Petaluma man sentenced to 4 years in prison in 2020 fatal collision

SANTA ROSA – A Petaluma man has been sentenced to four years in prison for a fatal collision that occurred in 2020, the Sonoma County District Attorney’s Office announced Wednesday.

James Thomas Watkins, 43, was found guilty in May of vehicular manslaughter with gross negligence.

Mario Gongora Castaneda was killed in the collision, which occurred in September 2020.

Prosecutors said Watkins was charged in the fatal collision because of his negligent management of and repeated concealment of a seizure condition.

The condition resulted in numerous prior vehicle collisions, but Watkins chose to continue driving and concealed the condition from doctors, police and the state Department of Motor Vehicles.

The collision occurred when Watkins lost control of his vehicle while driving and struck Castaneda as he was taking his trash cans to the curb on McDowell Boulevard in Petaluma.

Following the collision, the defendant appeared to be under the influence of a depressant common for individuals in the later phases of a convulsive seizure, according to the district attorney’s office.

Watkins repeatedly insisted he did not have a seizure disorder and was arrested on suspicion of driving under the influence, but investigators later determined the defendant did not have alcohol or controlled substances in his blood other than low levels of a seizure preventative medication.

Further investigation revealed Watkins had been in at least one prior vehicle collision that involved concealing his seizure disorder and had lied about his condition on his application for a driver’s license.