San Francisco, CA – San Francisco District Attorney Brooke Jenkins announced today that her office secured a conviction of Mark Personette (80), after a trial by jury for a 1978 cold case murder. Mr. Personette was convicted of first-degree murder.
“At long last, justice has been delivered, and Mr. Personette is being held accountable for this horrific crime,” said District Attorney Brooke Jenkins. “I would like to thank the survivor and the victim’s family for never losing hope and remaining steadfast in their commitment to seeing justice done. Although nothing we do can bring the victim back, I pray this verdict gives the family a sense of closure and inspires others who are still waiting for justice not to lose hope.”
According to testimony and other evidence presented at trial, on March 27, 1978, the 15-year-old victim Marissa Harvey, who was visiting her sister in San Francisco, went to Golden Gate Park to ride a horse. She never returned to her sister’s house. The following day, her body was discovered in the underbrush of Sutro Heights Park by several surfers who were walking through the area. At the crime scene, investigators found a leaf with the victim’s blood and her earring, showing that she was attacked there. Her cause of death was determined at the scene to be strangulation by ligature. An autopsy revealed numerous injuries consistent with a violent attack and sexual assault.
DNA testing in the early 2000s revealed a male DNA profile on the victim’s sweater and jeans, as well as within a piece of dried gum stuck to her back. In 2021, through investigative genealogy, Mr. Personette was identified as a potential suspect. FBI investigators surveilled Personette, in Denver, Colorado, and observed him discarding trash in a Walmart parking lot over 15 miles from his house. They collected the trash, which included only personal hygiene items with his DNA. A search warrant at Mr. Personette’s house showed that he was separating his personal hygiene items from his other trash. He also had 1970s maps of San Francisco along with a set of California license plates with a 1979 registration sticker, though he denied to investigators that he had been in San Francisco. A confirmatory DNA test showed that Mr. Personette’s DNA profile was on the victim’s sweater and jeans, and the piece of dried gum.
A prior victim of Mr. Personette testified that in 1979, a year and a half after Marissa’s death, he raped her in a wooded area of New Jersey when she was 16 years old.
The case against Mr. Personette was successfully prosecuted by Assistant District Attorneys Heather Trevisan and Katherine Wells, with assistance from District Attorney Investigators Douglass Keeley and Gino Guerrero, paralegals Jessica Diamond, Julio Flores Guzman, and IT support from Noaeh Pinaire. Victim Advocates Maria Reynoso, Janet Pedroza, and Lily Bueno worked closely with the victim’s family through the pendency of this case. Additionally, SFPD support dog Auburn and her handler supported the family. The case was solved thanks to the tireless work of the San Francisco Police Department’s Homicide Cold Case Unit
investigators and the Federal Bureau of Investigation’s Denver surveillance team.
“This case shows that time cannot thwart justice,” said Assistant District Attorney Heather Trevisan. “I have not seen, in 25 years, more people willing to sacrifice their time and personal comfort to do their duty. I am proud to have prosecuted this case alongside a dedicated team who worked tirelessly to ensure justice was done and that we honored the survivor and the victim’s family who put their faith and trust in us.”
“After nearly half a century, this verdict brought long-overdue justice for 15-year-old Marissa Harvey,” said Assistant District Attorney Katherine Wells. “We are deeply grateful to her unwavering family, the courageous survivor who testified about Personette’s assault on her, and SFPD’s tireless efforts through the decades to bring Mark Personette to justice. Thank you to the jury who conscientiously considered the evidence in this harrowing case and proved that time and distance will not shield those who commit heinous acts in San Francisco.”
Mr. Personette is currently in custody. He is facing seven years to life in prison. Sentencing is scheduled for December 17, 2025.
Court Numbers: 22000870
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