San Francisco woman convicted in hacksaw killing of roommate, hid body in storage bin

SAN FRANCISCO - A San Francisco woman was convicted Wednesday of murdering and dismembering her roommate with a hacksaw in 2018, then hiding the remains in a plastic storage bin in a basement after telling the victim she had to move out.

A jury found Lisa Gonzales, 55, guilty of second-degree murder in the death of Margaret Mamer at their shared Mission District apartment.

A sentencing date has not been set.

"The jury’s verdict delivers justice to the victim’s family and friends who continue to grieve and are still deeply impacted by this heinous murder," District Attorney Brooke Jenkins said.

Victim reported missing

What we know:

On June 1, 2018, Mamer was reported missing by friends who had not heard from her for several days and were concerned due to escalating tensions between her and Gonzales, prosecutors said.

The following day, another person told police that a murder may have occurred at a residence in the 200 block of 14th Street. The tipster said Gonzales had killed someone, dismembered the body, and hid the remains in a container in the basement.

Police investigation

Dig deeper:

When officers responded, Gonzales invited them inside. While speaking in the kitchen, she told police she lived in the apartment with one roommate, not Mamer.

She claimed Mamer had previously lived there but had recently moved to Eureka, which prosecutors said was a lie. Gonzales also told officers she helped Mamer move out on May 15, 2018, and had not seen her since.

Officers later searched the building’s garage and found a blue container holding human remains, which were later identified as Mamer.

Roommate’s account

What they're saying:

A third roommate told police that in mid-April 2018, Gonzales gave Mamer a 30-day notice to move out.

On May 15, when the roommate returned home during a lunch break, Gonzales told her not to go into the bathroom, prosecutors said.

Later that day, the roommate noticed a metallic smell throughout the apartment and heard sawing noises coming from the bathroom for about four hours. The next morning, Gonzales was still inside.

When the roommate returned home that evening, she found the bathroom door open and the apartment smelling of vinegar and bleach.

She also noticed a blue container that had held her dirty clothes was missing and saw a hacksaw under the sink in the laundry room. When she asked where Mamer had gone, Gonzales replied that she had left, "but not the way she wanted to."

Cause of death and evidence

Blood spatter from Mamer was found throughout the apartment. An autopsy determined she died from multiple sharp-force injuries to the head and heart, including wounds to her face and skull, as well as a stab wound to the chest.

Prosecutors said Gonzales dismembered the body to conceal the killing. Mamer’s remains stayed in the blue container in the building’s storage area until June 2, 2018, when officers responded to the scene.

Prior statements

Before the killing, Gonzales complained to coworkers that Mamer refused to move out. When advised of legal eviction options, Gonzales responded, "No thanks, I’ll do it my way."

Gonzales remains in custody.