SAN MATEO COUNTY — A Bay Area murder case that went unsolved for more than 30 years has finally been closed, according to the San Mateo County Sheriff’s Office.

Sheriff’s office investigators, in partnership with the Merced County Coroner’s Office, have concluded that Gregory Marc Riviera allegedly killed Juliette Rivera, 25, of Alameda, in the summer of 1992, the San Mateo County Sheriff’s Office said in a news release Tuesday.

Riviera died on Jan. 29, 2022. And when the Merced County Coroner’s Office conducted a fingerprint analysis to locate his next of kin, it discovered that his prints matched a wanted man who had been on the run for decades.

On July 7, 1992, Rivera was reported missing to police. During the course of their investigation, Alameda Police Department investigators began to suspect that Riviera, a then-50-year-old acquaintance of Rivera, was potentially involved in the young woman’s disappearance. According to the release, authorities found “numerous inconsistencies” in statements Riviera made.

A little over a week after Rivera went missing, a farm worker in a rural coastal area of unincorporated San Mateo County found the decomposed body of a young woman near an irrigation pond. The San Mateo County Coroner’s Office later identified the body as Rivera, and the autopsy showed she suffered blunt-force trauma from a flat object to her skull, the release said.

On Aug. 7, 1992, authorities issued an arrest warrant for Riviera, charging him with Rivera’s murder. But Riviera abandoned his Alameda apartment shortly before the warrant was issued. He had eluded law enforcement ever since.

In May of this year, the Merced County Coroner’s Office notified the San Mateo County’s Sheriff’s Office that the fingerprints of a recently deceased man, who went by “Jon Paul,” matched those of Riviera. In the investigation that later ensued, detectives learned that Riviera had a brother named John Paul and that he used his identity over the years to elude authorities.

Anyone with information related to the case can contact the San Mateo County Sheriff’s Office Investigations Bureau – Cold Case Unit at coldcase@smcgov.org.

Source: www.mercurynews.com