The Obama administration has taken another important step in its advocacy of same-sex marriage, weighing in on an important case to be heard in the US Supreme Court next month.

The essence of the administration’s argument is that the 1996 “Defense of Marriage Act” violates the US Constitution in defining marriage as the legal union between one man and one woman – specifically Section 3 of DOMA, which bars recognition of same-sex marriages in the granting of federal benefits including Social Security survivors’ benefits, immigration, insurance benefits for government employees, and filing joint tax returns.

In the Justice Department brief filed with the Supreme Court Friday, Solicitor General Donald Verrilli writes that DOMA’s Section 3 “targets the many gay and lesbian people legally married under state law for a harsh form of discrimination that bears no relation to their ability to contribute to society.”

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“It is abundantly clear that this discrimination does not substantially advance an interest in protecting marriage, or any other important interest,” Mr. Verrilli writes. “The statute simply cannot be reconciled with the Fifth Amendment’s guarantee of equal protection. The Constitution therefore requires that Section 3 be invalidated.”

The administration made it clear during the latter half of Mr. Obama’s first term that it would not continue to defend DOMA in the court cases where it’s been challenged. Taking up DOMA’s defense has been the “Bipartisan Legal Advisory Group” in the US House of Representatives, directed by Speaker John Boehner to take the place of the Justice Department in arguing court cases on behalf of the controversial law.

The House brief filed last month asserts that the same-sex marriage issue should be left to the democratic process and that gays are quite capable of pursuing their rights in those venues, according to a Politico analysis.

“Gays and lesbians are one of the most influential, best-connected, best-funded, and best-organized interest groups in modern politics, and have attained more legislative victories, political power, and popular favor in less time than virtually any other group in American history,” the House brief says.

Homosexual conduct has a history of being prosecuted as criminal in the United States. And although same-sex marriages now are legally recognized in nine states and the District of Columbia, many more states still have laws aimed at gays and lesbians – including restrictions on the adoption of children, banning gay marriage, and refusing legal benefits to same-sex couples.

“Tradition, no matter how long established, cannot by itself justify a discriminatory law under equal protection principles,” the Solicitor General writes in his brief.

The Supreme Court next month also is scheduled to take up California’s Proposition 8, which provides that "only marriage between a man and a woman is valid or recognized” in the state. Both Prop. 8 and DOMA have been declared unconstitutional by lower courts.

It’s unclear whether the Obama administration will weigh in against Prop. 8 as it has with DOMA.

“Next week I think we will see the government urging the same standard of review be used to overturn Prop. 8, and with it, all anti-gay-marriage laws,” Richard Socarides, a gay rights advocate and White House adviser to President Bill Clinton, told Politico. “It’s clear from the administration’s DOMA brief that they understand and now embrace its connection to the Prop. 8 case. The discrimination evidenced by Prop. 8 itself is cited to support the standard of review urged by the government to strike down DOMA.”

The DOMA case involves Edith Windsor, who lived with her partner Thea Spyer for many years. They were married in 2007 in Canada, returning to their home in New York where their marriage was recognized by state law. But when Ms. Spyer died in 2009, Ms. Windsor – because of DOMA – was forced to pay $363,000 in federal estate taxes that the surviving spouse in a heterosexual marriage would not have to pay.

As he has said, President Obama’s position on gay marriage has “evolved” in its favor.

In his inaugural address last month, he said, “Our journey is not complete until our gay brothers and sisters are treated like anyone else under the law – for if we are truly created equal, then surely the love we commit to one another must be equal as well."

Polls show a clear shift in public acceptance of same-sex marriage, especially among under-30 Americans – 63-35 percent approve, according to a Quinnipiac University poll in December. For all age groups, Gallup puts the number at 53-46 approval.

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