It was a February morning in 1986. Sherri Rasmussen, a 24-year-old nursing director with a bright future, was found dead on the floor of her Van Nuys condo. She’d been beaten. She’d been bitten. She’d been shot three times. For twenty-three years, the official story was that two unidentified Latino men had broken in, botched a robbery, and killed her. But that was a lie.
The truth is much more chilling. Who killed Sherri Rasmussen? It wasn’t a random burglar. It was Stephanie Lazarus, a decorated Los Angeles Police Department detective who had been obsessed with Sherri’s husband.
Lazarus didn't just kill Sherri; she sat in the same buildings as the investigators who "couldn't" solve the case. She rose through the ranks. She became a specialist in art theft. She lived a full, successful life while Sherri’s blood dried on a cold case file. This wasn't just a murder; it was a systemic failure of the LAPD to look at one of their own.
The Crime Scene That Didn't Make Sense
When Sherri’s husband, John Ruetten, came home on February 24, 1986, he found their BMW in the driveway with the engine off but the door open. Inside, the house was a mess. Sherri was dead.
The lead investigator at the time, Lyle Mayer, went all-in on the "burglary gone wrong" theory. It seemed plausible if you didn't look too hard. A silver bowl was missing. Some electronics were stacked up. But things were weird. Really weird. Why would a burglar stop to engage in a knock-down, drag-out fight with a woman when they could just run? Why was there a bite mark on her arm? And why was there a "contact" gunshot wound through a quilted blanket, used as a makeshift silencer?
Sherri’s father, Nels Rasmussen, knew something was off. He told the police, repeatedly, that John’s ex-girlfriend—a cop named Stephanie—had been harassing Sherri. He told them about the time Stephanie showed up at Sherri’s workplace in her uniform to tell her, "If I can't have John, nobody can."
The LAPD ignored him. They actually got annoyed with him. They wrote him off as a grieving father who had watched too many detective shows. They didn't want to believe a sister in blue could be a killer.
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The DNA "Smoking Gun" and the 2009 Breakthrough
Fast forward to 2004. DNA technology had changed the game. A criminalist named Jennifer Francis looked at the swab taken from that bite mark on Sherri’s arm. The original detectives thought it was from a man. They were wrong. The DNA belonged to a woman.
Even then, the case stalled. It took another five years for the case to land on the desks of Jim Nuttall and Pete Barba. They were looking at cold cases and realized the "burglary" theory was total nonsense. Nothing of actual value was taken. The stack of electronics was just a stage set. This was personal.
They started looking at the women in John Ruetten’s life. When they saw the name Stephanie Lazarus and realized she was a current LAPD detective, the room went quiet.
They had to be careful. You can't just accuse a veteran detective of murder without ironclad proof. They followed her to a Costco. They watched her eat. When she threw away a soda cup, they grabbed it. That saliva contained the DNA they needed. It was a perfect match for the bite mark on Sherri’s arm.
The Interrogation: A Masterclass in Denial
If you haven't seen the video of Stephanie Lazarus being interrogated, you need to. It’s haunting. Her colleagues brought her into a room under the guise of needing help on an art theft case. She’s relaxed. She’s "one of the guys."
Then, they pivot. They start asking about John Ruetten.
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You can see the exact moment her "cop brain" realizes she’s the suspect. She starts playing dumb. "John? Oh, yeah, I remember a John. We dated a bit." She uses classic distancing language. She fidgets. She tries to leave.
But the detectives, led by Greg Stearns, didn't let up. They knew they had her. The woman who had spent years solving crimes was now the one being dismantled by the very techniques she likely used on others.
Why Did It Take So Long?
The question of who killed Sherri Rasmussen was answered in 2012 when Lazarus was convicted, but the "why" of the delay still burns.
The LAPD faced massive criticism for "Blue Wall of Silence" behavior. Whether it was intentional protection or just gross negligence, the fact remains that a killer was hiding in plain sight for two decades. The original investigators didn't even mention Lazarus in the formal "murder book" for the first few years, despite Nels Rasmussen's constant pleas.
The trial was a media circus. John Ruetten had to testify about his "friends with benefits" relationship with Lazarus that continued even after he got engaged to Sherri—a fact that likely fueled Lazarus’s rage. It was a messy, tragic triangle that ended in a brutal execution.
Lessons from the Rasmussen Case
This story isn't just true crime fodder. It's a reminder of how bias can blind justice. Because the police were looking for "thugs," they ignored the detective in the next cubicle.
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How to Track Cold Cases
If you are interested in how cases like this finally get solved, look into these specific areas of forensic advancement:
- Forensic Odontology: While bite-mark analysis is often criticized today as "junk science," in this case, it provided the biological material (saliva) necessary for DNA testing.
- Genetic Genealogy: Though not used in the 2009 arrest, this is how most cold cases are being cracked in 2026.
- Victim Advocacy: The persistence of Nels Rasmussen is the only reason this case stayed alive. If you are dealing with an unsolved matter, documenting every interaction with law enforcement is vital.
Final Facts and Verdict
Stephanie Lazarus was sentenced to 27 years to life. She has been up for parole recently, which has reignited the pain for the Rasmussen family. In 2023, she was actually recommended for parole, but the decision has faced intense scrutiny and pushback from the Los Angeles District Attorney’s office.
The legacy of Sherri Rasmussen is one of a life stolen by obsession and a justice system that, for a long time, preferred a comfortable lie over a difficult truth.
Take Action:
- Support Cold Case Units: Many police departments are underfunded in their cold case divisions. Support local initiatives that prioritize DNA testing for backlogged cases.
- Document Harassment: The Rasmussen case proves that "minor" harassment can escalate. Always keep a digital and physical trail of stalking or threats.
- Read the Transcripts: For those interested in the psychology of the "criminal mind" within law enforcement, the trial transcripts of People v. Lazarus offer a rare look at how a professional investigator tries—and fails—to outmaneuver the law.
The case is officially closed, but the conversation about police accountability and the "Blue Wall" continues.