Marin detectives arrest Idaho man in connection with unsolved 1973 case: Police

SAN RAFAEL, CALIFORNIA — Investigators in Marin County are citing the fact that better DNA technology has helped detectives identify a suspect in a cold case that went unsolved for 50 years.

According to the sheriff's office, Nina “Nadine” Fischer was sexually assaulted and killed in her home in the unincorporated community of San Rafael in November 1973 while her husband was at work. Detectives opened a murder investigation, but the trail went cold because there were no leads.

The sheriff's office sent case materials to the California Family Tracing Program in 2021 in hopes of developing new leads, which led to a case resolution a few months later. In the years that followed, investigators conducted an extensive investigation that led them to Michael Eugene Mullen, 75, of Idaho, according to the sheriff.

Members of the sheriff's office and district attorney's office joined the Lemhi County Sheriff's Office and Idaho State Police on Wednesday to arrest Mullen on suspicion of murder.

“The Marin County Sheriff's Office would like to thank the Idaho State Police, Lemhi County Sheriff's Office, Marin County District Attorney's Office, California Department of Justice and Federal Bureau of Investigation for the countless investigative hours and perseverance that helped bring this case to a close,” the sheriff's office wrote on Facebook.

Mullen was taken to a prison in Idaho and is awaiting extradition to California.