Bizarre twist helps solve 1992 Alameda cold case murder of Juliette Rivera

1992: KPIX coverage of Juliette Rivera slaying in Alameda

SAN MATEO (CBS SF) -- A suspect wanted in the 1992 Alameda murder of Juliette Rivera eluded authorities and arrest for decades by assuming the identity of his brother and living for years as a transient, cold case investigators revealed Tuesday.

Fingerprint analysis of a transient, who died in January in Merced County, proved to be the final piece of evidence that allowed detectives to bring an end to the cold case stemming back to July 7, 1992.

Juliette Rivera was reported missing on that day. At the time, Alameda police detectives contacted Gregory Marc Riviera, a 50-year-old acquaintance of Juliette's.

Juliette Rivera Family photo

During their investigation and questioning, numerous inconsistencies in Riviera's statements led police to suspect Riviera was involved in Juliette's disappearance.

On July, 17,1992, a farm worker in a rural area of unincorporated San Mateo County found the body of a badly decomposed young female near an irrigation pond. The body was later identified as that of Juliette Rivera. 

An autopsy showed Juliette suffered blunt force trauma from a flat object to the left rear skull.

San Mateo County Sheriff's detectives also began investigating the case and determined Gregory Marc Riviera was the suspect in the slaying and issued an arrest warrant.

By that time, Gregory Marc Riviera had already fled the Bay Area and his whereabouts remained a mystery for 30 years.

On May 12,  the San Mateo County Sheriff's Office received a call from the Merced County coroner telling them that the fingerprints on the body of a local transient known as Jon Paul came up as belonging to Gregory Marc Riviera.

In their investigation, detectives learned Gregory had a brother by the name of John Paul. 

Merced County coroner spoke to John Paul's daughter, and she confirmed John Paul was still alive, but suffering from medical issues.

She added Gregory and his brother had used each other's identity for the past 30 years to elude law enforcement.

Read more
f

We and our partners use cookies to understand how you use our site, improve your experience and serve you personalized content and advertising. Read about how we use cookies in our cookie policy and how you can control them by clicking Manage Settings. By continuing to use this site, you accept these cookies.