Ex-girlfriend of Aguirre says he told her he knew Doss at the time of her death as scientist testifies about lost condom

An ex-girlfriend of the former Pasco police officer on trial for the 1986 killing of Ruby Doss testified Thursday that Richard Aguirre told her he knew Doss at the time of her death.

DNA evidence linked Aguirre to the Doss killing in 2014, and he was charged with murder the next year. Those charges were dropped while investigators waited for more DNA testing, according to court records. Prosecutors refiled charges last year.

Doss, 27, was found beaten and strangled near Playfair Race Course on Jan. 30, 1986. Doss was working as a prostitute living in the El Rancho Motel with her daughter and boyfriend.

In the fourth day of his murder trial, Aguirre’s ex-girlfriend, Joan Thomasson, testified to statements Aguirre made shortly after DNA connected him to the case. The couple had broken up but were “cordial,” Thomasson said.

Thomasson said Aguirre admitted to having sex with Doss and that he had met her around the time of her death. He also made comments about throwing out a condom, Thomasson said.

Multiple friends and former co-workers of Aguirre testified to similar statements Wednesday.

Former Lifecodes forensic scientist Lisa Bennett testified she attempted to conduct DNA fingerprint analysis on the semen from the condom but couldn’t extract enough DNA.

Bennett told Prosecutor Stefanie Collins that she received the condom for testing in March 1989. The condom was then consumed during the testing process “based on my recollection and notes,” Bennett said without further explanation.

The word “consumed,” along with Bennett’s initials, and the date “3/3/89” were written on the envelope the condom arrived in, Bennett said.

Aguirre’s defense attorney John Browne also did not ask Bennett how specifically the condom was consumed during the testing protocol.

Dr. Veena Singh, Spokane County’s chief medical examiner, testified Doss’ cause of death was blunt force and asphyxial injuries.

Singh showed autopsy photos of Doss’ injuries, including bleeding in her brain that Singh said was caused by “significant force.” Doss’ hyoid bone in her neck was also broken as a result of strangulation, which could have been done by hand or with a ligature, she said.

Singh ruled Doss’ manner of death as homicide.

The trial is scheduled to continue next week.