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SAN FRANCISCO, CA - DECEMBER 06: (L-R) Same sex couples and plaintiffs Sandy Stier, Kris Perry, Paul Katami and Jeffrey Zarrillo look on at a news conference following a hearing at the Ninth Circuit Court of Appeals on December 6, 2010 in San Francisco, California.

Two gay California couples who are leading the legal fight to overturn the state's ban on same-sex marriage said Thursday on the eve of their landmark Supreme Court hearing that they were relieved to have "the end in sight" and believe the justices will step in "to right these wrongs."

Kris Perry and Sandy Stier, and Paul Katami and Jeff Zarrillo, are the faces to the challenge to Proposition 8, a citizen's initiative denying gays and lesbians the right to wed that voters approved in a pitched multi-million dollar ballot battle in 2008. The court will hear arguments in the case on Tuesday.

“The right thing for the justices to do is to lead the country on including all of us in this institution and finding a way to equity and fairness that brings the country together rather than dividing us based on a characteristic that we cannot change,” Perry said on a call to reporters. 

Photo by Kevork Djansezian/Getty Images

Plaintiffs Kris Perry (L) kisses her partner Sandy Stier during a rally to celebrate the ruling to overturn Proposition 8 on August 4, 2010 in West Hollywood, California.

“There is an opportunity here for the court to send a message that who we love is important and we should be treated equally under the law," she added.

The couples will be in Washington, DC, for the historic hearing, which comes one day before the justices hear arguments contesting the constitutionality of a federal law, the Defense of Marriage Act (DOMA), that bars recognition of same-sex marriage and thereby denies more than 1,100 benefits to gay and lesbian couples. 

"We both are very relieved and excited by the prospect of the final chapter in this case happening in the next few months,” Perry said, adding that they have "been waiting a very long time to be married and to celebrate that with our children and our parents. … I know that we are both very excited to have the end in sight."

The couples' journey began years earlier, when they decided to join the legal effort and testified before lower courts about the impact the ban has had on their lives. They further entered the public realm as advocates, doing interviews and television/online spots about their campaign.

Photo by Kevork Djansezian/Getty Images

Lawyer Theodore Olson (L) and his clients Paul Katami (C) and his partner Jeff Zarrillo attend a rally to celebrate the ruling to overturn Proposition 8 on August 4, 2010 in West Hollywood, California. A federal judge overturned California's Proposition 8, a same-sex marriage ban, finding it unconstitutional.

“All four of us have regular lives and we have jobs that we need to pay our bills and so we have to be able to plug in and unplug when that happens,” said Zarrillo, of Burbank. “But being a part of this case, and being so closely associated with it, it reminds us of the daily harm and that discrimination even more every day.”

The legal struggle, he added, also “made us closer as a couple and has made us want access to that language even more, because the word 'marriage' and the word 'husband' and the word 'wife,' they have meaning” to society, family and children. 

“It affirms the commitment that we have built and shared,” he said. “While some people say it's just a word, that word is so important. And if it wasn't so important, we wouldn't even be having this conversation."

Stier, of Alameda, said being a part of the case has impacted their lives in a “dramatic way.” Two of the couple's four boys were headed to college when they joined the fight, but another two were just starting high school, and so that “experience has been happening in parallel with this case.”

“For Kris and I, the focus of our lives has always has been and continues to be our family,” said Stier. “And that will continue to be the driving focus of our lives and it's really what helps us be inspired by the case – is that we want other families to have the greatest potential for success.”

When the couples first joined the legal fight, the objective was to repeal Prop. 8, and lower courts sided with them. The latest court, the Ninth Circuit Court of Appeals, said that since same-sex marriage was allowed in California for a few months in 2008 before the vote, it could not be taken away.

The Supreme Court justices could agree with that lower court decision — in a move that would limit their ruling to couples in California — or they could side with the backers of Prop. 8. Efforts to reach the backers, ProtectMarriage.com, for comment on Thursday were not immediately successful.

The court also could broaden out their ruling to recognize same-sex marriage in all states, as the couples' attorneys have argued, saying that the more than 30 statewide bans on gays and lesbians getting married violate the U.S. Constitution. Nine state, plus the District of Columbia, allow same-sex marriage.

“If we've learned anything through this journey, it's that when the minority rights are being oppressed by a majority the court is supposed to step in, and some times it's not always popular for them to do so,” Zarrillo said. “We would expect the court to step in and right these wrongs."

As their legal battle seemingly winds down, Stier said the couples know that the journey they embarked upon is not their's alone but will affect many others, noting she felt they – and thousands more couples – were “on the cusp” of being able to finally legally wed.
 
“We are ... struck by the importance not only of being married but of a shift happening in the country that will affect generations to come,” she said. “When we imagine the day, we're standing somewhere and taking our vows and deciding to be married, we will not only be committing to each other but will be overwhelmed, I'm sure, by the power of this decision, not only for ourselves but for the whole country.”

Meanwhile, the opposition is gearing up for the fight — and is expecting a win. As Brian Brown, President of the National Organization for Marriage said in a statement:

"We, too, are looking forward to the court hearing. It represents the opportunity to right the wrong that was imposed by federal judges in stripping over 7 million California voters of their right to define marriage as the union of one man and one woman, the same definition that has guided civilization for thousands of years. We are confident of our position."

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Beck Diefenbach / Reuters file

Gay marriage supporters cheer during a rally moments before hearing that Proposition 8 had been overturned outside the Ninth Circuit Courthouse in San Francisco, Calif., on Feb. 7, 2012. A federal court later declined an appeal to revisit California's gay marriage ban in June, clearing the way for the Supreme Court to consider whether the ban violates the U.S. Constitution.

Gay rights groups cheered the Obama administration’s weighing in on a landmark Supreme Court case to allow same-sex marriage, while opponents decried the move as “war.”

But ultimately, constitutional and Supreme Court scholars say the government’s action of filing a legal brief on Thursday in support of repealing California’s Proposition 8, which bans gay marriage, will have little impact on the outcome of the case though it would carry some symbolic meaning.

Previous administrations have weighed in on cases brought to the nation’s highest court in which they were not directly involved -- such as the Truman and Eisenhower presidencies over the desegregation of schools, and the Reagan administration urging the justices to overrule the legalization of abortion, said Michael Klarman, a Harvard Law School professor and author of “From the Closet to the Altar: Courts, Backlash, and the Struggle for Same-Sex Marriage.”

“I don’t think that the government’s brief (on Prop. 8) would be that influential and I don’t say that because I think in general that’s the case, but I think everybody already knew what the administration’s position was,” he told NBC News.

“The president has made this such a salient issue and has been so clear about his position that I don’t think the brief really adds anything that we didn’t know,” he added, referring to Obama’s calls since last May for same-sex couples to have the right to marry, including his reference to the issue in his 2013 inaugural address.

Obama administration steps into gay marriage battle

The justices will hear oral arguments on Prop. 8 on March 26, with a decision expected in June.

In the legal filing, the Justice Department went further than the California case and suggested it was unconstitutional to block gay couples from getting married in at least seven other states where civil unions are offered instead. Those states, the department said, violate the Constitution if they offer civil unions to gay couples but deny them the right to marry.

While the administration takes no position in its brief beyond those states, its reasoning would have even broader implications. If the administration's legal theory were ultimately accepted, no state could, under constitutional guarantees against discrimination, deny same sex couples the right to marry.

But the administration is technically not a litigant to the Prop. 8 case, like it is in the other case that the justices will hear in late March over the constitutionality of the Defense of Marriage Act, a federal law barring recognition of same-sex couples.

G. Edward White, author of "The American Judicial Tradition: Profiles of Leading American Judges” and a Supreme Court scholar at the University of Virginia School of Law, said he thought the legal impact of the administration’s move in Prop. 8 would be “virtually zero.”

“I really don’t think one should attach any legal significance to this particular intervention,” he said before the brief was released.

Noting that Obama “been quite late to alter his view on same-sex marriage” -- he did so last May, announcing he supported it -- White thought this was a way to remind everybody that the administration “has now officially changed its mind on the issue.”

“My takeaway is really that this is a symbolic act on the part of the administration,” he said. “They’re doing it for political currency purposes. The justices are going to understand that’s what it is.”

William Eskridge, a professor at Yale Law School and a constitutional law expert who has authored many works on legal issues facing same-sex couples, said he didn’t think the brief would “necessarily change any minds” or be “as important for the outcome of the case” as the separate filings this week by about 130 notable Republicans as well as large businesses in support of same-sex marriage.

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Klarman, of Harvard, agreed, saying he thought the brief by the Republicans could influence Justice Anthony Kennedy, whom he considers the swing vote on gay marriage.

“I think someone like Justice Kennedy … is interested among other things in how much political backlash there would be to a ruling in favor of gay marriage. The fact that there's so many Republicans now committing to support it is highly relevant,” he said.

“I think it matters that Obama was re-elected," he also noted. "If there were a President Romney who would be committed to opposing the decision then I think, you know, a swing justice might be more hesitant. I think it matters that Obama is president and I think it matters that Obama already came out in favor of this, but I don’t think the brief really adds much information.”

Though the experts don’t expect the legal briefs to carry much weight among the justices, parties on both sides of the issue were roused by the move.

ProtectMarriage.com, which brought the legal challenge to keep Prop. 8 on the books after the state of California decided not to defend it, decried the effort, calling it a “frontal assault” on the law by the Solicitor General in an email to supporters.

The group also said the bid was “a stunning declaration of war against the longstanding meaning of marriage and its obvious ties to society’s interesting in both mothers and fathers raising the next generation.”

Meanwhile, the American Foundation for Equal Rights, the sole sponsor of the challenge to Prop. 8 that also organized the brief by moderate and conservative Republicans as well as Libertarians, welcomed the government to its side.

“The brief filed by the Solicitor General is a powerful statement that Proposition 8 cannot be squared with the principles of equality upon which this nation was founded,” the group said in a statement. “AFER looks forward to having Solicitor General (Donald) Verrilli and the federal government by our side as we make the case for marriage equality for all before the Supreme Court.”

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Actor and producer Clint Eastwood is seen in September 2012 in Westwood, Calif.

Clint Eastwood has joined about 130 self-described moderate and conservative Republicans in signing a brief to the Supreme Court arguing against California’s Proposition 8, which bans marriage for same-sex couples.

Former Bush administration officials, including Paul Wolfowitz, deputy secretary of Defense, and Tom Ridge, former Pennsylvania governor and Secretary of Homeland Security, also were among those who signed the brief, which argued that the Constitution prohibits denying same-sex couples access to the legal rights and responsibilities of marriage, according to a copy of the brief released Thursday by the American Foundation for Equal Rights.

Breitbart.com, which first reported that Eastwood had signed the brief, said he was a "long-time Republican with strong libertarian leanings," who had "become increasingly vocal politically." Eastwood's conversation with an empty chair representing President Barack Obama on the final day of the Republican convention briefly became a major topic on the campaign last fall.

The nation’s high court will hear arguments in the case on March 26. Thursday is the last day for briefs to be filed in the case, and officials told NBC's Pete Williams that the Justice Department will urge the court to approve gay marriage in California.

Six other former governors, including Jon Huntsman of Utah and Christine Todd Whitman of New Jersey, and ten former and two current members of Congress signed the brief, which was organized by AFER. Members of the George W. Bush, Mitt Romney and Sen. John McCain presidential campaigns also signed.

In the brief, the group said it was better for children to grow up with married parents, and that legalizing same-sex marriage would ease couples’ access to benefits and rights afforded to heterosexual couples but would pose “no credible threat to religious freedom or to the institution of religious marriage.”

They noted that many of those adding their names did not previously support same-sex marriage. But since a number of states have allowed gays and lesbians to wed, they, "like many Americans, have reexamined the evidence and their own positions and have concluded that there is no legitimate, fact-based reason for denying same-sex couples the same recognition in law that is available to opposite-sex couples."

Rather, they “concluded that marriage is strengthened, not undermined, and its benefits and importance to society as well as the support and stability it gives to children and families promoted, not undercut, by providing access to civil marriage for same-sex couples,” the brief continued.

Some on the list included who have had a change of heart on the issue include Meg Whitman, the Republican candidate for California governor in 2010, and David Frum, a special assistant to Bush from 2001 to 2002.

Once 'inconceivable,' Republican leaders sign pro-gay marriage brief

Numerous briefs have been filed in support of Prop. 8 by 20 states, religious groups, academics and legal scholars, as well as many against by businesses, labor unions, veterans, California plus thirteen states as well as the District of Columbia, and gay rights and religious groups.

National Football League players, Chris Kluwe, a punter for the Minnesota Vikings, and Bredon Ayanbadejo, a linebacker for the Baltimore Ravens, also filed a separate brief in the case that was released Thursday afternoon. The pair has been outspoken supporters of gay rights.

The California Supreme Court said in 2008 that the state had to allow same-sex marriage, and for a short period, some 18,000 same-sex couples wed in the Golden State. But with the passage of Prop. 8 later that same year, gays and lesbians were later prohibited from marrying. Various lower courts said the law was unconstitutional, with the most recent one determining such a fundamental right like marriage, that gays and lesbians had once enjoyed, could not be taken away.

The Supreme Court will also hear arguments in late March on Section 3 of the Defense of Marriage Act, which bars federal recognition of same-sex marriage. The Obama administration has encouraged the justices to strike down Section 3. In its argument, the administration noted that Proposition 8 and similar measures in other states were evidence that anti-gay discrimination remained a major problem.

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