A New Mexico county clerk on Wednesday began issuing marriage licenses to gay and lesbian couples in defiance of a state law.

Lynn Ellins, the county clerk for Dona Ana County, said that he based his decision to defy the law on a widely discussed legal opinion.

New Mexico is the only state in the country that neither recognizes nor prohibits the recognition of gay couples. The New Mexico Constitution's definition of marriage makes no mention of gender. But the state's application for a marriage license includes spaces to list the bride and the groom, terms Attorney General Gary King, a Democrat who is planning a bid for governor, has previously said are “gender specific.”

However, in a filing to a case challenging the state's marriage laws, King called the law unconstitutional.

“New Mexico's guarantee of equal protection to its citizens demands that same-sex couples be permitted to enjoy the benefits of marriage in the same way and to the same extent as other New Mexico citizens,” King's filing states.

Ellins echoed King's brief in announcing his decision.

“[I]t is clear that the state's marriage statutes are gender neutral and do not expressly prohibit Dona Ana County from issuing marriage licenses to same-gender couples,” Ellins said. “Any further denial of marriage licenses to these couples violates the United States and New Mexico Constitution and the New Mexico Human Rights Act. Dona Ana County is upholding New Mexico law by issuing these marriage licenses, and I see no reason to make committed couples in Dona Ana County wait another minute to marry.”

“We couldn't be happier for the couples in Dona Ana County – and those across the state who will soon, no doubt, make their way there – who have waited far too long for public sentiment and political courage to evolve far enough to publicly acknowledge their relationships as being just as equal as that of their neighbors,” Patrick Davis, executive director of ProgressNow New Mexico, said in a written statement.

Dona Ana County is the second county in the nation to begin issuing marriage licenses to gay couples in defiance of state law since the U.S. Supreme Court struck down the Defense of Marriage Act (DOMA), which prohibited the federal government from recognizing the legal marriages of gay couples.

Montgomery County, Pennsylvania has issued roughly 135 licenses to gay couples in the last month. The state has gone to court to stop the county from issuing additional licenses.

(Related: County official calls Pennsylvania's gay marriage ban “arbitrary.”)