Napa is joining Lake and Solano counties in a legal battle over whether to restore tribal status to Wappo Indians in Sonoma County’s Alexander Valley.

The three counties aim to thwart efforts by the Wappo tribe to regain tribal status, fearing it could open the door to Indian gaming in Napa and neighboring counties.

“They’re trying to assert that they have a tribe here in our county, along with Sonoma County and Lake County as well,” Napa County Supervisor Mark Luce said. “That ultimately could mean a casino somewhere where we wouldn’t want it.”

The Wappo tribe has never announced any plans for a casino in the area, but Napa County officials say it is a possibility they intend to nip in the bud.

“The problem is that once they receive tribal status, then it’s really out of our control,” Luce said. “They can say anything they want right now, and they’re not claiming they’re going to do anything like that, but it seems like there aren’t a lot of controls over that once tribes have been granted status.”

Representatives for the Wappo tribe did not return calls seeking comment.

Napa County formally joined the fight this week after a judge ruled that Napa, Sonoma and Lake counties can participate in legal proceedings initiated by the Wappo tribe last year.

The Mishewal Wappo Tribe of Alexander Valley filed suit against U.S. Interior Secretary Ken Salazar in 2009, claiming that its tribal status was illegally stripped in 1959 after Congress passed a law terminating the U.S. government’s recognition of their tribal sovereignty.

The Wappo tribe was granted 54 acres of land in Sonoma County more than a century ago by the U.S. Bureau of Indian Affairs, court records show. Anthropologists believe Wappos occupied a few miles of land on the south edge of Clear Lake, and a larger area extending from just north of Napa and Sonoma in the south to Coverdale and Middletown in the North.

The Wappos are asking the court to designate unspecified lands as “Indian country,” although Luce said it’s unclear which areas of Napa County would fall to the Wappos if they are granted tribal status.

The tribe is also asking a judge to grant the tribe special “protection, services and benefits of the federal government available to Indian tribes.” Among the benefits, the tribe could receive an exemption under the U.S. Indian Gaming Regulatory Act that would allow casino gambling on sovereign Wappo land.