San Francisco Woman Found Guilty of Murder

A San Francisco jury has convicted 55-year-old Lisa Gonzales of second-degree murder for the 2018 killing and dismemberment of her roommate, Margaret Mamer. The verdict was announced on April 2, 2026, bringing a conclusion to a disturbing case that shocked the city.

Details of the Gruesome Crime

District Attorney Brooke Jenkins, who previously worked on the case as a homicide prosecutor, described the crime as “one of the most gruesome our city has experienced in recent history.” Jenkins recounted the difficulty of the initial investigation and the harrowing testimony presented during grand jury proceedings.

Missing Person Report and Initial Investigation

Margaret Mamer was reported missing on June 1, 2018, after friends expressed concern over escalating tensions between her and Gonzales. The following day, police received a report suggesting a possible murder had occurred at the roommates’ apartment in the 200 block of 14th Street in the Mission District.

Discovery of Remains

Upon arriving at the apartment, Gonzales told officers that Mamer had moved to Eureka weeks prior. However, a search of the building’s storage area revealed a blue plastic container containing human remains, later identified as those of Margaret Mamer.

Evidence and Testimony

A third roommate testified to hearing sawing noises from the bathroom for hours and detecting strong odors of vinegar and bleach. She also reported a missing blue storage container and a hacksaw found under the sink. When questioned about Mamer’s whereabouts, Gonzales stated she had left “but not the way she wanted to.”

Gonzales' Motive

Coworkers testified that Gonzales had repeatedly expressed her desire for Mamer to leave the apartment. When presented with legal eviction options, Gonzales allegedly responded, “No thanks. I’ll do it my way.”

Autopsy Findings and Prosecution

An autopsy revealed that Mamer died from multiple sharp-force injuries to her head, face, skull, and chest. Prosecutors argued that Gonzales dismembered the body to conceal the murder, leaving the remains in the storage unit for several weeks before their discovery.

Sentencing and Challenges

“Sadly, not only was she dismembered, but it took a number of weeks to locate her. And so, the body had experienced significant decay by then,” Jenkins stated. She also noted the challenges in pursuing a first-degree murder charge due to the inability of the victim to testify.

Gonzales remains in custody and faces a sentence of 16 years to life in prison. A sentencing date will be scheduled at a hearing later this month.