A federal appeals court in Manhattan has struck down the Defense of Marriage Act, the law that defines marriage as only between a man and a woman.
In a 2-1 ruling, the 2nd Circuit Court of Appeals upheld a lower court's ruling that found the law violates equal protections rights.
Judge Chester Straub disagreed with the majority, saying the American people, not judges, should decide if the definition of marriage should be changed.
"Courts should not intervene where there is a robust political debate because doing so poisons the political well, imposing a destructive anti-majoritarian constitutional ruling on a vigorous debate," Straub wrote.
Traditional marriage supporters note that citizens in 32 states have voted to keep the definition of marriage as between one man and one woman.
Earlier this year a federal appeals court in Boston also found DOMA unconstitutional.
The fate of the law will most likely be decided by the U.S. Supreme Court.