With a 6-1 vote, the California Supreme Court upheld the state's controversial Proposition 8, banning same-sex marriage, on Tuesday (May 26). According to the Los Angeles Times, the court also voted unanimously to keep intact the approximately 18,000 gay marriages that took place between June and November 2008.

The decision by the court -- the same one that voted a year ago that a state law defining marriage as the union of one man and one woman discriminated on the basis of sexual orientation -- is just the latest in a years-long struggle by both sides to decide the thorny issue. The ruling almost ensures yet another fight at the voting booth over gay rights in the most populous state in the country. The Sacramento Bee reported that gay-rights supporters gathered outside of the San Francisco courthouse where the ruling came down and chanted, "Shame on you, shame on you," as the decision was announced.

Gay-rights advocates have already vowed that they will ask voters to repeal the ban as early as next year, while opponents have promised to fight any such effort once again. After a contentious battle in the fall, [article id="1598657"]Proposition 8 narrowly passed in November[/article] with 52 percent of the vote. According to the San Francisco Chronicle, proponents of the ban spent $40 million in last year's campaign, while opponents spent $45 million.

A spokesperson for California Governor Arnold Schwarzenegger said the former actor-turned-Republican statesman was "hoping it would go the other way. But it didn't, and he will uphold what they have to say. ... He's always said it's not his job to impose that upon others, so he believes that someday soon, either the courts or the people will give same-sex individuals the right to marry. But it's his duty as governor to carry out whatever the Supreme Court says he needs to do."

Gay couples in California began getting married last June, after a state high court ruled 4-3 to strike down the marriage ban last May. In upholding Prop 8 on Tuesday, Chief Justice Ronald M. George wrote in the majority opinion that the November ballot initiative is not an illegal constitutional revision, as gay-rights lawyers had contended, nor is it unconstitutional because it takes away an inalienable right. The court's only Democrat, Justice Carlos R. Moreno, had wanted Prop 8 to be struck down, calling it an illegal constitutional revision that allowed the majority to deprive a minority of fundamental rights by passing an initiative, according to the Times.

Overturning the proposition was seen as a long shot, with no solid legal precedent available to gay-rights lawyers, and, in fact, some previous court rulings on constitutional revisions that undercut their arguments.

The twisted road to Tuesday's ruling began in 2004, when San Francisco mayor Gavin Newsom turned aside state law and allowed the city to begin issuing marriage licenses to gay couples. That action sparked a national debate about gay marriage, spurring dozens of states to adopt constitutional amendments banning same-sex unions. While the gay couples who'd gotten married in San Francisco later had their marriages rescinded by the California Supreme Court, the court also said supporters of gay marriage rights could challenge the ban in a lower court. The case bounced around in the courts several more times, before the [article id="1587558"]state high court ruled[/article] on May 15, 2008, that gay couples could marry.

At that time, California was one of only two states, along with Massachusetts, that permitted gay marriage. Since then, Connecticut, Iowa, Vermont and Maine have [article id="1608728"]legalized gay marriage[/article], and New York, New Jersey and New Hampshire are considering similar bills.