How Riverside County’s cold case team and Texas Rangers brought a killer in a 32-year cold case to justice
Garrett Hottle
RIVERSIDE, Calif. (KESQ) – A three-decade-old murder case in the Coachella Valley is moving forward in court after investigators used DNA technology to identify a long-haul truck driver as the suspect.
On March 30, 1993, the body of 30-year-old Sherri Herrera, a mother of four from Tulare, was discovered off the eastbound Hayfield Road on-ramp to Interstate 10 in Desert Center.
Prosecutors say she had been sexually assaulted and strangled.
For years, the case went unsolved. But in 2022, Riverside County’s Regional Cold Case Homicide Team worked alongside the Texas Rangers, using forensic genetic genealogy to connect the crime to 71-year-old Douglas Thomas, a truck driver already convicted of a separate 1992 murder in Titus County, Texas.
“In 2022, working with the Texas Rangers, we were able to determine this person was the killer,” explained, Supervising Investigator Billy Hester with the Riverside County District Attorney’s Office. “After three decades, DNA gave us the breakthrough we needed,”
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Detectives traveled to Texas to interview Thomas before California prosecutors filed charges. He was transferred to Riverside County last month through an interstate detainer process.
Thomas has since pleaded not guilty to Herrera’s murder, along with a special circumstance allegation that the killing happened during the commission of a rape.
Hester said solving cold cases often comes down to timing and persistence.
“One of the most challenging things about cold cases is we’re racing against the clock,” he said. “Memories fade, witnesses die. So when we finally identify a suspect, it feels like we can bring justice for the victims and closure to the families,” he said.
Thomas remains held in Riverside County custody ahead of a felony settlement conference scheduled for December 3 at the Riverside Hall of Justice.
Tune into News Channel 3 tonight at 5pm and 6pm to hear more on the Riverside DA’s Office’s efforts in the case.