In November 2008, a slim majority of California voters approved Proposition 8, which purports to add a single sentence to the California Constitution: "Only marriage between a man and a woman is valid or recognized in California." Various religious groups organized to place this initiative on the ballot in response to the California Supreme Court’s ruling in May 2008 that the state constitution guaranteed all citizens the fundamental right to marry, and that denial of this right to same-sex couples based solely on their sexual orientation violated the state constitution’s Equal Protection Clause. The California Constitution prescribes two separate mechanisms by which it can be changed: amendments, which may be effected by ballot initiative, and revisions, which must first be approved by a majority of the state legislature. Immediately after Proposition 8 passed, same-sex couples, municipalities, and progressive advocacy groups filed petitions with the California Supreme Court, urging it to exercise its jurisdiction to nullify Proposition 8 on procedural grounds. Despite its brevity, they argued, Proposition 8 would effect a fundamental change to the state constitution by gutting its equal protection principle — some Californians would now be more "equal" than others. Consequently, Proposition 8 comprised a revision, not an amendment, and was invalid absent prior legislative approval. In an amicus brief supporting these petitioners, we argued that by purporting to create an exception to equal protection, one of the California Constitution’s bedrock principles, Proposition 8 eviscerated it. If allowed to take effect, Proposition 8 would set a dangerous precedent for the piecemeal withdrawal of fundamental rights from other disfavored minorities, including religious ones, by simple majority vote. In creating a constitutional scheme that distinguished between amendments and revisions, the People had wisely prescribed a more rigorous and deliberative procedure for accomplishing such radical changes as those that Proposition 8 would effectuate. While Proposition 8 had, barely, achieved popular support, the People’s will, as expressed in California’s founding document, mandated its nullification. The brief was filed on January 15, 2009, on behalf of Americans United and a broad coalition of civil rights groups. The California Supreme Court heard oral argument on March 5, 2009. On May 26, 2009, the Court upheld the Proposition 8 ballot initiative, but held that same-sex marriages already performed while they were legal would remain in effect.