The first federal case to challenge the constitutionality of a gay marriage ban began with emotional testimony in San Francisco Monday.

Ted Olson, lawyer for the plaintiffs, a gay and a lesbian couple who have been denied the right to marry in California because of Proposition 8, the gay marriage ban approved by voters in 2008, described marriage as “a basic civil right” in his opening statement.

“As the witnesses in this case will elaborate, marriage is central to life in America. It promotes mental, physical and emotional health and the economic strength and stability of those who enter into a marital union,” he said.

“Proposition 8 ended the dream of marriage, the most important relation in life, for the plaintiffs and hundreds of thousands of Californians.”

“Proponents of Proposition 8 have insisted that the persons they would foreclose from the institution of marriage have suffered no harm because they have been given the opportunity to form something called a 'domestic partnership'.”

“That is a cruel fiction,” he added.

Outside the courtroom, activists gathered. About a dozen proponents of Proposition 8 were greatly outnumbered by gay marriage supporters, who chanted, held signs and sang songs.

First to take the stand was Jeffrey Zarrillo, 36, who testified he wants to marry his partner of nearly nine years, Paul Katami.

“He is the love of my life. I love him probably more than I love myself. I would do anything for him,” Zarrillo said as he held back tears.

Zarrillo said a domestic partnership made him a third class citizen: “It's giving me part of the pie, but not the whole thing.”

Zarrillo's partner, Paul Katami, 37, testified that marriage would allow “us access to the language. Being able to call him my husband is so definitive … We both dislike 'lover'.”

Chief U.S. District Judge Vaughn Walker announced at the start of the trial that the Supreme Court was reviewing an application submitted by proponents of Proposition 8 that prevents broadcast of the proceedings. The high court said it would make a final ruling on Wednesday. Walker called the development “highly unfortunate.”

Sandra Stiers, 47, testified she was married to a man for 12 years without knowing she was a lesbian.

“At that time I did not know I was a lesbian. I had a difficult relationship, but it started with the best intentions. Divorced 1999,” she said.

“I met Chris [Perry] in 1996. I was teaching a computer class and she was a student in my class. We later became coworkers and fast friends. I began to realize my feelings for her were unique, and taking over my thoughts. I was falling in love with her. I realized this in 1999. My marriage was troubled on many fronts. The end of my marriage was precipitated by my unhappiness and my husband's alcoholism. My sexual orientation had nothing to do with the divorce.”

“I want to marry Sandy [Stiers],” Perry answered to the question, “Why are you a plaintiff in this case?”

“I want the discrimination to end and a more joyful part of our life to begin. Growing up as a lesbian you never let yourself want it because everyone tells you you can't have it. I think what it means is your relationship is honored. People know what your relationship is. The state isn't letting me feel happy. The state isn't allowing me to feel my whole potential.”

Lawyers arguing in support of Proposition 8 said monogamous heterosexual marriage was universally accepted. But Harvard professor Nancy Cott, an expert in the history of marriage in the United States, disagreed, testifying ancient Jews were polygamous.

The trial continues Tuesday and is expected to last 3 weeks.