In the sprawl of Los Angeles County, a handful of casinos have operated for decades.

There’s the crescent-shaped casino in Commerce, an industrial city off Interstate 5. A warehouse-like gambling parlor in Hawaiian Gardens, a short drive south. Two card rooms in Gardena, a nearby suburb.

Beyond being places to gamble and unwind, they have two things in common. They generate a large portion of their cities’ revenue. And their existence may soon be challenged in court by California’s tribal nations.

After a multimillion-dollar lobbying battle, state legislation signed into law last month allows Native American tribes, which own some of California’s largest and most lucrative casinos, to dispute the legality of certain games played inside these small, privately owned gambling halls.

Tribes have argued that such casinos — also known as card rooms because they have only table games and not slot machines — have siphoned millions of dollars away from them.

The new law opened a window until April 1 for tribes to take their case to state courts, where they had lacked legal standing. At particular issue is whether the card rooms offer games considered Las Vegas-style gambling, to which the tribes have exclusive rights in California.

A group called the California Cardroom Alliance has said the law puts jobs at risk.