Updated: 3:15 p.m. EST

CINCINNATI — A federal judge Monday ordered Ohio authorities to recognize gay marriages on death certificates, saying the state’s ban on such unions is unconstitutional and that states cannot discriminate against same-sex couples simply because some voters don’t like homosexuality.

Although Judge Timothy Black’s ruling applies only to death certificates, his statements about Ohio’s gay-marriage ban are sweeping, unequivocal and expected to incite further litigation challenging the law.

Ohio’s attorney general said the state will appeal.

Black cited the Supreme Court’s June decision striking down part of a federal anti-gay marriage law, saying that the lower courts are now tasked with applying that ruling.

“And the question presented is whether a state can do what the federal government cannot – i.e., discriminate against same-sex couples … simply because the majority of the voters don’t like homosexuality (or at least didn’t in 2 004),” Black said in reference to the year Ohio’s gay marriage ban passed. “Under the Constitution of the United States, the answer is no.”

Eighteen states and the District of Columbia allow same-sex weddings, up from six before the Supreme Court decision.

Black wrote that “once you get married lawfully in one state, another state cannot summarily take your marriage away,” saying the right to remain married is recognized as a fundamental liberty in the U.S. Constitution.

“When a state effectively terminates the marriage of a same-sex couple married in another jurisdiction, it intrudes into the realm of private marital, family, and intimate relations specifically protected by the Supreme Court,” he wrote.

Black referenced Ohio’s historical practice of recognizing other out-of-state marriages even though they can’t legally be performed in Ohio, such as those involving cousins or minors.

Black’s decision stems from a lawsuit in July by two gay Ohio men whose spouses recently died and wanted to be recognized on their death certificates as married. The two couples got married over the summer in states that allow same-sex marriage.

Black said “there is absolutely no evidence that the state of Ohio or its citizens will be harmed” by his ruling but that without it, the harm would be severe for two men who filed the lawsuit because it would strip them of the dignity and recognition given to opposite-sex couples.

Black ordered the state not only to recognize the marriages of the two men who filed the lawsuit on their respective spouses’ death certificate but also to communicate his orders to anyone in the state involved in completing death certificates.

Attorney General Mike DeWine said the state will take its case to the 6th U.S. Circuit Court of Appeals, also based in Cincinnati. He called Monday’s decision “not a huge surprise,” given earlier rulings Black made in the case.

“Our job is to defend the Ohio Constitution and state statutes … and that’s what we intend to do,” DeWine said.

Bridget Coontz, the attorney who argued on behalf of the state, said Wednesday in court that in the Supreme Court’s historic June decision, the justices also found that states have the right to decide for themselves whether to recognize gay marriage, and Ohio voters decided not to in 2004.

“Ohio doesn’t want Delaware or Maryland to define who is married under Ohio law,” she said. “To allow that to happen would allow one state to set the marriage policy for all others.”

Civil rights attorney Al Gerhardstein argued to Black that the case was “about love surviving death” and said that the state had no right to recognize certain out-of-state marriages and not others.

Black sided with Gerhardstein, saying that constitutional rights trump Ohio’s gay marriage ban, questioning whether it was passed for a legitimate state interest “other than simply maintaining a ‘traditional’ definition of marriage.”

He quoted then-Gov. Robert Taft who said in 2004 that the law was intended “to reaffirm existing Ohio law with respect to our most basic, rooted, and time-honored institution: marriage between a man and a woman.”

Black wrote that “the fact that a form of discrimination has been ‘traditional’ is a reason to be more skeptical of its rationality.”

“No hypothetical justification can overcome the clear primary purpose and practical effect of the marriage bans … to disparage and demean the dignity of same-sex couples in the eyes of the state and the wider community,” Black wrote.

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