The measure amends the California Constitution and state statute to prohibit any gambling compact that would allow a tribal casino located in an “urban area.” The measure defines urban area to mean all land within 15 miles of an area determined by the 2000 U.S. Census to be an “urbanized area” (generally having a population of at least 50,000 people). The measure would not apply to any land of a tribe that, as of January 1, 2005, was eligible for gambling (by means of an existing compact). For any compacts affecting urban land that the state “must negotiate” (not defined by the measure), the measure requires the compacts to be approved by two-thirds votes of each house of the Legislature.