But an attorney for San Ramon-based Chevron Corp. contended the takeover in May 1998 was "a hostile, illegal invasion that put workers' lives at risk."
The protest ended in violence when Nigerian Navy forces summoned by Chevron's Nigerian subsidiary shot and killed two protesters and wounded several others.
Today was the first day of a landmark trial on a human rights lawsuit filed by four protesters or their surviving family members.
The trial before a nine-member civil jury in the court of U.S. District Judge Susan Illston is expected to last five weeks.
Stormer said the more than 100 protesters, who were demonstrating against environmental damage and seeking jobs, carried only placards when they boarded the oil drilling platform, a barge and a tugboat nine miles offshore.
Mittelsteadt told the jury, however, that the protesters carried knives and poured diesel fuel on the barge and threatened to set it afire. He said that after the security forces arrived, some of the villagers escaped with the tugboat captain and crew and held them hostage for three more days.
Mittelsteadt said officials from Chevron's subsidiary who summoned the Navy didn't want or expect the incident to end violently, but had a duty to protect the company's workers and contractors.
The plaintiffs in the case include the families of one of the men killed in the incident and of a second protester who was allegedly tortured in a Nigerian prison and died three years later.
The other two plaintiffs are Larry Bowoto, who was shot and wounded, and another protester who was allegedly injured.