SAN FRANCISCO – A federal judge has ruled against California’s voter-approved marriage definition in a landmark decision that brings the gay marriage debate one step closer to the U.S. Supreme Court.

Nearly seven months after the battle over California’s Proposition 8 reached the U.S. District Court for the Northern District of California, Chief U.S. District Judge Vaughn R. Walker determined that people of the same sex do have the right to marry and that the decision of the majority to define marriage as the union between a man and a woman violates that right.

"Moral disapproval alone is an improper basis on which to deny rights to gay men and lesbians," the judge wrote in the 136-page ruling released Wednesday.

"The evidence shows conclusively that Proposition 8 enacts, without reason, a private moral view that same-sex couples are inferior to opposite sex couples," he added, effectively overturning Prop. 8.

With Walker’s ruling now out, the case will now head for the 9th U.S. Circuit Court of Appeals, which both sides in the legal battle had vowed to file an appeal to if Wednesday’s ruling was not in their favor. Prop. 8 defenders will ask the appeals court to immediately stay Walker's order.

The case, which has been followed closely by people on both sides of the marriage debate, could lead to a precedent for whether gay marriage becomes legal nationwide and – as traditional marriage advocates say – whether the nation’s democratic principles will be upheld.

If California’s Proposition 8 is overturned, marriage laws in 45 states and the federal Defense of Marriage Act may ultimately be nullified, law experts say.

Prop. 8, which California voters passed in 2008, effectively defined marriage in the state’s constitution as the union of one man and one woman. The amendment was passed by 52 percent of California voters.