"These are folks, one side of the hallway investigating a member of the other," Beck said at a news conference. "And it is very difficult."
On June 5, detectives lured Lazarus to a jail cell in the building, telling her there was a suspect in an art theft case they wanted her to question. She walked down to the basement, removed her weapon, and went into the cell, not knowing it was a trap.
The detectives then told her they wanted to talk about the Rasmussen case. At some point Lazarus asked for an attorney and halted the conversation.
When Lazarus appeared in court to face murder charges, Rasmussen's parents watched in stunned silence. The woman they suspected almost a quarter of a century ago was finally being charged with their daughter's murder.
Rasmussen's parents told police after the murder that Sherri had been worried that someone was following her and that her husband's ex-girlfriend, who was a police officer, had accosted her on a couple of occasions.
"They told the police that the ex-girlfriend had gone to Sherri's workplace and confronted her, and told Sherri that if she couldn't have John then no one could," said John Taylor, attorney for the Rasmussen family. "Stephanie Lazarus came to Glendale Advent, where [Rasmussen] worked and told her, 'If I can't have John, then no one can.'"
Taylor said the parents felt vindicated "to some degree" but added that they also believe the LAPD could have solved the crime earlier.
"There -- there's a lot of questions that the family still has," Taylor told ABC News. "There was an inordinate amount of information given to the LAPD back in 1986 which would have led them to look at Stephanie Lazarus before the time that they did.
"There had been this ex-girlfriend, their son-in-law's ex-girlfriend. And they wanted to know, had photographs been taken of this woman's [Lazarus's] body, which might indicate that she had been involved in a struggle."
But no matter how many times the family called the investigators -- and even wrote a letter out of frustration to the police chief -- they could not get the LAPD at the time to look beyond the burglary theory.
"Whenever [the father] would bring up the ex-girlfriend and ask, 'What's the status of the investigation about her?' he was told that he'd been watching too much TV," said Taylor.
Kennedy, Rasmussen's boss at the time, also has her questions. She reviewed the original coroner's report in order to process Rasmussen's life insurance policy.
"It was very obvious that there had been quite a struggle from the type of wounds that were described. ... Sherri was 6 feet tall, very athletic, and would have taken on a woman. It was really odd that she would fight with robbers with a gun, that didn't make a lot of sense."
Beck said it's difficult to judge police work in retrospect.
"You know, hindsight is 20/20," he said. "They were going down the wrong path, so, I mean, no matter how hard you work, it was just the wrong theory. And that's kind of -- that's one of the dangers that we talk about all the time in investigations is, don't get to -- don't fall in love with your own theories here."
The original detectives on the case are long retired. Beck said that police solidarity would not have been a factor in the case.