Provides that only marriage between one man and one woman is valid or recognized in California. Prohibits decreasing marriage rights shared by one man and one woman. Defines man and woman. Voids or makes unenforceable certain rights and obligations conferred by California law on same-sex and opposite-sex couples registered as domestic partners, concerning subject areas including, but not limited to, community property, intestate succession, stepparent adoption, child custody, child support, hospital visitation, health care decisions for an incapacitated partner, insurance benefits, death benefits, and recovery for wrongful death. Summary of estimate by Legislative Analyst and Director of Finance of fiscal impact on state and local governmen...