Marissa DiNapoli, 18, was reported missing in Morgan Hill, California, on June 30, 2025. Her body was found two days later, and her boyfriend was later charged with her murder.
On the night of Saturday, June 28, 2025, DiNapoli sent her parents a text message at around 9:15 p.m. She told them she was staying at a friend’s house that night and would be home by 8 the next morning.
The next morning, home surveillance cameras recorded DiNapoli and her boyfriend, 20-year-old Martin Mendoza Jr., leaving a house on Trail Drive, just outside Morgan Hill’s city limits, at around 9:45 a.m. Mendoza was renting the home at the time.
The footage showed the two of them arguing as they walked down a staircase. According to court documents, Mendoza was confronting DiNapoli about contacting her ex-boyfriend, and her expression in the video was visibly apprehensive.
DiNapoli’s car was later found parked in the same area near the house. Investigators said the footage, including the argument it captured, became an important piece of evidence early in the case.
Later that day, DiNapoli did not show up for her scheduled shift at a local Starbucks, where she worked as a barista. Missing work without notice was out of character for her.
Friends said that DiNapoli and Mendoza had an on-and-off relationship that had lasted about two years, and that the two had resumed contact as friends earlier that spring, in May.
One friend, Jaslyn Gutierrez, later told reporters that DiNapoli had confided in her about her fear of Mendoza, saying DiNapoli told her “he would kill her, that he would not stop.”
Gutierrez said she and DiNapoli had graduated from Opportunity Youth Academy together just three weeks earlier and had been friends since their freshman year of high school.
On Monday, June 30, DiNapoli’s family reported her missing to the Morgan Hill Police Department. That evening, officers responded to a disturbance call on Trail Drive involving several men knocking on a door.
Across the street, officers spoke with a family member of DiNapoli, who told them she was searching for Mendoza to confront him about DiNapoli’s whereabouts.
During this encounter, officers saw Mendoza retreat into the home to avoid speaking with them. He was not arrested or held for questioning that night, and he left the area sometime afterward.
In the days that followed, the Morgan Hill Police Department expanded its investigation, working with more than 30 investigators from 15 agencies, including the Santa Clara County District Attorney’s Office, the Santa Clara County Sheriff’s Office, the FBI, and the U.S. Department of Homeland Security.
Police publicly identified Mendoza as a person of interest and asked the community for help locating both him and DiNapoli. To raise awareness, DiNapoli’s sister posted the surveillance footage from Mendoza’s home on social media, asking the public for tips.
Police also released a public appeal asking anyone with information to come forward, and they described Mendoza as believed to be driving a white Toyota Camry.
The FBI’s San Francisco field office shared the appeal on social media, asking the public for tips and directing them to Morgan Hill Detective Kyle Tolentino, who was leading the investigation.
On July 1, traffic cameras recorded Mendoza driving his car across the U.S.-Mexico border at the San Ysidro crossing. He had his cell phone with him at the time.
On the morning of Wednesday, July 2, DiNapoli’s friends and community members gathered at Uvas Reservoir to search for her, since many of them knew it was a place she and Mendoza used to visit together.
That evening, the search shifted to Anderson Lake County Park. At around 7:30 p.m., a community member flying a drone spotted what appeared to be human remains along Dunne Avenue on the east side of the lake and alerted authorities.
The Santa Clara County Sheriff’s Office confirmed that a body had been found, though it had not yet been formally identified.
The next day, Thursday, July 3, the Santa Clara County Coroner’s Office confirmed that the remains belonged to DiNapoli. Morgan Hill Police Captain Mario Rodriguez told reporters, “We can confirm the body that was located on east Anderson Lake is, in fact, Marissa.”
Police also released a statement describing her as “a vibrant member of our Morgan Hill community.” Her family asked that no fundraising accounts be created in her name, explaining that they were not seeking financial donations and instead asked for privacy as they grieved.
That evening, friends, family, and community members gathered near Anderson Lake for a vigil in her memory. Her former teacher, Tara Guerrero, brought candles and flowers that her students had collected for the gathering.
In the days after the discovery, police said they repeatedly tried to reach Mendoza through his cell phone and through his family, but he did not respond to any of their attempts. He still had not been located, and he remained the investigation’s main person of interest.
On July 6, Mendoza attempted to walk back into the United States on foot at the Calexico border crossing, without his car or his cell phone. U.S. Marshals arrested him there and took him to the Imperial County Jail in El Centro.
The Imperial County Sheriff’s Office released his booking photo, and within 48 hours he was transported from the jail near the border to Santa Clara County to face charges. A Morgan Hill police captain said that once the arrest warrant was secured, “we would be ready to apprehend Mr. Mendoza.”
Morgan Hill Mayor Mark Turner also released a statement following the arrest, saying the capture “does not bring Marissa back, it is a crucial step toward justice.”
On July 8, Mendoza appeared in Santa Clara County court for his arraignment. He was charged with first-degree murder and the use of a knife to commit the murder. Superior Court Judge Franklin E. Bondonno denied him bail and ordered the release of additional case details to the public.
He remained out of view of DiNapoli’s family and friends during the hearing, staying behind his defense attorney and never stepping fully into the courtroom to enter a plea.
Prosecutors said that Mendoza and DiNapoli had traveled together toward Anderson Lake that morning based on cell phone data, and that he stabbed her five times in the back near a picnic area known as Woodchoppers Flat before leaving her there.
District Attorney Jeff Rosen called it “a lethal and brutal attack.” He also told reporters that Mendoza faced 26 years to life in prison if convicted of first-degree murder, and 16 years to life if convicted of second-degree murder, and he credited investigators, saying, “The Morgan Hill Police Department did an excellent job in this investigation.”
A follow-up hearing was scheduled for September 9.
Outside the courthouse, DiNapoli’s family and friends spoke with reporters. Her sister, Monice Ramirez, said the hearing had left them without answers, telling reporters, “We didn’t get any answers.”
She also said the family was grateful for the public support they had received, adding, “We are really honored to have all of this support and the attention.” During a news conference outside the courthouse, Ramirez held a poster with DiNapoli’s photograph near the county jail, where Mendoza was also being held.
Inmates in an adjacent exercise yard, curious about the gathered reporters, began asking questions, and once Ramirez called out Mendoza’s name, several of them shouted, “Justice for Marissa!”
Court records unsealed around the time of the arraignment revealed that Mendoza had a documented history of domestic violence, including a restraining order granted to another woman against him in 2022.
Rosen declined to comment directly on Mendoza’s prior criminal record during the news conference, but he said evidence about the couple’s relationship, including earlier reports of abuse, would be part of the case moving forward.
In the weeks that followed, DiNapoli’s family and community members raised concerns about how the Morgan Hill Police Department had handled the case, specifically its decision not to detain Mendoza during the June 30 encounter, despite being told he was the last person seen with DiNapoli.
The family started an online petition on the platform Change.org, addressed to the City of Morgan Hill, Santa Clara County officials, and the California Department of Justice, calling for an independent investigation and a formal audit of the department’s response.
In a public statement accompanying the petition, the family laid out a timeline of complaints: that DiNapoli’s sister gave officers Mendoza’s exact location the day after DiNapoli was reported missing; that officers confronted Mendoza in person but did not arrest or detain him for questioning.
That he left the area within hours of that encounter; that a community member, rather than police, ultimately found DiNapoli’s body; and that Mendoza was only caught by chance when he tried to cross back into the United States a week after her death.
The family also said they believed racial and systemic bias played a role in the delayed response, though police did not directly address that specific claim in their own public statements.
Within days, thousands of people had signed the petition, with the total later surpassing 8,500 signatures. In response, the Morgan Hill police chief said the department was not seeking to judge how the family was grieving and acknowledged that some of their anger was directed at the department.
The department maintained that it did not have sufficient evidence at the time of the June 30 encounter to arrest Mendoza.
Around the same time, the Morgan Hill community organized several events to support one another, including grief counseling for students, healing circles at a local community center, and a domestic violence awareness night titled “Awareness and Education.”
The event featured a counselor who spoke about recognizing early signs of abuse, and the nonprofit organization Community Solutions set up a resource booth for survivors.
Mendoza’s case continued through the rest of 2025. His plea hearing, originally scheduled for September 9, was later postponed.
By early December 2025, his arraignment had been pushed back a second time, to February 2026, after his defense attorneys requested a continuance, saying they needed additional time to review the evidence in the case.
DiNapoli’s family and supporters attended the December hearing wearing sweatshirts printed with her photograph. Mendoza, who was 20 years old at the time of the killing, had turned 21 by the time of that hearing.
As of that hearing, he had not entered a plea, and he remained in custody without bail throughout this period. Detective Tolentino continued to ask anyone with information about the case to come forward.
Marissa DiNapoli was born on May 14, 2007, the youngest of eight siblings. She was born to Julian Ramirez Sr. and Anita Ramirez, and she and her siblings spent time in foster care after the family faced significant challenges.
She was later adopted by the DiNapoli family, who gave her a permanent home. She grew up in Morgan Hill, in the South Bay region of the San Francisco Bay Area, the same community where 15-year-old Sierra Lamar disappeared in 2012 while walking to her school bus stop.
A suspect was later arrested in that case, but Lamar’s remains were never recovered. According to her family, all eight siblings were former foster youth who went on to become community leaders, educators, and professionals, earning degrees from universities including UCLA, Stanford, Columbia, and the University of California, Berkeley.
Her siblings, including Julian and Moses Ramirez, later spoke publicly on her behalf, thanking the community members who joined the search for their sister and asking the public to continue supporting the family.
On June 5, 2025, DiNapoli graduated early from Opportunity Youth Academy, an alternative high school in Santa Clara County. She had registered to attend Gavilan College that fall and was working as a barista at a local Starbucks in the meantime.
Her former teacher, Tara Guerrero, remembered her as someone who “had the brightest smile that would light up every room.” Guerrero also said DiNapoli often did kind things for people in the community, including bringing food to unhoused people who lived near the school.
Guerrero had joined the family’s search efforts in the days before DiNapoli’s body was found. Friends and classmates described her as caring, ambitious, resilient, and consistently kind to those around her, and her close friend Jaslyn Gutierrez said the two had been inseparable since their freshman year of high school.
Her sister, Monice, remembered her, saying, “Marissa, she was loved.”
