Autopsy released for Margaret Mamer, dismemberment homicide victim

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Warning: Grisly details follow.

The San Francisco Medical Examiner’s office on Monday released an autopsy report for Margaret Mamer, whose dismembered body was last year discovered in a storage room at 255 14th St., where she had been renting a room. 

Police arrested Mamer’s roommate, Lisa R. Gonzales, on suspicion of homicide. She is charged with murder, to which she has pleaded not guilty. She has been held without bail for more than a year now and is next scheduled to appear in court on September 24. 

The 72-page report contains initial examinations and notations by medical examiners during Mamer’s autopsy. It states that the victim suffered multiple traumatic injuries; Mamer received several “sharp force” injuries to the head and neck, totaling at least seven injuries to the skull and five injuries to the right side of her face. According to the medical examiner, there were also “chop-like” blunt force injuries to the side of the neck and head. 

The coroners found that the victim was additionally stabbed in the chest with a sharp object, and noted that the victim also had injuries on her fingers.

After her death, the medical examiner reported that Mamer’s remains were sawed apart. They found that portions of the left and right forearms and legs had been sawed off with a thin, handsaw-like tool and highlighted that there had been several “false starts.” The report details that the victim had been sawed in half; the medical examiners pointed to cut marks along the vertebrae where the victim had her abdomen cut into two pieces, separating the spine from the pelvis bones. 

Mamer had been reported missing in May of last year, but police only made the grisly discovery at 255 14th Street on June 2, 2018 after a man walked into Ingleside police station and reported a possible homicide. The man said his girlfriend had told him that her mother “murdered someone, cut the body and was attempting to dispose of it.” 

“The reporting male indicated that his girlfriend told him she heard chopping noises, smelled blood and was told by her mother to stay away from the bathroom,” the subsequent police report said.

Once police arrived at the building, they spoke to Gonzales and inspected the apartment. They found that the room Mamer had been occupying had been cleared out. They then took the search downstairs and, as they inspected the storage units in the basement levels belonging to the suspect, discovered bins with bags containing human remains. Police reported that some of the remains were in such bad level of decomposition that maggots had begun to grow and the remains had fluid oozing out of them.

Police obtained a search warrant  during the evening of June 2 and continued to inspect the property. The medical examiner was called in at around 1:30 a.m. on June 3, and no further examinations were done in the basement in order to preserve the remains.

When police arrested Gonzales on June 2 of last year, she told them she didn’t have a “real recollection” of what happened, but that on May 15 she and Mamer had gotten into an argument when Mamer refused to move out. Gonzales told police she thought she may have “flipped.” When asked what she may have done, her response to police was “probably nothing good.”

Because the remains were badly decomposed, the Medical Examiner’s office sent them to Chico State University’s Human Identification Laboratory. Anthropologists there received the remains on July 12 and spent the next five and a half months examining them. In their report, they highlighted parts of the bones marked by saw blades.

It is unclear exactly when Mamer was killed, but earlier reports indicated that she could have died sometime in mid-May and been left to decompose for weeks in the basement.

Calls to both the District Attorney’s office and the Office of the Public Defender were not immediately returned.