Judge Candy Dale ruled in favor of four Idaho couples who sued the state over a 2006 constitutional amendment only recognizing marriages "between a man and a woman."
"The plaintiffs are entitled to extraordinary remedies because of their extraordinary injuries. Idaho's Marriage Laws withhold from them a profound and personal choice, one that most can take for granted," Dale said in her decision.
"By doing so, Idaho's Marriage Laws deny same-sex couples the economic, practical, emotional, and spiritual benefits of marriage, relegating each couple to a stigmatized, second-class status. Plaintiffs suffer these injuries not because they are unqualified to marry, start a family, or grow old together, but because of who they are and whom they love," she added.
Same-sex couples could marry in Idaho as soon as Friday morning, though Idaho Gov. Butch Otter vowed to appeal the ruling.
"In 2006, the people of Idaho exercised their fundamental right, reaffirming that marriage is the union of a man and a woman. Today's decision, while disappointing, is a small setback in a long-term battle that will end at the U.S. Supreme Court. I am firmly committed to upholding the will of the people and defending our Constitution," he said in a statement.
Deborah Ferguson, the plaintiffs' attorney, praised Dale's ruling, calling it "a victory not only for the courageous couples who brought this case, but for everyone who cares about freedom and fairness."