California politics is under fire as officials face fraud accusations while state moves to block outside investigators — bad news for the state's leadership.

• A former California aide, Daniel Williamson, is expected to plead guilty and may cooperate with prosecutors to avoid heavy prison time.
• Critics say the state is trying to shield rampant fraud from scrutiny.
• California moved to stop the so-called Nick Shirley Act, which would have made it easier to investigate fraud.
• The claim is that blocking investigators protects officials rather than the public.

Outlook: If Williamson cooperates, more California officials could face charges in the months ahead.