A federal appeals court on Tuesday declared California's same-sex marriage ban to be unconstitutional, putting the bitterly contested, voter-approved law on track for likely consideration by the U.S. Supreme Court.

A three-judge panel of the 9th U.S. Circuit Court of Appeals ruled 2-1 that a lower court judge correctly interpreted the U.S. Constitution and Supreme Court precedents when he declared in 2010 that Proposition 8 was a violation of the civil rights of gays and lesbians.