calsupremesAll eyes interested in the gay-marriage debate will be on San Francisco today, where the California Supreme Court (pictured) convenes and where it will release its long-awaited ruling on whether gays and lesbians have a constitutional right to marry in California. The ruling is due at 1 p.m. EDT.

What we want to do in this post: to get you fully up to speed on the case itself before the ruling comes down. Thanks to this article in today’s San Francisco Chronicle, we can. Here goes:

  • In 2000, Californians voted to reaffirm a 1977 state law that defines marriage as the union of a man and a woman. The 2000 initiative, called Proposition 22, was not a constitutional amendment.
  • In February 2004, San Francisco mayor Gavin Newsom told the city clerk to issue marriage licenses to same-sex couples, saying he doubted the constitutionality of the 1977 law. Gay and lesbian weddings ensued.
  • The California Supreme Court stopped the weddings a month later, then nullified the marriages in August 2004, ruling that Newsom lacked the authority to override California law.
  • The court did not rule on the validity of the law, however, and kicked the issue to the lower courts. Nearly two-dozen gay and lesbian couples — including some whose marriages had just been annulled — and by the city of San Francisco, then sued to challenge the law.
  • A Superior Court judge in San Francisco declared the ban on same-sex marriage unconstitutional in March 2005. Judge Richard Kramer said the law violated the right to marry the partner of one’s choice and also constituted sex discrimination.
  • But a state appeals court reversed Judge Kramer’s ruling, upholding the law in October 2006. The court said California is entitled to preserve the historic definition of marriage while protecting gays and lesbians from discrimination by granting marital rights to domestic partners, most of whom are same-sex couples.

That, alas, is the argument advanced by state Attorney General Jerry Brown’s office, which is defending the marriage law. Opponents argue that the law violates California’s constitution.

But here’s a catch: Even if the court votes to overturn the appellate court ruling and invalidate the 1977 law, the ruling might not stick. “Pro-family” organizations have submitted more than 1.1 million signatures for an initiative that would amend the state Constitution to outlaw same-sex marriage. If at least 694,354 signatures are found to be valid, the measure would go on the November ballot and, if approved by voters, would override any court ruling in favor of same-sex marriage.

Anyway, what’s to be expected in today’s ruling? According to the Chronicle, the current court has a 6-1 majority of Republican appointees, but has a centrist record on social issues and has ruled in favor of gay-rights advocates in a number of cases, including three decisions in 2005 requiring equal treatment for same-sex parents in disputes over child support and custody. The justices seemed sharply divided at their hearing in the marriage case March 4.

Massachusetts is the only state whose high court has ruled that the state’s Constitution gives same-sex couples the right to marry.