Prosecutors declined Tuesday to file criminal charges against former U.S. Commerce Secretary John Bryson, saying a seizure caused a bizarre series of traffic collisions that led to his resignation.

Bryson's Lexus struck a car on June 9 that was stopped for a train in San Gabriel. He spoke briefly with the three occupants then hit the car again as he departed, police said. Bryson then rammed another vehicle in a neighboring city a few minutes later. He was found unconscious in his vehicle.

The Commerce Department said at the time that Bryson had a "limited recall of the events" and had not suffered any previous seizures.

Bryson, 68, was cited by police for felony hit-and run, and tests revealed he didn't have any alcohol or drugs in his system. Low amounts of Ambien were found in his bloodstream, but investigators couldn't determine if the sleep aid was a factor in the collisions.

"Both treating doctors agree that suspect was suffering from confusion following a seizure and crashed as a result," court documents say. "Based on doctors' opinions there is insufficient evidence to show knowing failure to provide personal information for hit-and-run."

Phone messages left for Bryson's wife, Louise, were not immediately returned.

Police in San Gabriel, a community of about 40,000 people northeast of Los Angeles, presented evidence Monday to county prosecutors, who decided against filing charges.

Police Sgt. Brian Kott declined to comment about the decision and said his department did not make any recommendations about filing charges.

"Our task was a fact-finding mission to complete a thorough investigation," he said

Bryson resigned as commerce secretary on June 21, saying then he had suffered a seizure and didn't want his health to be a distraction from his job. He had been in California to deliver the commencement address at Pasadena Polytechnic School, which his four children attended.

He is the former head of Edison International, the holding company that owns Southern California Edison, and has served on the boards of Boeing Co., Walt Disney Co. and major corporations.