Here's an interesting post by Cheryl A. Schmit, Founder and Director of Stand Up for California.
"...As of February 2006, the CGCC had only completed six audits of the state’s 55 tribal casinos. The reason given for such lax oversight: the compacts failed to clearly establish the state’s role as independent regulator.
"What’s the effect of this? There have been numerous instances of corruption and theft in tribal casinos. One estimate is that the state received only half of the tribal casino revenues it was due under the 1999 compact. Unlike Las Vegas and other states, California tribal casino patrons have little assurance from independent regulators that the state’s tribal casinos are fair..."