Former LAPD detective Stephanie Lazarus to be sentenced in murder case

(CBS/AP) LOS ANGELES - Former Los Angeles police detective Stephanie Lazarus faces 27 years to life in prison when she's  sentenced Friday for murdering the wife of her former lover in 1986.

Watch the 48 Hours episode about the Stephanie Lazarus case: "One of Their Own"

Lazarus was found guilty in March of killing Sherri Rasmussen, who was bludgeoned and shot to death 26 years ago in the condo she shared with her husband of three months, John Ruetten.

Detectives initially believed two robbers who had attacked another woman in the area were to blame. But two decades later, a cold case team using DNA analysis concluded the killer was a woman and authorities began looking at Lazarus as a suspect.

During the trial, prosecutors focused on the relationship of Lazarus and Ruetten, who were lovers after they graduated from college.

Ruetten testified that he never intended to marry Lazarus, although they were intimate for about a year. He also said she enticed him into having sex with her shortly before his wedding.

"Here's the deal," he testified. "It was clear she was very upset that I was getting married and moving on."

The case hinged on a single piece of evidence: DNA from a bite mark on Rasmussen's arm that prosecutors say belonged to Lazarus.

Lazarus's attorney argued the DNA evidence was corrupted and not reliable evidence.