GILROY, Calif. (KRON) — A woman murdered by “The Happy Face Serial Killer” has been identified 29 years after her violent death, the Santa Clara County Sheriff’s Office said.

Her body was found on the side of Highway 152, also known as Pacheco Pass, on the outskirts of Gilroy on June 3, 1993. She was dressed in blue clothing.

Instead of “Jane Doe,” cold case detectives referred to her as “Blue Pacheco” for nearly 30 years.

At first, both the woman’s identity and cause of death were mysterious. The Santa Clara County Medical Examiner-Coroner’s autopsy classified her cause of death as “undetermined.”

In 1994, an anonymous person sent letters to an Oregon newspaper claiming to be a serial killer who murdered many women along the West Coast.

All of the letters were signed with a drawing of a happy face.

“The Happy Face Serial Killer” was later identified by law enforcement as Keith Hunter Jesperson.

The Clark County Sheriff’s mug shot of Keith Jesperson

An extensive investigation into Jesperson confirmed that he murdered at least eight women, the Sheriff’s Office said. The long-haul truck driver’s killing spree lasted from 1990 until 1995, when he turned himself in to law enforcement. 

Jesperson bragged about his killing spree in his letters to the newspaper. But he did not mention the woman left dead on Pacheco Pass.

In 2006, Jesperson wrote more letters, this time to the Santa Clara County District Attorney’s Office. He admitted to sexually assaulting and killing a woman along a dirt turnout on Highway 152, according to the Sheriff’s Office.

The serial killer did not know what his victim’s name was. Jesperson pleaded guilty to killing “Blue Pacheco” in 2007.

Convicted murderer Keith Jesperson smiles at his attorney on Nov. 2, 1995 while making court appearance in Portland, Oregon. (AP Photo / Don Ryan)

In 2019, Santa Clara County Sheriff cold case detectives re-evaluated the “Blue Pacheco” case to follow-up on leads, used advanced investigative genetic genealogy, and partnered with the DNA Doe Project.

The mystery of her identity was finally solved last week. “Blue Pacheco’s” real name was Patricia Skiple, according to the Sheriff’s Office.

Her friends and family called her “Patsy.” Skiple was a mother, a long-term resident of Colton, Oregon, and was 45 years old, investigators discovered.

“Blue Pacheco” was identified as Patricia Skiple, 45, of Colton, Oregon. (Santa Clara County Sheriff’s Office)

“Although this criminal case was adjudicated, detectives never gave up as they worked diligently throughout this investigation to provide closure for the family of Patricia Skiple,” the Santa Clara County Sheriff’s Office wrote.

Jesperson, 67, is currently serving five life sentences in an Oregon state prison.