SAN FRANCISCO _-- California Supreme Court justices peppered lawyers arguing for and against same-sex marriage with tough questions for more than three hours Tuesday, the final public airing of the constitutional issues before the court hands down what could be a bellwether ruling for the nation.

At issue is whether marriage is a fundamental civil right only when it is between one man and one woman, or when it's between any two people. The court will rule within 90 days, almost certainly altering California's framing of the issue for decades to come; it wasn't clear Tuesday where the majority stands.

Several same-sex couples and advocacy groups joined by the city and county of San Francisco -- which ratcheted up the rhetoric by issuing same-sex marriage licenses in 2004, only to see them voided by this court -- argue California law's ban violates same-sex couples' equal-protection rights and has no rational purpose.

"You have to look at what's behind the tradition, what's the purpose of the tradition and does that purpose still make sense today," San Francisco Chief Deputy City Attorney Therese Stewart told the seven justices.

Associate Justice Carol Corrigan wondered whether the court should act while democracy runs its course through legislation and voter initiatives, but Shannon Minter, legal director for the National Center for Lesbian Rights, insisted "it's ultimately a constitutional question for this court to decide."

Later, questioned by Associate Justice Joyce Kennard, Minter argued same-sex couples' fundamental right to marry always has existed and only now is being recognized, just as racial and gender discrimination were only relatively recently recognized as unconstitutional. "It's that awakening where the evolution takes place," he said.

The state and two conservative groups contend there's no right to same-sex marriage, and that California's citizens and lawmakers should define marriage, not the courts.

The definition of marriage as between one man and one woman "has stood the test of time," said Christopher Krueger, California senior assistant attorney general, rejecting comparisons to a 1948 case in which the state Supreme Court deemed unconstitutional an interracial-marriage ban. Domestic partnership rights conferred under state laws enacted since this case began have eliminated the gap between same-sex couples and opposite-sex couples, he argued.

"Counsel, are you saying separate is equal here?" asked Associate Justice Carlos Moreno, referencing a standard the U.S. Supreme Court struck down in ending public-school segregation.

"These are separate institutions. ... There is equality," Krueger replied.

Attorney Kenneth Mennemeier, representing Gov. Arnold Schwarzenegger and the State Registrar of Vital Statistics, argued the interracial marriage ban was based on "very clear racial animus" explicitly forbidden by the state and federal constitutions. No such animus, and no such constitutional protections, apply to same-sex couples, he said.

Arguing against same-sex marriage in these six consolidated cases are the state Attorney General's office, which is duty-bound to defend existing state law; the conservative nonprofit Campaign for California Families; and the Proposition 22 Legal Defense and Education Fund, named for the 2000 ballot measure passed by 61 percent of voters to reinforce state law's pre-existing ban on same-sex marriage.

Arguing for the right to same-sex marriage are the city and county of San Francisco as well as a number of same-sex couples and gay-rights groups represented by a legal team led by the National Center for Lesbian Rights and including Lambda Legal, the American Civil Liberties Union, and several law firms.

San Francisco Superior Court Judge Richard Kramer in March 2005 found for same-sex marriage; the state Court of Appeals overturned his ruling with a 2-1 decision in October 2006; and the state Supreme Court unanimously agreed to review the case in December 2006.

"Words matter. Names matter," Stewart insisted Tuesday, later adding the title of marriage is a symbol conveying the public recognition of a private commitment. "That symbol has deep meaning for people on both sides of the case."

She conceded to Associate Justice Ming Chin that domestic partnership laws denote substantial progress toward equality but said "substantial progress is not equality." If the federal government and other states still won't recognize same-sex marriages, Chin replied, "doesn't that place rhetoric over reality?"

"I don't believe it does, your honor," Stewart answered. "People know what marriage means, it conveys a great deal. If the state says this is a marriage, it would be sending a message that California considers its gay and lesbian couples equal."

Chin asked whether the state can prohibit polygamy, underage marriage and incest. Minter agreed it can because it has legitimate, compelling interests in doing so, but no such interests exist to ban same-sex marriage. Questioned by Associate Justice Marvin Baxter, Minter said voters had no such rational purpose in approving Proposition 22.

Krueger said California's domestic partnership laws and others granting rights to same-sex couples, as well as New Jersey's enactment and study of a civil-unions system, show state legislatures are "a good place for that kind of policymaking decision." Marriage remains "a building block of our society" in which there's "a highly important governmental interest," he argued, "it's premature to rush ahead of the legislative process when that process is so fully engaged."

Glen Lavy, arguing for the Proposition 22 fund, said that ballot measure's passage means Californians don't believe public policy must embrace same-sex marriage and the court shouldn't redefine what marriage always has meant.

Kennard asked what adverse consequences same-sex marriage could have for California, and Liberty Counsel founder and president Mat Staver, attorney for the Campaign for Children and Families, replied "it would undermine opposite-sex marriage," depriving it of its meaning and benefits.

"I'm finding that argument a little elusive," Corrigan said.

"It would no longer be what it has historically been," Staver said. "It would lose its meaning."

As Stewart returned to the podium for a brief rebuttal, Chin asked whether Staver had just helped her case by acknowledging marriage has inherent value that domestic partnerships lack.

"I think he helped," she replied: Just as the court in 1948 didn't try to impose a system of "trans-racial unions" rather than striking down the interracial marriage ban, she said, nor should this court fail to recognize that the value of the institution of marriage itself is the bottom-line issue.

Offering apologies to William Shakespeare, Minter moments later said "same-sex couples have come here today to praise marriage, not to bury it."

"I thought when you invoked Shakespeare, you were going to ask, 'What's in a name?'" Chief Justice Ronald George said.

Reach Josh Richman at jrichman@bayareanewsgroup.com or 510-208-6428. Read the Political Blotter at http://www.ibabuzz.com/politics.