The suit claims that the measure violates California’s constitutional law regarding ballot initiatives, which states that each initiative can only contain one subject.

Tribal casinos and cardrooms have long been embroiled in disputes over the legitimacy of cardrooms offering casino games.

The measure would also give exclusive rights to tribal casinos to offer roulette and dice games such as craps, while California cardrooms will not be allowed to offer these games. A referendum on sports betting legalization in California will take place in November if enough signatures are gathered in support of the ballot. It aims to halt the California Sports Wagering Regulation and Unlawful Gambling Enforcement Act, which could appear on the November ballot. The suit was filed at the Los Angeles Superior Court. Two cardrooms, Hollywood Park Casino and Cal-Pac Rancho Cordova, have filed a lawsuit challenging an initiative that would legalize sports betting in California and allow tribal owned casinos to sue cardrooms.

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