By Jonathan Kaminsky
(Reuters) - Oregon will not defend a ban on gay marriage in the state, which was sued by four same-sex couples who argue the prohibition violates equality guarantees enshrined in the U.S. Constitution, the state's top law enforcement official said on Thursday.
The decision by Attorney General Ellen Rosenblum makes Oregon the third state in the past month to cease defense in federal court of gay marriage bans, after Nevada and Virginia, as activists fight for legalization across the United States.
"The law in this area is developing, and it is now clear that there is no rational basis for Oregon to refuse to honor the commitments made by same-sex couples in the same way it honors the commitments of opposite-sex couples," Rosenblum, a Democrat, said in announcing the decision.
But the move will not result in immediate legalization of gay marriage in the Democratic-dominated state, where a 2004 voter-approved amendment to the state constitution banned same-sex nuptials.
In all, 17 states and the District of Columbia recognize gay marriage in a trend that has gained momentum since the U.S. Supreme Court ruled in June that legally married same-sex couples nationwide are eligible for federal benefits. The court struck down part of the 1996 federal Defense of Marriage Act.
Since mid-December, federal judges have ruled prohibitions on same-sex marriage unconstitutional in Oklahoma, Utah and Virginia, although the decisions have been stayed pending appeal.
The New Mexico Supreme Court has also ruled gay marriage legal in that state, while in Colorado, nine couples filed suit in federal court on Wednesday to overturn that state's gay marriage ban.
While Oregon law bans same-sex marriages in the state, it does allow domestic partnerships and since October has recognized the marriages of same-sex couples wed elsewhere.
Oregon gay marriage backers had planned to put a repeal of the state ban before voters in November, but said they will hold the 160,000 signatures they have gathered pending the outcome of the court case.
"Now that we have done the hard work of assuring a place on the ballot and moving public opinion, we have the ability to wait for the courts to do the right thing," Oregon United for Marriage campaign manager Mike Marshall said in a statement.
Opponents of gay marriage said they were disappointed with the move, with the president of the National Organization for Marriage saying Rosenblum was "shamefully abandoning" her duty to defend an amendment enacted by voters.
"She swore an oath of office that she would enforce all the laws, not just those she personally agrees with," said Brian Brown, the organization's president.
With so many challenges to state gay marriage bans gaining traction in the lower courts, the U.S. Supreme Court may feel pressure to settle the question of whether gay couples have a constitutional right to wed, said Suzanne Goldberg, a Columbia Law School professor.
Should the Supreme Court take up the issue again, it will face a transformed political and legal terrain, Goldberg said.
"Whenever a case gets to the Supreme Court, the court will see a nation in which gay couples are marrying in many states and where some states no longer feel they can defend the exclusion of gay couples from marriage," Goldberg said. "That is a very different landscape from even a year ago."
(Reporting By Jonathan Kaminsky in Olympia, Washington; Writing by Cynthia Johnston; Editing by Amanda Kwan, Grant McCool and Andre Grenon)