SAN FRANCISCO (AP) – Two days of hearings over same-sex marriage in California concluded with a conservative group arguing that the state’s marriage laws do not discriminate against gays and lesbians because the institution’s purpose is to produce children.

“They can’t perform the basic functions of marriage, therefore it’s not discrimination,” Rena Lindevaldsen of the Campaign for California Families said Dec. 23, the second day of arguments in a high-profile case seeking to overturn the state’s ban on same-sex marriage.

But Sherri Sokeland Kaiser, arguing on behalf of the city of San Francisco, called the Lindevaldsen’s claims “extraordinary” and cited the state’s willingness to allow other people to marry who will likely never bear children, such as women over 50 and convicted criminals sentenced to life in prison.

She said marriage was a fundamental right to all Californians regardless of gender or sexual orientation. Current laws, she said, were discriminatory and based on sexual stereotypes.

“The state can’t dictate how we worship. The state can’t dictate our intimate associations, who we marry, whether we have children, how we conceive them and what we teach them,” Kaiser told San Francisco County Superior Court Judge Richard Kramer, who carefully followed each side’s arguments, interrupting occasionally with questions.

Judge Kramer has requested further written arguments by Jan. 14 and must issue a ruling within 90 days of that date.

A pair of lawsuits were brought by the city of San Francisco and attorneys for 12 same-sex couples. Together, the parties are attempting to make California the only state other than Massachusetts where same-sex couples can legally marry.

The state’s interest in raising children has formed the core of the arguments made by conservative groups seeking to maintain the state’s existing marriage laws. On Dec. 22, attorney Glen Lavy of the Alliance Defense Fund said the state should seek to promote families that include both a mother and a father as the ideal environment for raising children.

“The proponents are asking the court to destroy the cornerstone of a large building without considering the ramifications,” Lavy said. “If your honor finds the marriage laws must be available for same-sex couples, you will be likely creating a constitutional right to incestuous and group marriage.”

The following day, he said gays and lesbians aren’t discriminated against because many end up marrying people of the opposite gender.

“There is no suspect class of couples,” Lavy said. “Not all persons of gay or lesbian orientation are excluded from marriage … some of those people do marry.”

But same-sex marriage supporters shot down those claims.

“I guess they think the same-sex marriage we’re seeking won’t just be permitted, but required,” Kaiser said, eliciting chuckles from courtroom observers. “We’re here because we, like the plaintiffs, believe in the value of marriage and we want to protect our children, not steal away theirs.”

Lindevaldsen later accused the city of mocking her arguments.

The trial, which began Dec. 22, is limited to the issue of whether the California Constitution prohibits excluding same-sex couples from marriage.

Earlier, a lawyer for the 12 same-sex couples told a packed courtroom that California can no longer claim to have a legitimate reason for denying same-sex couples the right to marry given that such unions already are allowed in several places.

“The assertion that marriage is inherently heterosexual can no longer be maintained now that there are a number of jurisdictions that allow same-sex couples to marry,” said Shannon Minter of the National Center for Lesbian Rights, rattling off Massachusetts, Canada, Belgium and South Africa as among the places same-sex marriage is legal.

The trial is the first stop in what is expected to be a yearlong odyssey that could end in the state’s highest court. Kramer acknowledged as much.

“I want as clean a record and as prompt a resolution as possible because I’m fully aware I’m just the first stop,” he said. “I want all of these people sitting in the court of appeals as quickly as I can get them there.”

The consolidated cases were brought after the California Supreme Court ordered San Francisco officials to stop granting marriage licenses to same-sex couples. At that time, the court indicated it might be willing to consider the core constitutional issue after it passed through the lower courts.