Advocates of same-sex marriage rights got a boost on Tuesday when a federal appeals court declared California’s gay marriage ban to be unconstitutional.

The voter-approved law, more commonly known as Proposition 8, was thrown out by a three-judge panel of the 9th US Circuit Court of Appeals. In a vote of 2-1, the panel said a lower court judge correctly interpreted the US Constitution and Supreme Court precedents by declaring in 2010 that Prop 8 was a violation of the civil rights of gays and lesbians.

“Although the Constitution permits communities to enact most laws they believe to be desirable,” the ruling states, “it requires that there be at least a legitimate reason for the passage of a law that treats different classes of people differently. There was no such reason that Proposition 8 could have been enacted.”

The news, however, is bittersweet. This doesn’t mean gay marriages can resume in the state immediately. The appeals court said that can’t happen until the deadline passes for Prop 8 sponsors to appeal to a larger panel of the 9th Circuit, and if such an appeal is filed, same-sex marriages cannot take place until the matter is resolved.

Backers of Prop 8 vowed to take the fight to the US Supreme Court. Brian Raum, senior counsel for the Alliance Defense Fund, a Christian legal aid group based in Arizona that helped defend Prop 8, said, “No court should presume to redefine marriage. No court should undercut the democratic process by taking the power to preserve marriage out of the hands of the people.”

But Santa Clara University constitutional law Professor Margaret M. Russell said the ruling overturned Prop 8 on “the narrowest grounds possible,’ which makes it less likely the Supreme Court would review it. Furthermore, Tuesday’s ruling was based on a 1996 Supreme Court decision that struck down a Colorado initiative preventing local governments from passing anti-discrimination ordinances to protect gays and lesbians.

The high court said then that the federal constitution prevents states from taking away rights from minorities because of moral disapproval.

Regardless of any future battles, American Foundation for Equal Rights President Chad Griffin called the panel’s ruling “a historic victory.”

“The message it sends to young LGBT people, not only here in California but across the country, [is] that you can’t strip away a fundamental right, and gay marriage is a fundamental right that no one can strip away,” Griffin said. “Now that Proposition 8 has been declared unconstitutional, the people of California will very soon be able to once again realize their freedom to marry.”

[The Seattle Times]