SAN FRANCISCO (AP) – America’s debate over same-sex marriage took center stage Monday in a California courtroom at a closely watched federal trial that could ultimately become the landmark case that determines whether homosexual Americans have a right to marry.

The case will decide a challenge to the West Coast state’s ban on same-sex marriage that was approved by voters in 2008. The ruling probably will be appealed to the U.S. Supreme Court, and its ruling in the case could set precedent for whether same-sex marriage would become legal nationwide.

“This could be our Brown vs. Board of Education,” said former Clinton White House adviser Richard Socarides, referring to the 1954 Supreme Court decision that outlawed racial segregation in U.S. public schools. “Certainly the plaintiffs will tell you they are hoping for a broad ruling that says that any law that treats someone differently because of sexual orientation violates the U.S. Constitution.”

The case marks the first federal trial to examine whether the U.S. Constitution allows the banning of marriages between couples of the same sex, and the challenge is being bankrolled by a group of liberal Hollywood activists led by director Rob Reiner.

They retained two of the nation’s most influential lawyers to argue the case – former U.S. Solicitor General Theodore Olson and trial lawyer David Boies. The lawyers are best known as the rivals who represented George W. Bush and Al Gore in the dispute over the 2000 presidential election in Florida, in which the justices’ order ended recounts and gave the presidency to Bush.

California’s Republican Gov. Arnold Schwarzenegger and Democratic Attorney General Jerry Brown are defendants in the lawsuit by virtue of their prominent positions in California government, but both opposed the ban and have refused to defend the suit in court. Schwarzenegger has taken no position on the case, while Brown filed a brief saying he agreed with the Olson-Boies team that gays have the same federal constitutional right to marry as heterosexuals.

The sponsors of the same-sex marriage ban, a coalition of religious and conservative groups, joined the case as defendants. Their legal team is being led by Charles Cooper, a veteran trial lawyer who worked for the U.S. Justice Department under Republican President Ronald Reagan in the 1980s. Cooper is being assisted by a team of lawyers from his own firm, along with a Christian legal group based in Arizona.

Presiding over the case is U.S. District Court Chief Judge Vaughn Walker, a Republican named to the bench in 1989 by Bush’s father, President George H.W. Bush. Walker, who has a reputation as an independent thinker, was randomly assigned the lawsuit, put it on a fast-track to trial and has said he thinks it raises serious civil rights claims. During a pretrial hearing in August, the judge pointedly scolded Schwarzenegger for remaining neutral “on an issue of this magnitude and importance.”

Walker says the case is so important that the court has taken the rare step of allowing videotaping of the proceedings so the public can watch. The trial, scheduled to start Monday, will air on YouTube every day.

To prevail, Olson and Boies will try to prove that denying homosexuals the right to wed serves no legitimate public purpose and that Proposition 8 was motivated by legally irrelevant religious or moral beliefs or even anti-gay bias. The ballot initiative, which passed with 52 percent of the vote, supplanted a California Supreme Court ruling that had legalized same-sex marriages.

Boies and Olson say the ban is a blatant violation of constitutional rights to equal protection and due process.

Testimony in the trial will explore many of the most contentious political arguments surrounding the issue. Leaders of the campaign to outlaw gay marriages have been called as witnesses, along with competing academic experts who will be cross-examined on topics ranging from how having same-sex parents affects children and if gay unions undermine male-female marriages.

Cooper’s team plans to argue that same-sex marriage is a social experiment and is therefore prudent for states like California to take a wait-and-see approach. Their witnesses will testify that governments historically have sanctioned traditional marriage as a way to promote responsible child-rearing and that this remains a valid justification for limiting marriage to a man and a woman.

“What sets this case apart is the strategy up until now, in the last 10 or 15 years, has been by the national organizations that support same-sex marriage to attack this on a state-by-state basis,” said Brian Raum, who is helping to defend Proposition 8. “The impact of those cases, obviously, was limited to their respective states. But the potential impact in this case goes beyond the state of California.”

Kristin Perry, 45, is the title plaintiff in the case registered on legal dockets as Perry v. Schwarzenegger. She and her lesbian partner of 10 years, Sandra Stier, 47, were married in San Francisco in 2004 when Mayor Gavin Newsom ordered city officials to issue marriage licenses to same-sex couples. Six months later, they were among the 4,000 couples who had their unions invalidated by the state Supreme Court.

Perry and Stier, who have four sons, agreed to become involved in the challenge because they believe that a judicial approach grounded in constitutional law provides the best chance of success. Still, many gay rights advocates objected to the timing of the lawsuit, fearing it was too soon to mount a federal case.

“All the other experiences around this have felt so politicized and in some ways outside of my control,” Perry said. “But being in a courtroom where the rules of discussion are so different from a political discussion, I am feeling like as an American I have a right to ask someone if this is fair, someone whose job it is to do this every day and can make as educated a judgment about this as maybe anyone has made.”

The plaintiffs will have plenty of star power with Olson and Boies. Olson helped Bush win the presidency in 2000 after the recount battle in Florida, and later served as the president’s solicitor general, the lawyer who argues the government’s cases before the Supreme Court. Boies represented Gore in 2000.

“The hope of the people behind this, in recruiting Olson and Boies, was to put a bipartisan face on this issue,” said Jane Schacter, a constitutional law expert at Stanford University in California. “I do think it’s striking that one of the nation’s senior conservative litigators is leading the charge, and it does cause some people maybe to take a second look, to see the issue through a different prism.”