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For Immediate Release

Petaluma Man Sentenced to 4 Years State Prison for Fatal Collision

SANTA ROSA, CA | July 13, 2022

Defendant James Thomas Watkins, 43 years old of Petaluma, was sentenced today by the Honorable Judge Bradford J. Demeo to serve 4 years in state prison after a jury returned a guilty verdict against him in May to charges of vehicular manslaughter with gross negligence in connection with a collision he caused in September of 2020 which resulted in the death of Mario Gongora Castaneda.

The charge resulted from the defendant’s negligent management of, and repeated concealment of, a seizure condition. His medical condition had resulted in numerous prior vehicle collisions, yet the defendant chose to continue driving. Further, the defendant concealed this condition from doctors, police, and the DMV.  During the incident, the defendant lost control while driving and struck Mr. Castaneda as Mr. Castandeda was taking his trash cans to the curb on McDowell Boulevard in the city of Petaluma.  The Petaluma Police Department responded to the collision and observed the defendant, the victim, and the victim’s family in a roundabout with emergency personnel attempting to save the victim’s life. The defendant appeared under the influence of a depressant, common for individuals in the later phases of a convulsive seizure. Based on the defendant’s repeated insistence that he did not have a seizure disorder; he was arrested for driving under the influence. However, it was later determined that the defendant did not have alcohol or controlled substances in his blood, besides low levels of his seizure preventative medication.

Further investigation of the defendant’s medical records, DMV records, other past reports to the Santa Rosa police, California Highway Patrol, and his insurance company ultimately revealed that he had been in at least one prior vehicle collision that involved concealing his seizure disorder. In addition, he lied about having this condition on his application for a driver’s license. The jury was not made aware of three additional collisions in the approximate two-and-a-half-year period prior to the fatal collision. However, the court was made aware of this fact at the time of sentencing. 

During the sentencing hearing the court heard from the victim’s son, daughter, and brother. The court also heard from the victim’s widow, who was with her husband at the time of the collision and witnessed these tragic events. 

The case was prosecuted by Deputy District Attorney Jason Rifkind, assisted by District Attorney Investigator Mike Phennicie.  The Petaluma Police Department headed the investigation.

Contact Information: 
Carrie Trevena 
Media Coordinator
Office of the District Attorney
(707) 565-3098