A judge has ruled that Sonoma, Napa and Lake counties can join a court fight over federal recognition of Alexander Valley's Wappo Indian tribe.

The counties fear recognition of the Wappos will lead to another tribal casino.

The Wappos filed suit last year against U.S. Interior Secretary Ken Salazar, charging they were unlawfully stripped of their tribal status in 1959.

They're asking the Interior Department to restore their tribal rights, benefits and historic lands. The lawsuit — if successful — also would authorize casino gambling on the Wappos' lands under the U.S. Indian Gaming Regulatory Act.

A conference in the case was scheduled for Monday in U.S. District Court in San Jose, but was postponed until June 28 to give Sonoma, Napa and Lake counties more time to prepare.

On May 26, Judge James Ware granted the counties' motions to intervene in the case, noting there was no opposition from the tribe or the Interior Department.

"The county is pleased," said Jeffrey Brax, a Sonoma County deputy county counsel. "Our goal is to play an active role and ensure that the rights of the county and its citizens are protected."

Federal recognition of the Wappos could pave the way for a tribal casino or other commercial development, he said.

In motions filed earlier this year, Sonoma, Napa and Lake counties said lands shouldn't be taken out of their jurisdiction without consultation.

Sonoma County said the tribe's lawsuit would allow casino-style gambling "with no review by the county or other affected parties."

A casino on restored tribal land would impose "massive new obligations" on local services while removing property from the tax base, Sonoma County attorneys said.

Earlier this year, Wappo tribal chairman Scott Gabaldon said the tribe won't decide on its future plans until it regains federal recognition.

The Wappos once occupied a large portion of Napa, Sonoma and Lake counties, according to anthropologists.

The U.S. Bureau of Indian Affairs established a 54-acre reservation for the Wappos starting in 1908, on West Soda Rock Lane near the Russian River northeast of Healdsburg. But their Alexander Valley Rancheria lost its tribal status in 1959 after Congress passed a law aimed at privatizing California's small Indian communities.

The Wappos' lawsuit said they weren't properly notified and the government broke a promise to improve roads, water and sanitation. The government distributed most of the land to non-Indians after the tribe disbanded, according to the lawsuit.

The Interior Department denied the allegations, but the two sides have been discussing a settlement, according to court records.