(Los Angeles-AP) -- Casino-owning Indian tribes have asked the state Supreme Court to block a ballot initiative that could break California tribes' monopoly on slot machines.

The five tribes say the initiative violates the state Constitution by deceptively combining "disparate subjects" and specifically benefiting "a small, identified group of private businesses" -- namely five racetracks and eleven card rooms.

Under the initiative those non-Indian operations would be allowed to have up to 30-thousand slot machines overall if tribes that operate casinos don't pay one-fourth of their earnings to the state.

An initiative spokeswoman says the tribes are just trying to avoid paying their fair share.

The initiative has not yet qualified for the November ballot.

(Copyright 2004 by The Associated Press.  All Rights Reserved.)