by Bob Egelko

SAN FRANCISCO - Gays and lesbians have a constitutional right to marry in California, the state Supreme Court said today in a historic ruling that could be repudiated by the voters in November.

In a 4-3 decision, the justices said the state's ban on same-sex marriage violates the "fundamental constitutional right to form a family relationship." The ruling is likely to flood county courthouses with applications from couples newly eligible to marry when the decision takes effect in 30 days.

The ruling set off a celebration at San Francisco City Hall. As the decision came down, out-of-breath staff members ran into the mayor's office where Gavin Newsom read the decision.

Outside the city clerk's office, three opposite-sex couples were waiting at 10 a.m. for marriage certificates. City officials had prepared for a possible rush on certificates by same-sex couples, but hadn't yet changed the forms that ask couples to fill out the name of the "bride" and "groom."

Kenton Owayang, the office supervisor for the city clerk's office, said he's waiting for word from the state registrar's office about marriage forms and working on getting extra staff members in today in case the city is able to give out the certificates to same-sex couples.

Ed Harrington, the general manager of the city's Public Utilities Commission, was one of the staff members in the mayor's office shortly after the decision was released. Harrington has lived with his partner for 35 years and in 2004 Harrington married about 40 same-sex couples.

"You wait for this your whole life," said Harrington, who said he planned to call his partner and say, "I love you. What more do you say on a day like this?"

The PUC chief said he's unsure if he'll get married if Newsom resumes the City Hall marriages. "What's important is to be able to (get married) if you want to," he said.

The celebration could turn out to be short-lived, however. The court's decision could be overturned in November, when Californians are likely to vote on a state constitutional amendment banning same-sex marriages. Conservative religious organizations have submitted more than 1.1 million signatures on initiative petitions, and officials are working to determine if at least 694,354 of them are valid.

If the measure qualifies for the ballot and voters approve it, it will supersede today's ruling. The initiative does not say whether it would apply retroactively to annul marriages performed before November, an omission that would wind up before the courts.

The legal case dates back to February 2004, when Newsom ordered the city clerk to start issuing marriage licenses to couples regardless of their gender, saying he doubted the constitutionality of the state marriage law.

The state's high court ordered a halt a month later, after nearly 4,000 same-sex weddings had been performed at San Francisco City Hall. The court annulled the marriages in August 2004, ruling that Newsom lacked authority to defy the state law. But it did not rule on the validity of the law itself and said it would await proceedings in lower courts.

Some of the couples immediately sued in Superior Court and were joined by the city of San Francisco, which said it had a stake in ensuring equality for its residents. The case that ultimately reached the state Supreme Court consolidated four suits, one by the city and three by 23 same-sex couples in San Francisco and Los Angeles.

Superior Court Judge Richard Kramer, ruling in the San Francisco cases, declared the ban on same-sex marriage unconstitutional in March 2005. He said the law violates the "basic human right to marry a person of one's choice," a right declared by California's high court in 1948 when it became the nation's first court to overturn a state ban on interracial marriage.

Kramer said the law also constitutes sex discrimination - prohibited by another groundbreaking California Supreme Court ruling in 1971 - because it is based on the gender of one's partner.

But a state appeals court upheld the law in October 2006, ruling 2-1 that California was entitled to preserve the historic definition of marriage and that the state's voters and legislators, not the courts, were best equipped "to define marriage in our democratic society."

The appeals court also said California is not discriminating against same-sex couples, citing state laws that give registered domestic partners the same rights as spouses. Those laws provide such rights as child support and custody, joint property ownership, inheritance and hospital visitation, and access to divorce court.

But domestic partners are denied marital benefits under federal law, which means they can't file joint federal tax returns, collect Social Security survivors' benefits or sponsor one another as immigrants.

The suits before the court relied on the California Constitution, which state courts have long interpreted as being more protective of individual rights than the U.S. Constitution. The initiative that California voters are likely to consider in November would write a ban on same-sex marriage into the state Constitution, a step already taken by voters in half the states.

Gov. Arnold Schwarzenegger has twice vetoed same-sex marriage bills, citing a ballot initiative approved by more than 60 percent of the state's voters in 2000 that reaffirmed California's opposite-sex-only marriage law. That initiative was not a constitutional amendment, which requires more signatures to qualify for the ballot.

Suits similar to those that went before the California Supreme Court have been filed in other states, but only the Massachusetts Supreme Judicial Court has ruled that the state's constitution gives gay and lesbian couples the right to marry.

Courts in Vermont and New Jersey have found their states' marriage laws discriminatory but left the remedy up to state legislatures, which opted in both cases for civil unions for same-sex couples rather than marriage. A similar ruling by the Hawaii Supreme Court in 1993 was overturned by a ballot initiative.

The California case is In re Marriage Cases, S147999. The ruling is available at www.courtinfo.ca.gov/opinions.

Chronicle staff writers Cecilia M. Vega and Heather Knight contributed to this report. E-mail Bob Egelko at begelko@sfchronicle.com.

© 2008 The San Francisco Chronicle