LOS ANGELES (CBS) — Attorneys are delivering closing arguments in the murder trial of an LAPD detective who is accused of killing her ex-boyfriend’s wife.

Stephanie Lazarus, 51, is charged in the 1986 murder of 29-year-old nursing supervisor Sherri Rasmussen, who was shot to death in Van Nuys.

Prosecutors argued Monday that Lazarus thought she committed the perfect murder 26 years ago, which they describe as a willful and an intentional cold-blooded act.

The murder case was cold until DNA evidence led to Lazarus’ arrest in 2009.

Investigators say Rasmussen had a bite mark on her arm that has now been linked to Lazarus.

The former art theft investigator retired from the LAPD after her arrest.

A jury of eight women and four men could get the case as early as Tuesday.