OAKLAND -- Jurors began hearing testimony Monday at the trial for a Tuolumne County man who claims he was acting in self-defense when he shot at California Highway Patrol officers during a 2010 gunbattle on Interstate 580 in Oakland.

Byron Williams, 48, is facing life in prison if convicted of the attempted murders of Officers Vincent Herrick, Marcus Holden, Ty Franklin and Todd Owen. They were among more than a dozen officers present during gunfire exchange with Williams on July 17, 2010, on westbound I-580 near the Harrison Street onramp after what was expected to be a routine traffic stop for speeding and weaving.

Byron Williams, the suspect in the CHP shootout on I-580 Saturday, July 17, 2010. This is a photo from a 2002 arrest in Madera County. (Madera County
Byron Williams, the suspect in the CHP shootout on I-580 Saturday, July 17, 2010. This is a photo from a 2002 arrest in Madera County. (Madera County Sheriff's Dept.)

"I was afraid for my life, his life, everybody driving around. I was afraid someone was going to get hurt or killed," said Herrick, describing how Williams pointed a handgun at him after he opened Williams' passenger-side door to move to a safer location than the slim freeway shoulder and spotted a shotgun and alcohol. Herrick said he was ducking for cover when he heard Williams fire a shot and Holden return fire.

Williams, armed with three loaded firearms and wearing a bulletproof vest, told investigators that he was pulled over while he was on his way to San Francisco for a confrontation at the Tides Foundation, which supports nonprofits working toward social change, or the American Civil Liberties Union. Authorities have said Williams intended to "start a revolution."

"He was looking for the people in charge" and told police that he fired at the CHP officers "because I knew where this was going and I wasn't going to get arrested," Alameda County deputy district attorney Autrey James told jurors in his opening statement.

Herrick and Holden had nearly emptied three magazines shooting at Williams and was almost out of ammunition before backup arrived around midnight to help them and shut down the freeway.

The gunbattle had gone on for about 20 minutes by the time a wounded Williams surrendered. In the end, 10 officers fired upward of 200 rounds, while Williams fired about 10. He was hospitalized with gunshots to his head and foot. Officers Owen and Franklin were briefly hospitalized; Owen's leg was hit with shrapnel during the shooting, and Franklin's eye was hit by shattered glass.

Defense attorney Eric Schweitzer told jurors they should discount Williams' alleged confession from his hospital bed because he was on hospital-grade narcotics and was very susceptible to his interrogators' suggestions. He said that the shooting did not go down as told by officers and that the Oakland police investigation into the incident was compromised by the CHP's interference.

In Williams' account, Herrick pulled a gun on him after seeing his shotgun and the next thing he knows he is suffering from a debilitating wound on the back of his head. Williams fired at the officers to "forestall his immediate execution" but never aimed at anyone, the defense attorney said.

"A man has a right to defend his life," Schweitzer said.

Williams is also being tried on three counts of being a felon in possession of a firearm and one count of possession of ammunition. At the time of his arrest, he was an unemployed carpenter with two previous convictions for bank robbery.

Contact Malaika Fraley at 925-234-1684. Follow her at Twitter.com/malaikafraley.