SAN FRANCISCO (AP) -- Advocates on both sides of the gay marriage issue demonstrated outside California's highest court Thursday before justices heard arguments on lawsuits seeking to overturn the state's ban on same-sex nuptials.

Supporters of gay marriage carried rainbow flags and banners that urged the overturning of voter-approved Proposition 8, which took away the right of gay men and lesbians to wed.

Nearby, opponents of the unions held yellow signs left over from last year's campaign that said "Yes on 8." Others said, "A moral wrong cannot be a civil right."

Police officers stood watch, and while emotions ran high, the demonstration was peaceful.

Fewer than two dozen people who waited in line early Thursday were able to get a seats in the courtroom for the three-hour hearing. Gay rights groups also rented out a nearby auditorium and a big screen television for the outdoor plaza.

"It's important to show the Supreme Court justices history is on our side," said Paul Sousa, 22, of Boston, who flew to San Francisco on Wednesday to be close to the action. "Courts often can be a couple steps ahead of the curve on civil rights issues. We just have to help them get there."

The ballot initiative, which passed with 52 percent of the vote in November, changed the California Constitution to trump last year's 4-3 Supreme Court decision that held that denying same-sex couples the right to wed was an unconstitutional civil rights violation.

On Wednesday night, several thousand people marched from San Francisco's pro-gay Castro District to City Hall both to demonstrate public support for invalidating Proposition 8.

The Supreme Court's seven justices have 90 days after the oral arguments in which to issue a ruling.

"This is really about what the rest of the world sees - the rest of the world seeing there are huge numbers of people this issue touches," said Cherie Tony, 52, of San Francisco, who was among the crowd carrying candles and chanting "What do we want? Equal rights! When we do we want it? Now!"

Similar vigils were held in Los Angeles, other California cities, and as far away as New York. At the Los Angeles event, gay and lesbian couples decked out in wedding finery participated in a public "recommitment" ceremony.

Todd Barrett said he and his partner Joe Witmore, who were married during the 4 1/2-month window last year when same-sex couples could wed in California, brought their 5-year-old daughter to show that Proposition 8's passage affected families.

"I don't know how I would explain to her that Daddy and Pappa aren't married anymore," Barrett said.

The coalition of religious and conservative groups that sponsored the ballot initiative organized a statewide day of prayer on Sunday to rally support for upholding the measure and encouraged supporters to peacefully join same-sex marriage advocates outside the Supreme Court on Thursday.

"Our only purpose is to remind the media, Californians and Americans everywhere that support for traditional marriage is the majority position in the state," Ron Prentice, chairman of the ProtectMarriage coalition, said in a statement. "We won the Prop 8 election. The Constitution has been amended. The will of the people should now prevail."

Gay rights groups, couples and more than a dozen local governments are urging the court to overturn the measure on the grounds that it was put before voters improperly, or at least prematurely. Under state law, the Legislature must approve significant constitutional changes before they can go on the ballot.

Attorney General Jerry Brown has taken the unusual step of refusing to defend the gay marriage ban in court. His office argues that because the court has already recognized marriage as a fundamental right and gays as a minority group deserving of judicial protection, outlawing same-sex marriage is a constitutional breach.

Both Brown and the parties behind the lawsuits also claim that the ballot measure abrogates the court's role as the ultimate guardian of civil rights and if allowed to stand would leave other groups vulnerable to having their liberties curtailed.

The Supreme Court has asked the attorney general and lawyers for the couples, local governments and Proposition 8's sponsors to limit their arguments to three specific questions:

- Is Proposition 8 invalid because it constitutes a revision of, rather than an amendment to, the California Constitution?

- Does Proposition 8 violate the separation of powers doctrine under the California Constitution?

- If Proposition 8 is not unconstitutional, what is its effect, if any, on the marriages of same-sex couples performed before the adoption of Proposition 8?

Proposition 8's sponsors are being represented in court by former Pepperdine law school dean Kenneth Starr, who investigated President Bill Clinton during the Monica Lewinsky scandal. He argues that the ballot initiative was approved correctly and that it would be a miscarriage of justice for the court to overturn the results of a fair election.


Associated Press writer Raquel Dillon in Los Angeles contributed to this report.

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