Marin investigators link 1973 murder to Idaho man

Investigators have arrested an Idaho resident on suspicion of murdering a San Rafael woman in 1973, the Marin County Sheriff's Office announced Thursday.

Michael Eugene Mullen, 75, was linked through DNA evidence to the case of Nina Fischer, who was murdered in her Point San Pedro Road home. Fischer was 31 years old.

Authorities took Mullen to the Lemhi County Jail in Idaho, where he awaits trial for extradition to California.

The victim's husband, Gunnar Fischer, found her body when he returned home from his office in San Francisco that evening, authorities reported at the time. She had been bound, gagged and shot twice.

Investigators found no signs of forced entry into the house. The Fischers' two-year-old daughter was found unharmed and sleeping in another room.

The Fischers were Swedish citizens who had been living in the Bay Area for three years. They were planning to move into an apartment in San Francisco.

Gunnar was an executive at Corona Industries International Corp. On the day his wife was found dead, he tried several times to call her.

Neighbors last saw Fischer in her yard, where she was talking to a moving crew that was delivering a shipping container for her.

“The case was investigated but unfortunately ultimately stalled due to a lack of investigative leads,” the sheriff's office said Thursday.

In 2021, Marin County Sheriff's detectives turned the case over to the state Department of Justice's Family Tracing Program to help search for clues. Within months, they received a tip from state authorities, reopening the investigation.

Investigators used DNA evidence collected at the crime scene, said Sergeant Adam Schermerhorn. He said investigators were not aware of any previous connection between Mullen and the victim.

The sheriff's office thanked the Idaho State Police, Lemhi County Sheriff's Office, Marin County District Attorney's Office, California Department of Justice and the FBI for their assistance in this case.