to two years to restore Diaz’s competency. If he is not deemed competent by then, he could be released — a scenario that alarms prosecutors who argue he poses a danger to the public.
To prevent that, Judge Gnoss held a probable cause hearing in July. After hearing witness testimony, he ruled there was enough evidence to support allegations that Diaz caused Carena’s death. The ruling is not a finding of guilt, but it preserves the court’s option to request Diaz be placed under a special legal arrangement if he is later released from State Hospitals.
Known as a “Murphy Conservatorship,” the process allows defendants found incompetent to stand trial — but accused of violent crimes — to remain in a state hospital for one year, with annual renewals possible, if they are deemed a danger to themselves or others.
The conservatorship, created in the 1970s after a Santa Cruz County serial killing case raised alarms about public safety, has been applied to at least four people in Sonoma County over the past decade, prosecutors said.
Statewide, the Department of State Hospitals reported 129 people under Murphy Conservatorship as of July, with another 16 referrals pending. The department also operates 581 beds for regular conservatorship at Metropolitan, Napa and Patton state hospitals, with another 44 expected after an expansion at Metropolitan State Hospital in Los Angeles County this year.
The fatal day
Court testimony this summer laid out the events of Oct. 5, 2024, in detail.
Diaz’s vehicle was involved in a series of four crashes across Sonoma County that afternoon:
- Highway 12 at Stony Point Road
- Stony Point Road at Rohnert Park Expressway
- Highway 116 in Cotati
- Highway 101 near Pepper Road
Carena, her partner Anton Brajkovich and their son were heading to the San Francisco Zoo when their Volkswagen was struck in the second crash.
Brajkovich testified that Diaz rammed their car from behind, then struck it again as he tried to pull over.
“He had intent in his eyes that told me he wasn’t going to stop,” Brajkovich told the court. “As I drove away and fled, he was right on my tail.”
According to CHP Officer Michael McVeigh, Diaz forced the Volkswagen into oncoming traffic, where it was struck by a northbound Mercedes-Benz. Carena, riding in the passenger seat, was killed.
Investigators say Diaz kept driving, hitting another vehicle on Highway 116 and another driver off the road on Highway 101. CHP Officer Christian Sanchez testified he found Diaz shortly after, crying, dirty and speaking to himself “as if he had voices in his head.”
Christa Piccinotti said she hopes Diaz is kept off the streets to prevent anyone else from suffering as her family has. As the anniversary passes, she’s trying to look ahead — to move forward after a year defined by grief and survival.
“In terms of breathing and surviving and raising my grandson, it’s halted my life,” she said.
You can reach Staff Writer Colin Atagi at colin.atagi@pressdemocrat.com.
Sonoma County cases that resulted in Murphy Conservatorship
A Murphy Conservatorship is a rare California legal safeguard that allows people accused of violent crimes — but found mentally incompetent to stand trial — to remain in a state hospital if deemed dangerous. It lasts one year and can be renewed annually. Without it, they could be released once the legal time limit for treatment runs out.
In Sonoma County, at least four defendants have been placed under the program since 2017:
- Robert Holladay — Charged May 9, 2017, with murder. Accused of attacking Stephanie Janelle Ashton with a hammer in Santa Rosa; she died months later from her injuries.
- Vanessa Bardella — Charged Aug. 24, 2020, with murder. Accused of fatally shooting Cynthia Janssen near Brookhaven Park in Sebastopol.
- Harvey McCarty — Charged June 17, 2022, with murder. Accused of fatally stabbing David Cummings on Santa Rosa Avenue in Santa Rosa
- Victor Ramirez-Plascencia — Charged Aug. 12, 2022, with murder. Accused of fatally stabbing Enrique Goldbaum at Sebastopol Road and West Avenue in southwest Santa Rosa.