Inmate pleads no contest to role in 1988 Petaluma rape and murder

A state prison inmate admitted his role Thursday in a quarter-century-old Petaluma homicide that baffled detectives for years until he and an accomplice were identified through DNA evidence.

Josafat Presencion, 49, pleaded no contest to involuntary manslaughter, rape and other charges in the 1988 slaying of Wynetta Davis, 26, of Vallejo, whose body was discovered in a water trough off Pepper Road near Bodega Avenue.

Her death went unsolved until two years ago when detectives revisiting old cases submitted samples that led to Presencion and a co-defendant, Fausto Chavez, 50.

At the time, Presencion was serving a 25-year sentence at San Quentin State Prison for a Marin County rape.

Now, he will remain behind bars for an additional period equal to half his new punishment, or about 13½ years, prosecutor Jason Riehl said.

Riehl said the age of the case was a factor in deciding not to push for a murder conviction.

“This plea holds him accountable for crimes we believe he committed,” Riehl said. “Public safety-wise, it ensures he is off the streets for a lengthy period of time.”

He will be sentenced Aug. 4.

Davis was reported missing May 11, 1988. The mother of two left her south Vallejo home to buy diapers and never came back.

Her body was discovered two days later 40 miles away in the livestock water trough. The cause of death was asphyxiation or “dry drowning,” Riehl said.

Detectives were unable to find any suspects and the case went cold. Then, in 2010, the sheriff’s office reopened a number of old cases to see if advancements in DNA technology could help.

Presencion, who had been in prison since 1989, and Chavez, 50, were indentified as suspects.

Both were initially charged with murder. Chavez testified at a preliminary hearing that Presencion was responsible. He said the three drove to Petaluma to party and to have sex. Davis was killed in a dispute, he said.

Chavez pleaded no contest to being an accessory after the fact in a deal to cooperate with prosecutors.

On Thursday, Presencion pleaded no contest to voluntary manslaughter with a prior, forcible rape and oral copulation.

Because the crimes took place under old sentencing laws, Presencion may be released after serving half the punishment, said his lawyer, Geoffrey Dunham.

You can reach Staff Writer Paul Payne at 568-5312 or paul.payne@pressdemocrat.com. On Twitter @ppayne.