DNA Leads to Murder Charges in 2008 Tulare Cold Case

District Attorney Tim Ward has announced criminal charges related to the 2008 shooting death of Tulare man Hernan Diaz, age 21.

Luis Villarreal, age 34, is charged with one count of murder with the special allegations that he personally and intentionally discharged a firearm causing great bodily injury, that he possess multiple prior strike and violent felony convictions (assaults with a deadly weapon, 2007), and that he was on felony probation when the offense was committed.

It is alleged that late in the evening of August 12, 2008, at a Tulare apartment complex located at 1309 E. Birch, Villarreal shot Diaz multiple times through Diaz’s bedroom window with a .40 caliber handgun as part of a gang hit. Following the shooting, the Tulare Police Department collected evidence and interviews, but no arrest could be made at the time.

In 2019, the TCDA Bureau of Investigations formed a Cold Case Homicide Unit with the cooperation and mutual assistance with several allied agencies. This case represents the success law enforcement can have solving cases that have grown stale over time. In this case, a potential lead was discovered through the testing of DNA and Villarreal was identified as the person responsible for murdering Herman Diaz.

At the time charges were filed on July 8, 2022, Villarreal was in local custody for recent misdemeanor convictions. On July 11, 2022, Villarreal was arraigned on the charges and pleaded not guilty. He is currently held without bail. Villarreal is scheduled to return to court for a preliminary hearing conference on July 18, 2022, in Department 19. If convicted, Villarreal faces life in prison.

Media inquiries can be directed to the Office of the District Attorney, County of Tulare Assistant District Attorney Dave Alavezos (559) 636-5494