July 2 (Bloomberg) -- Theodore Olson, the lawyer who won the 2000 Supreme Court case that made George W. Bush president, might have been the natural choice to argue in favor of California’s same-sex marriage ban.

“I said no, I did not want to do that, that I disagreed with Proposition 8 and would have voted against it,” Olson said, describing his response to proponents of the ban who approached him about defending it. “I have felt for a long time that we are not treating people who are gay or lesbian fairly.”

Instead, the lawyer associated with the Federalist Society, an organization of conservative attorneys in Washington, has lined up on the other side to sue the state in federal court. Almost as surprising is his co-counsel: David Boies, who opposed him in Bush v. Gore.

Olson, 68, who has argued 55 cases before the Supreme Court including as Bush’s solicitor general, has fought against causes such as affirmative action and campaign-finance regulation. Boies, 68, a Democrat, was named Lawyer of the Year by the National Law Journal in 1999 after taking on the antitrust case against Microsoft Corp.

The first hearing in their new case takes place today in San Francisco. Boies and Olson are arguing that the rights of gays and lesbians are the same enjoyed by all Americans.

“These individuals have a constitutional right to be married, just like the rest of us,” Olson said in an interview.

Legal Experts Split

Legal experts are split on the merits of the case and the likelihood of its success should it reach the Supreme Court. The court’s four more conservative members, Chief Justice John Roberts and Justices Antonin Scalia, Clarence Thomas and Samuel Alito, would reject same-sex marriage, said Dale Carpenter, a law professor at the University of Minnesota in Minneapolis.

On the other side, President Barack Obama’s choice to fill the seat of retiring Justice David Souter, appeals court Judge Sonia Sotomayor, has a scant record on the issue. And Justice Anthony Kennedy, the swing vote in many cases, is a question mark.

“It’s a roll of the dice, and potentially a high-stakes roll of the dice,” Carpenter said. “I still can’t count to five on the Supreme Court for gay marriage.”

In April, the Iowa Supreme Court struck down a same-sex marriage ban. Yet almost three-fourths of U.S. states have some sort of restriction, according to Lambda Legal, a gay-rights group in New York.

State Laws

Before Olson and Boies announced their case in May, gay- rights groups said that they should build support, counting on social change to generate new state laws.

The Olson and Boies case “poses a challenge at least in theory to the laws of more than 40 states,” said Jennifer Pizer, Lambda Legal’s national marriage project director. “Asking the Supreme Court and Justice Kennedy in particular to agree with that is a bigger ask than another way.”

As Olson and Boies promoted their case, groups including Lambda Legal released a statement that said, “the odds at the Supreme Court now are not so good,” adding that the high court had first ruled in favor of anti-sodomy laws and took 17 years to overturn its opinion.

Michael Dorf, a law professor at Cornell University in Ithaca, New York, said he would tell clients who wanted to pursue a federal challenge that if they failed, “this could make bad law for the nation and slow things down for everybody.”

Amicus Brief

Pizer and other gay-rights activists say they favor the strategy of change at the state level. However, they have embraced the Olson-Boies case, filing an amicus brief June 25.

“It’s different strategies toward a common goal,” said Pizer, 49, who married her wife last year.

Opponents of gay marriage are gearing up for the fight.

“The grassroots network continues to grow in response to what we may need,” said Ron Prentice, 52, executive director of protectmarriage.com, a coalition that helped pass Proposition 8, the ballot initiative defining marriage as between a man and a woman that passed in the Nov. 4 election.

The federal case was the brainchild of Chad Griffin, 35, a Democratic strategist. Griffin said he was dubious when an acquaintance suggested Olson as a prospective lawyer. “It seemed preposterous to me,” he said, referring to Olson’s association with conservative causes.

Yet he reached Olson and then met with him one-on-one in the lawyer’s Washington office on Nov. 21.

‘Effective Spokesperson’

Griffin said it then struck him “that perhaps I could be sitting across the office from someone who may become the most articulate, effective spokesperson for equality in gay marriage that our movement has ever seen.”

Olson suggested Griffin get Boies involved. The lawyers only knew each other slightly before Bush v. Gore and developed “a great deal of respect” for one another that morphed into friendship, Boies said in an interview.

Olson’s wife, Barbara, died the next year on the airplane that crashed into the Pentagon during the Sept. 11 attacks. When he remarried in 2006, the ceremony was attended by Boies and Justice Kennedy.

Boies said he and Olson now share dinners and bike trips. Last year, they toured Italy. The friends hadn’t talked about gay marriage, yet knew they shared “a view of the Constitution as being a critical document for protecting the rights of individuals,” Boies said.

Pro Bono

The lawyers are working partially pro bono; other costs are paid by the American Foundation for Equal Rights, a nonprofit set up by Griffin whose board members include Rob Reiner, the actor and director, and Bruce Cohen, who produced the film “Milk” about the assassinated gay-rights activist Harvey Milk.

Olson and Boies represent Kristin Perry and Sandra Stier, who have been together for nine years and have four children, and Paul Katami and Jeff Zarrillo, who have been together for eight years. Both couples have been unable to marry.

“This is a human-rights issue,” Boies said.

In court papers, the lawyers argued that gay people are being denied their rights under the Constitution’s due process and equal-protection clauses.

California currently allows domestic partnerships that have many of the same benefits as marriage. Yet the ban on marriage results in a “separate but unequal” status for gay people, Olson and Boies said in papers filed for the case, whose lead defendant is California Governor Arnold Schwarzenegger.

Colorado Case

In their briefs, the lawyers focused on two opinions written by Kennedy that supported gay rights. In one, a 1996 case, the court struck down a Colorado constitutional amendment that banned anti-discrimination protection for gay people.

In the second, a 2003 case, the Supreme Court overturned a Texas sodomy law and Kennedy wrote that gay people should have the same option as heterosexuals to pursue relationships. Scalia, in a dissent, said the court had “taken sides in the culture war” and cleared the way for same-sex marriage.

Olson and Boies also cited a 1967 case in which the court struck down a Virginia law that forbade blacks and whites from marrying each other. “Freedom to marry has long been recognized as one of the vital personal rights,” the court said.

The precedents mean there’s a “good chance” Olson and Boies could win in lower courts, said Douglas Kmiec, a constitutional law professor at Pepperdine University in Malibu, California. The case would then go to the Supreme Court, arriving with “bells, whistles, horns, sirens screaming ‘grant me,’” he said.

The case is Perry v. Schwarzenegger, 09-CV-2292.

To contact the reporter on this story: Kristin Jensen in Washington at kjensen@bloomberg.net

Last Updated: July 2, 2009 10:38 EDT