After evading capture for more than four decades, a man has been sentenced to prison for the brutal 1978 murder of a teenage girl.
Mark Stanley Personette, 80, received a life sentence on Wednesday for killing 15-year-old Marissa Harvey nearly 50 years ago.
Harvey, who was from New York, had been visiting her older sister in San Francisco. She failed to return from a planned day trip to Golden Gate Park, where she intended to go horseback riding.
Surfers discovered her body the following day at nearby Sutro Heights Park. Prosecutors said she had been sexually assaulted, severely beaten and strangled with a ligature.
Personette was finally arrested for the crime in Denver, Colorado, in December 2021—43 years after Harvey’s murder.
Following the arrest, the San Francisco Police Department said detectives had pursued every available lead during the original investigation using the technology of the time. The case ultimately went cold.
Investigators reopened the case in 2021 after advanced DNA testing and investigative genealogy identified Personette as a suspect, prosecutors said.
Early DNA testing conducted in the 2000s found a male profile on Harvey’s sweater and jeans, along with a piece of dried gum stuck to her back. However, the testing could not link the evidence to a specific person.
Mark Stanley Personette, 80, was sentenced to life in prison on Wednesday for the sexual assault and murder of 15-year-old Marissa Harvey in 1978
Marissa Harvey was Personette’s victim. Investigators used DNA from her clothing and a piece of gum found on her back to identify and convict her killer
Nearly two decades later, police turned to investigative genealogy, a forensic technique that compares DNA results with profiles in public genetic databases.
The method allows investigators to develop a detailed genetic profile and locate a suspect either directly or through relatives. It was first used successfully to capture the Golden State Killer in 2018.
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Using the technique, police identified Personette as a potential suspect in Harvey’s sexual assault and murder.
In 2021, FBI investigators watched Personette discard trash in a Walmart parking lot more than 15 miles from his home.
The items they recovered consisted only of personal hygiene products containing Personette’s DNA. Investigators later determined that he had been keeping hygiene-related waste separate from his other rubbish.
The new DNA samples were compared with evidence recovered from Harvey’s clothing and the gum found on her back, producing a match to the 1978 crime.
That evidence provided sufficient grounds for a warrant, leading to Personette’s arrest and eventual conviction.
Investigators also found a 1970s map of San Francisco and California license plates bearing a 1979 registration sticker at Personette’s home, despite his denial that he had ever visited the city.
Personette was arrested in 2021 and is shown in a 1979 booking photograph
During the trial, another woman testified that Personette raped her in a wooded area of New Jersey in 1979, when she was 16 years old.
At the time of Personette’s arrest, police said they believed he may have had more victims and urged law enforcement agencies across the country to review any unsolved sexual assault-related homicides involving young women.
The murderer’s sentencing was hailed by prosecutors in a statement released by the San Francisco District Attorney’s Office.
‘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.
‘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.’