Dublin, CA – Alameda County District Attorney Nancy E. O’Malley announced today that her office has filed multiple felony sexual assault charges against Livermore resident Gregory Paul Vien, based on crimes committed against two women in 1997 in the cities of Livermore and Union City, CA.
On May 6, 1997, the defendant attacked a woman as she walked to BART after work. He dragged her to a secluded area where he sexually assaulted her. Union City Police detectives were able to obtain a sample of the suspect’s DNA from the victim’s clothing. On September 7, 1997, the defendant attacked a second victim while she was on a walk near Livermore High School in the city of Livermore. The defendant sexually assaulted the victim, and the Livermore Police Department was able to collect a DNA sample from the crime scene.
The DNA samples from both crime scenes were analyzed in a timely manner, and found to be a match to each other, meaning that law enforcement knew that the same person was responsible for both assaults. The samples were uploaded to CODIS, the national DNA data base. However, no “hit” was made to determine the identity of the assailant.
In 2019, detectives from the Livermore Police department developed additional leads through a genetic genealogical search in their quest to solve these 22-year old sexual assault crimes. Those leads enabled additional investigation with a focus on Mr. Vien and the eventual collection of Mr. Vien’s DNA sample, ultimately identifying him as the assailant in both crimes.
“For over 20 years, the survivors of these sexual assaults have lived with the constant uncertainty that comes with not knowing when, if ever, their assailant will be identified and brought to justice,” states DA O’Malley. “The police agencies never gave up, nor let these investigations go cold. Their dedication, tenacity and excellent investigative work, has now paid off in the arrest of Mr. Vien. My office’s specialized cold case unit and sexual assault unit worked alongside our law enforcement partners and will now ensure that Mr. Vien is held to account for the crimes he committed.”
The defendant was arraigned on November 7, 2019. His next court date is set for November 20, 2019 at the East County Hall of Justice in Dublin, CA.
Anyone who believes he or she has additional information is asked to contact Sgt. Steve Goard of the Livermore Police Department at 925.580.9585 or at [email protected]
According to the 11-page complaint:
On May 6, 2017, Union City Police officers began investigating a sexual assault after the victim told officers she had been violently attacked by an unknown male and dragged into a secluded area where the suspect cut the victims clothes off of her using a knife and sexually assaulted her (digital penetration and forced oral copulation). The victim told officers the she spit the suspects ejaculate out of her mouth and onto the inside portion of her jacket. This item was collected and preserved as evidence. In 1997, the jacket was taken to the crime lab but no match was found.
In June 2019, a possible suspect was identified through a private DNA database. That suspect was identified as Gregory Paul Vien. Vien had lived approximately 3-miels from the Livermore assault. Detectives collected surveillance and items were collected including a Baskin Robbins spoon which created a DNA match from the assault and connected him to the likely suspect linked to the semen stain found at the Livermore rape scene.