A Union City man is now facing a felony vehicular manslaughter charge after a high-speed, head-on collision on Highway 84 near Ruby Hill last summer that killed an Oakley man. Eduardo Guitierrez Delgadillo was notified of the single felony count following a yearlong California Highway Patrol investigation and a review by Alameda County prosecutors. The July 15, 2025 wreck left one driver dead and another critically injured, and has once again put a spotlight on reckless driving along the two-lane stretches cutting through the Tri-Valley.
According to Livermore Vine, the Alameda County District Attorney’s Office filed a single count of felony vehicular manslaughter with gross negligence on June 8. Court records indicate that Guitierrez Delgadillo, who is set to turn 21 this week, was advised of the charge by mail and does not yet have an attorney of record. His arraignment is scheduled for 9 AM on July 9 at the East County Hall of Justice in Dublin.
CHP investigators say the crash unfolded during the evening commute on July 15, 2025, when a westbound Lexus IS 250 crossed over into the eastbound lane and slammed into a Honda Civic, killing the Civic’s driver. In a probable-cause declaration, CHP Officer Gerardo Barajas wrote, “The GMC and the Lexus were traveling at a high rate of speed passing unsafely other motor vehicles,” and witnesses reported that the Lexus appeared to be racing a GMC Sierra, per Livermore Vine. The Lexus driver suffered severe injuries and was airlifted to a regional trauma center, while the pickup continued on and did not remain at the scene.
Investigators searching for pickup
Authorities appealed to the public for help tracking down the white 2015–2016 GMC Sierra described by witnesses, a lifted heavy-duty truck with black rims, oversized tires, a receiver hitch, tow mirrors and chrome bumpers, according to the Pleasanton Weekly. CHP officials said some bystanders captured video showing the Lexus driving recklessly before the collision and urged anyone with relevant footage or information to contact the CHP’s Dublin office.
What the charge could mean
Vehicular manslaughter with gross negligence is charged under California’s manslaughter statutes and requires prosecutors to prove a driver acted with a reckless disregard for human life. Jury instructions describe gross vehicular manslaughter as conduct that creates a high risk of death or great bodily injury. As outlined by CALCRIM, the offense is used when the facts indicate something beyond ordinary negligence. Legal summaries characterize the crime as a wobbler, meaning it can be filed as either a misdemeanor or a felony, and note that a felony conviction can carry a sentence of up to six years in state prison, per the Shouse Law Group.
Next steps
Guitierrez Delgadillo is expected in court on July 9 for arraignment, after which the case could move into pretrial hearings, plea talks, or a full trial, depending on how both sides proceed. Local coverage notes that the victim’s family organized a GoFundMe and remembered him as a loving big brother and son, while the CHP continues to seek witnesses and video as the investigation remains active. Community members and traffic safety advocates say the case highlights ongoing worries about high speeds and street racing on rural corridors throughout the Tri-Valley.
