DNA database links retired Waco man to murders of sex workers in Texas and California dating back 30 years

WACO, Texas (KWTX) - A retired Waco man remains in the McLennan County Jail after the Texas Rangers cold case unit and west coast investigators linked him through a DNA database to the murders of prostitutes in East Texas and California 30 years ago.

Douglas Thomas, 67, was jailed this week under $2 million bond on a murder warrant from Titus County that charges him in the April 1992 death of Shenda Denise Hayes, according to a search warrant affidavit filed Wednesday by Texas Ranger Danny Briley.

The Ranger, who said in the affidavit that he investigates serial murders as part of the cold case unit, also alleged that Thomas was linked by DNA to the March 1993 murder of Sherri Herrera in Riverside County, California. Both women were described in the affidavit as “known prostitutes.”

Briley, the lead investigator in the 2013 shooting death of “American Sniper” author Chris Kyle, obtained a search warrant from 54th State District Judge Susan Kelly to extract a DNA sample from Thomas at the McLennan County Jail. Court documents show Briley took four swabs from Thomas’ mouth to get saliva samples.

Thomas was linked to the two murders by DNA samples from the crime scenes that had been uploaded years ago into the Combined DNA Index System, a national DNA database maintained by the FBI known as CODIS.

According to the affidavit, Hayes’ body was found near a rest area along Interstate 30 near Mount Pleasant in Titus County. An investigation showed she had been strangled “with a device made of wire and cord in a manner to control the victim,” the records state. She was found partially clothed with evidence of sexual assault.

Swabs taken from her body were uploaded into the DNA database in 2004, the Ranger said in the affidavit.

Mike Thompson, an investigator in the Riverside County District Attorney’s Office and a former member of the Riverside County Sheriff’s Department cold case unit, and Briley worked together on the case.

The 30-year-old Herrera’s body was found in March 1993 in a remote desert area along Interstate 10 in California. The affidavit says she was sexually assaulted and strangled with a belt. Court records identify her as a “known prostitute and drug abuser who worked the highway rest area” in Tulare County, Calif.

She was last seen being dropped off at a rest area between Tulare and Pixley, Calif., and had arranged to be picked up in 10 minutes, according to the affidavit. She was not seen again, the affidavit says.

Thompson reported that he uploaded a DNA profile from the murder scene in CODIS in 2002. Five years later, a “CODIS case-to-case hit,” or match, was made connecting the two murders.

“In other words, DNA from a single person was located at both crime scenes,” the affidavit states.

Thompson told Briley members of the Riverside cold case unit began conducting forensic genealogy probes on the Herrera and Hayes cases in September 2020. The Texas Rangers had already processed the evidence and obtained a single nucleotide polymorphisms file, Briley wrote in the affidavit.”The SNP is the specific type of file needed to upload into genealogical databases to obtain genetic matches,” according to the affidavit. “Thompson contacted a direct-to-consumer genealogical company that provides DNA kits to the general public for purchase for people to explore their genealogy.”

Thompson contacted Briley in Aprill to tell him that based on the “family tree” he built, there were six descendants who all live in or around Waco that were in the right genetic range for comparison. Briley, at Thompson’s request, took a DNA sample from Thomas on April 26, the results of which Briley said matches that of the “suspect profile.”

“Based on my training and experience and conversations with other professionals, including but not limited to Investigator Mike Thompson, the DNA match can only belong to Suspected Party,” Briley wrote in the court document.

Thomas is being held in jail on a Titus County murder warrant. However, prosecutors in McLennan and Titus counties said Thursday is has not been determined where his case will be handled.

Copyright 2022 KWTX. All rights reserved.