SAN FRANCISCO—Occupy Oakland protesters are suing the city of Oakland and Alameda County arguing that scores of arrests during a violent protest last year violated their civil rights.

A federal lawsuit filed Monday in San Francisco claims that 409 people were unlawfully arrested last Jan. 28, many at a busy intersection outside a YMCA just a few blocks from City Hall. The mass arrests followed hours of marches that included protesters trying to take over the vacant Henry J. Kaiser Convention Center.

The class-action suit, filed by one-time mayoral adviser Dan Siegel and Berkeley attorney Yolanda Huang, claims Oakland police officers and the Alameda County Sheriff's Department violated protesters' constitutional rights by conducting unlawful arrests and false imprisonments.

The suit said the protesters weren't given a dispersal order by law enforcement and that many of them were held in jail for hours but never charged with a crime.

As a result, the protesters' right to free speech, liberty and freedom from unreasonable searches and seizures were violated, the suit claims.

"You can't just arrest people because they are on a march; they have to be committing a crime," Huang told the Oakland Tribune on Tuesday. "It's a system of punishing people up front."

Alex Katz, spokesman for the Oakland City Attorney's Office, declined to comment, stating that the office had yet to see the complaint.

The suit seeks unspecified damages and an order sealing and destroying arrest records.

The suit stems from a march that started peacefully enough—a midday rally at City Hall and a march on a sunny Saturday afternoon.

But hours later, the scene near downtown Oakland dramatically deteriorated: clashes punctuated by rock and bottle throwing by protesters and volleys of tear gas from police, and a City Hall break-in that left glass cases smashed, graffiti spray-painted on walls and an American flag burned.

Hundreds of protesters were arrested on charges ranging from failure to disperse to vandalism, police said. At least three officers and one protester were injured during the melee.

At the time of the march, Occupy Oakland said it planned to use a vacant building as a social center and political hub for its activities and threatened to try to shut down the Port of Oakland for a third time, occupy the airport and take over City Hall.

After the arrests, the group criticized the police's conduct, saying that most of the arrests were made illegally because police failed to allow protesters to disperse.

But police told reporters later that night that protesters gathered unlawfully and police gave them multiple verbal warnings to disband.

In October, Oakland Police Chief Howard Jordan said he was seeking to fire two officers, demote a third and suspend 15 others for their treatment of protesters during unspecified Occupy demonstrations.

Jordan has since repeatedly pledged that the department will practice "constitutional policing."


Information from: San Francisco Chronicle,