Washington — Indian tribes are subject to federal labor law, an appeals court ruled Friday in a case that could lead to stricter labor protections – and more unions – at the nation’s booming Indian casinos, including Connecticut’s.

A three-judge panel of the U.S. Court of Appeals for the District of Columbia Circuit rejected arguments from a wealthy Southern California tribe that as a sovereign government, it should not be subject to those laws.

„Tribal sovereignty is not absolute autonomy, permitting a tribe to operate in a commercial capacity without legal constraint,“ said the opinion written by Judge Janice Rogers Brown.

The ruling stemmed from an organizing dispute at a casino run by the San Manuel Band of Mission Indians, 60 miles east of Los Angeles, where a union filed a complaint with the National Labor Relations Board arguing that another union was getting preferential access.

San Manuel contested the complaint by asserting that the labor board didn’t have jurisdiction because federal law recognizes Indian tribes as sovereign governments.

The labor board disagreed in a 2004 opinion that, for the first time, said tribes are covered by the National Labor Relations Act, which bars unfair labor practices and gives workers the right to organize and bargain with employers.

Connecticut sided with the labor board and intervened in the case. The ruling has broad implications for both Connecticut Indian casinos, Attorney General Richard Blumenthal said Friday.

„This historic victory opens a new era for working men and women at tribal casinos in Connecticut and across the country,“ Blumenthal said. „While we respect the principles of tribal sovereignty, this ruling guarantees basic rights deserve respect, no matter who the employee.“

Employees at Foxwoods Resort Casino in Mashantucket, where workers are not unionized, have already clashed with management over wages and benefits. Nearly 400 workers called in sick over the busy New Year’s holiday in protest of what they said were declining benefits and compensation.

The casino, which employs more than 11,000 people, announced almost a month later that it would be replacing the Employee Group Council of workers, which has spoken on behalf of casino employees for more than 10 years, with worker „focus groups.“ Casino officials said the new groups would work on improving communication, increasing job satisfaction and maintaining a safe work environment.

A spokesman for the casino did not return calls Friday evening. Officials at Mohegan Sun, whose 10,000 workers are also not unionized, declined to comment on Friday’s ruling.

At stake are protections and bargaining rights for about 250,000 workers, most of them non-Indians, at the nation’s 400-plus tribal casinos. The ruling comes as tribal gambling has exploded into a USD 22 billion-a-year industry – richer than Las Vegas – with Indian casinos in 28 states.

A few tribal casinos in California are unionized, including San Manuel, but most workers at Indian casinos are nonunion. Unions have been trying hard to make inroads with the growing workforce but say they’ve had trouble without the protection of the National Labor Relations Act.

Even though San Manuel employees already have joined Communications Workers of America, the ruling could undercut the tribe’s ability to deal with the union on the tribe’s own terms, which critics say favor the tribe. The tribe contends it treats its workers well, and employees at the San Manuel casino have praised conditions there.

„We are disappointed by the ruling today,“ said Henry Duro, chairman of the San Manuel tribe, which was backed in the case by the National Indian Gaming Association and leading tribes.

„We believe that these gaming projects help tribes to fulfill essential governmental functions by providing education, health care, housing, senior care and other key programs,“ Duro said. „Those are basic governmental obligations that could be impacted by this decision.“ A tribal spokesman said the tribe hadn’t decided whether to appeal.

Jack Gribbon, political director for Unite Here in California, said the ruling came down on the side of „workers who are the engine behind the extremely lucrative tribal gaming industry.“

If the ruling stands and tribes don’t come to the table, „it creates the opportunity for a major clash, for disputes and unrest and picketing and striking,“ Gribbon said.

The appeals court said San Manuel read too much into the fact that the 1988 Indian Gaming Regulatory Act permits tribes and states to regulate Indian casinos. „It is a considerable leap from that bare fact to the conclusion that Congress intended federal agencies to have no role in regulating employment issues that arise in the context of tribal gaming,“ said the 23-page order.

Also on the appeals panel were Judges Stephen F. Williams and Merrick B. Garland.