Former LAPD detective who murdered ex-lover’s wife and hid his crimes for decades remains behind bars

LOS ANGELES– The former Los Angeles police detective, convicted in 2012 of murdering her ex-lover’s wife, was denied parole Wednesday for the 1986 murder and will continue serving her 27-year sentence life imprisonment.

Stephanie Lazarus was convicted of murdering Sherri Rasmussen, a 29-year-old hospital intensive care nursing director, who was shot three times in the home she shared with her husband, John Ruetten.

Lazarus was sentenced to 27 years to life in prison after a jury found her guilty of first-degree murder. She became eligible for parole in 2023 after the state of California passed a law giving special consideration to juvenile offenders who committed their crimes when they were under 26 years old.

Lazarus was 25 years old at the time of the murder.

Commissioner Garland said the board had “found good reason to revoke Lazarus’ parole” and would reconvene for further hearings regarding Lazarus.

There will be another chance to get parole. Lazarus will be summoned for another fitness hearing within 120 days.

“The Killer Down the Hall,” a new “20/20” airing Friday, Oct. 4 on ABC at 9 p.m. ET and streaming the next day on Hulu, features the story of Stephanie Lazarus, including interviews with the family of the victim and friends.

“It’s without a doubt, pound for pound, one of the greatest true crime stories of all time,” Mark Groubert, a journalist who wrote an article about the unit, told “20/20.” LAPD by Lazarus for LA Weekly.

Ruetten and Lazarus met at UCLA in the 1970s and had a friendly relationship involving casual sex, according to Ruetten’s testimony at Lazarus’ trial. Ruetten also testified that he never considered Lazarus his girlfriend. He also admitted to sleeping with Lazarus shortly after becoming engaged to Rasmussen. On February 24, 1986, Ruetten discovered his wife lying in a pool of blood on the living room floor of their apartment in Van Nuys, California. He immediately called 911.

Initial investigators determined that the crime scene in the home Ruetten and Rasmussen shared had all the signs of a “hot chase,” a term police use to describe a home invasion. Investigators strongly believed that Rasmussen was the victim of a burglary that escalated into his murder. She had ligature marks on her wrist, indicating that at some point someone had tied her up. She also had three gunshot wounds to her chest and a bite mark on her arm.

The night of the murder, LAPD homicide detective Lyle Mayer questioned an emotional John Ruetten about what he knew about the day Sherri was killed.

Ruetten denied killing his wife and agreed to submit to a polygraph examination, but the results were inconclusive. However, according to the Rasmussen family lawyer, he had a rock-solid alibi.

RELATED: Parole denied to former LAPD detective convicted of murdering ex-boyfriend’s wife

“He was at work that day,” said John Taylor, the attorney. “He had left work. He stopped to get his dry cleaning, then he returned between 6 p.m. and 7 p.m. and found his wife murdered in the living room of the house.”

In the eyes of Mayer, the lead detective, Ruetten was a grieving husband. Investigators said they didn’t feel like he was hiding anything and that as far as they were concerned, he wasn’t a suspect — and they told him that.

“I believe your house was broken into today,” Mayer told Ruetten in the interrogation room. “Once these people, or this person, or whoever, were inside, I believe they were trying to steal your stereo and probably other items.”

Shortly after Rasmussen’s murder, investigators quickly explored a new lead. Another burglary with a similar modus operandi took place in the same area of ​​Van Nuys.

A woman interrupted the burglary when she returned home and found two men in her house, one of whom was armed. They fled and sketches of the suspects were made. Even though the LAPD had these new suspects, there was no evidence directly linking anyone to Rasmussen’s murder. Sherri’s family and friends believed the motive was personal. Her father, Nels Rasmussen, says he urged police to investigate a disgruntled nurse Sherri had worked with, as well as Ruetten’s former lover, Stephanie Lazarus, whose name Rasmussen never knew. But detectives continued to focus solely on the burglary theory.

At this point, detectives said they have no witnesses, fingerprints or murder weapons.

The case remained unsolved until 2001, when the Los Angeles Police Department launched the LAPD’s Cold Case Unit. That year, detectives learned of more than 9,000 unsolved murders spanning more than two decades, and Rasmussen’s case was one of them.

Using new technology and fresh eyes, cold case investigators re-examined the bite mark that was on Rasmussen’s forearm.

Detective Cliff Shepard was the lead officer who investigated the Rasmussen case on behalf of the unit.

“Up until that point, no one other than Mayer and myself had really looked at it,” Shepard said. “When I re-read the reports, they indicated that a bite sample was taken,” Shepard said. “And when I looked at the evidence…no evidence of a bite mark swab. So I checked with our property, they verified that they didn’t book the swab in our evidence room. There’s no record of that.”

Shepard enlisted the help of Jennifer Francis, a criminologist with the LAPD’s Scientific Investigations Division, to locate the swab, which she traced to a freezer at the Los Angeles County medical examiner’s office.

The swab was sent to forensics for analysis, which yielded the DNA profile of an unidentified woman, but yielded no matches in law enforcement databases.

DNA had given police a profile, but they did not provide a name. Even with this new information, the investigator’s theory remained that Sherri’s killer(s) were burglars. In 2005, Shepard left the investigation into the Rasmussen case without identifying a suspect, even with the DNA profile.

“My biggest regret is not interviewing Ruetten. Not meeting him and having a face-to-face,” Shepard said.

The case remained unsolved until 2009, when Detective Jim Nuttall of the Van Nuys Division took over the investigation with fresh eyes.

One of the first things Nuttall noticed was Francis’ four-year-old DNA report indicating a woman was present during the murder. He also thought the stereo equipment stacked near the door was suspicious, leading him to question the burglary theory.

After returning to speak with Sherri and Ruetten’s family, Nutall and his team of investigators compiled a list of five female suspects who were in Rasmussen’s orbit. Three of the five people were immediately eliminated – Rasmussen’s sister, mother and a close friend – after submitting DNA samples. The fourth suspect, a nurse who allegedly had tensions with Rasmussen at work, was also eliminated.

The fifth suspect was Stephanie Lazarus, Ruetten’s ex-college lover. Rutten told Detective Nuttall that he had already given Lazarus’ name to the LAPD 23 years ago. The conversation, however, was never documented.

Four months after reopening the Rasmussen case, Nuttall did something no other officer investigating Sherri’s murder had done: He took a hard look at Lazarus.

The decision was made to have Lazarus followed by a special surveillance unit to observe him and obtain a DNA sample. After following her, the unit noticed that she had thrown a cup into a public trash can. They collected the cut to test the DNA against that of the bite mark.

The DNA matched Rasmussen’s bite mark, providing detectives with the evidence they needed to arrest Lazarus. Lazarus was charged with Sherri’s murder and pleaded not guilty.

In February 2012, 26 years after Rasmussen’s murder, Lazarus stood trial in a downtown Los Angeles courthouse. She was convicted of first-degree murder and sentenced to 25 years to life in prison and an additional two years for the firearm charge.

After her conviction, Lazarus continued to profess her innocence, but changed her story in 2023 when she became eligible for parole.

“The only reason she confessed is because she wants to get parole,” said Teresa Marie Lane, a sister of Rasmussen. “We really have to keep her because she has no respect for what she did. She has no remorse.”