Doing that would have the effect of "throwing property rights into disarray, destroying the legal interests and expectations of thousands of couples and their families, and potentially undermining the ability of citizens to plan their lives according to the law as it has been determined by this state's highest court," the ruling said.
While gay rights advocates accused the court of failing to protect a minority group from the will of the majority, the justices said that the state's governing framework gives voters almost unfettered ability to change the California Constitution.
"We're relieved our marriage was not invalidated, but this is a hollow victory because there are so many that are not allowed to marry those they love," said Amber Weiss, 32, who was in the crowd at City Hall, near the courthouse, with her partner, Sharon Papo. They were married on the first day gay marriage was legal last year, June 17.
A small group of Proposition 8 supporters also gathered outside the court. "A lot of people just assume we're religious nuts. We're not. But we are Christians and we believe in the Bible," said George Popko, 22, a student at American River College in Sacramento, where the student government officially endorsed Proposition 8.
The state Supreme Court ruled 4-3 last May that it was unconstitutional to deny gay couples the right to wed. For a while, that put California — the nation's most populous state — back in its familiar position in the vanguard of social change; at the time, Massachusetts was the only other state to allow gay marriage.
In what gay activists called their "Summer of Love," same-sex couples from around the country rushed to get married in California for fear the voters would take away the right at the ballot box. In November, Proposition 8passed with 52 percent approval.
Over the past several months Iowa, Maine, Vermont and Connecticut legalized gay marriage, bringing to five the number of states that allow same-sex couples to wed.
In California, gay rights activists argued that the ban was improperly put to the voters and amounted to a revision — which required legislative approval — not an amendment. But the justices disagreed.
The court said that while the ban denies gay couples use of the term "marriage," it does not fundamentally disturb their basic right to "establish an officially recognized and protected family relationship with the person of one's choice and to raise children within the family." California still allows gay couples to form domestic partnerships.
In their 136-page majority ruling, the justices said it not their job to address whether the ban is wise public policy, but to decide whether it is constitutionally valid, while "setting aside our own personal beliefs and values."
Justice Carlos Moreno, who had been under consideration as President Barack Obama's nominee to the U.S. Supreme Court, was the lone dissenter. He said denying same-sex couples the right to wed "strikes at the core of the promise of equality that underlies our California Constitution." He said it represents a "drastic and far-reaching change."
"Promising equal treatment to some is fundamentally different from promising equal treatment for all," Moreno said. "Promising treatment that is almost equal is fundamentally different from ensuring truly equal treatment."
Today, California has lost its lead in the fight for civil rights for all people.