A veteran Los Angeles Police Department detective from Simi Valley charged with premeditated murder pleaded not guilty Monday to the decadesold slaying of her ex-boyfriend's wife.

Stephanie Lazarus, 49, was arrested last month and charged with the murder of Sherri Rae Rasmussen, whose body was found badly beaten and with multiple gunshot wounds in her Van Nuys condominium on the evening of Feb. 24, 1986.

The 29-year-old Rasmussen was the director of critical care nursing at Glendale Adventist Medical Center.

At the time of Rasmussen's death, Lazarus, who was most recently assigned to the art theft detail, had been a member of the LAPD for just two years.

The Los Angeles County district attorney's office charged Lazarus with capital murder, including a special circumstance allegation of murder during the commission of a burglary, stands to put her on death row. She is also charged with use of a handgun.

Though LAPD investigators knew Lazarus had a long-term romantic relationship with the victim's husband, John Ruetten, before Rasmussen's murder, Lazarus was not an initial suspect.

Detectives instead pursued the theory that Rasmussen was killed when she found two men burglarizing her home.

In February 2009, detectives reexamined Rasmussen's murder as part of a systematic review of cold cases and were able to link Lazarus to the crime using DNA evidence.

During her arraignment July 6, the judge granted Lazarus' request to appoint Mark E. Overland as her new attorney.

In a phone interview with the Simi Valley Acorn Monday evening, Overland said many questions remain in this case and there has already been misinformation in the media.

He said the press has reported that Rasmussen was shot with a .38-caliber revolver, but police reports show that the bullets could have been fired from a .38 or .357 Smith and Wesson.

This detail becomes important because a few weeks after Rasmussen was murdered, Lazarus filed a report with the Santa Monica Police Department that someone had broken into her car and stolen her .38caliber revolver, among other things.

Also in question is the DNA evidence, Overland said.

According to reports, an undercover officer trailed Lazarus before her arrest and obtained a utensil with traces of her saliva. That DNA sample was compared to a sample of saliva taken from a bite mark on Rasmussen's inner left forearm, Overland said.

He said the accuracy of that data, which was stored for 23 years, "remains to be seen."

"DNA requires interpretation of data. And the interpretation, number one, depends on who is doing the interpreting and, number two, it depends on how good the data is," he said. "There's contamination, there's deterioration, there's any number of things that could happen to (the sample)."

In addition, the sample taken from the scene of the crime contains the DNA of more than one person, Overland said.

When asked about the motive that's been provided by detectives, which paints Lazarus as a scorned lover out for revenge, Overland said it "seems a little peculiar" that whoever killed Rasmussen knew that she had called in sick to work that day.

He added that claims by Rasmussen's parents that they told police an ex-girlfriend who was an LAPD officer had threatened their daughter are unsubstantiated.

"There's no evidence of that other than their statements, and their statements are based on whatever Sherri told them," he said. "They say they also told police this back in 1986, and the police deny that was ever mentioned to them back in 1986. So someone is not recollecting properly."

The LAPD has already come under fire for not considering Lazarus a suspect during the original investigation.

"You have a prosecutor that is saying don't trust anything we've done 23 years ago but trust us now," Overland said.

The district attorney's office said the two prosecutors on the case would not speak to the media.

Lazarus' next day in court is July 21. She is being held without bail at Century Regional Detention Facility in Lynwood.