Colorado man convicted in 1978 San Francisco cold case murder of 15-year-old girl sentenced to life in prison
By Carlos E. Castañeda
A Colorado man convicted in the cold case murder of a teenage girl in San Francisco in 1978 was sentenced to life in prison on Wednesday, with parole eligibilty in seven years, authorities said.
Mark Personette, 80, of Jefferson County was convicted in November 2025 of murdering 15-year-old Marissa Harvey, a New York City resident who was visiting her sister in San Francisco. On March 27, 1978, Harvey went to the city’s Golden Gate Park to ride a horse and never returned to her sister’s house. The San Francisco Police Department said her body was discovered the next day in nearby Sutro Heights Park; she had been strangled and sexually assaulted.
DNA testing in the early 2000s showed a male DNA profile on the victim’s clothing and on a piece of dried gum stuck to her back, according to the San Francisco District Attorney’s Office. However, the case went cold after detectives exhausted all leads. In 2020, the department’s cold case unit reopened the case, and through advanced DNA testing and investigative genealogy, Personette was identified as a potential suspect, the DA’s Office said. While under surveillance, FBI investigators saw him discarding trash in a Walmart parking lot over 15 miles from his Denver home; the trash included only personal hygiene items with his DNA, according to the office.
Additional evidence was obtained in a search of Personette’s home, including 1970s maps of San Francisco and California license plates with a 1979 registration sticker, even though he previously denied having been in San Francisco, the DA’s Office said. The subsequent DNA test confirmed that Personette’s DNA was on the victim’s clothing and the piece of dried gum, according to prosecutors.
During the trial, another victim testified that Personette raped her in a wooded area of New Jersey in 1979 when she was 16 years old.
“After almost 50 years, Mr. Personette is finally being held accountable for his heinous crimes against Marissa and will spend the rest of his life in prison,” said District Attorney Brooke Jenkins on Wednesday in a prepared statement. “While nothing can bring Marissa back to her family, today’s sentence hopefully leaves her family with a sense that justice was done for all that they have endured.”
“Mark Personette has been sentenced, and the long wait for accountability is finally over,” said Assistant District Attorney Katherine Wells in a statement. ”While no sentence can undo the unimaginable loss Marissa’s family has carried for decades, I hope this moment brings them some measure of closure. It was an honor to seek justice for Marissa, and to stand alongside her family, the survivor who bravely testified, and the investigators and prosecution team who never stopped working to uncover the truth.”
