The Obama administration recently announced that it would no longer defend a law barring the recognition of same-sex marriages, labeling the statute unconstitutional.

The unprecedented step may open the doors for gay marriage to be legalized nationwide.

U.S. Attorney General Eric Holder said in a Feb. 23 statement that the president and his advisors regularly review how they use the Justice Department to defend the U.S. Constitution. Holder said in this case, the President believes the law, Section 3 of the Defense of Marriage Act (DOMA), is in fact unconstitutional and will not engage in further legal defense of the measure.

“The Department has a longstanding practice of defending the constitutionality of duly-enacted statutes if reasonable arguments can be made in their defense,” Holder said in a statement. “At the same time, the Department in the past has declined to defend statutes despite the availability of professionally responsible arguments, in part because–as here –the Department does not consider every such argument to be a ‘reasonable’ one.”

Now, Holder said, with Section 3 of DOMA facing a challenge in the federal appeals court for the second circuit, “the Administration faces for the first time the question of whether laws regarding sexual orientation are subject to the more permissive standard of review or whether a more rigorous standard, under which laws targeting minority groups with a history of discrimination are viewed with suspicion by the courts, should apply.

“After careful consideration, including a review of my recommendation, the President has concluded that given a number of factors, including a documented history of discrimination, classifications based on sexual orientation should be subject to a more heightened standard of scrutiny,” Holder said.

Section 3 of the law, he said, fails to meet that and “is therefore unconstitutional.”

Coming on the heels of the announcement, the Maryland Senate passed the Civil Marriage Protection Act, a bill which would legalize same-sex marriage. The measure must still face an acrimonious battle in that state’s House of Delegates. However, the Human Rights Campaign applauded the Senate’s decision, saying the law would create better families and communities in the state.

“Today the state Senate recognized the simple truth that recognizing the love and commitment of same-sex couples under state law will strengthen families and communities,” HRC President Joe Solmonese said in statement. “This is a matter of fairness and equality and will put Maryland on the leading edge of giving loving same-sex couples the rights, responsibilities, benefits, and dignity that marriage entails, as have five other states and the District of Columbia.”

However, Sen. Rick Santorum (R-Pa.) called out Democrats and Republicans alike for not defending the Defense of Marriage Act.

“It is a reality that the media, not just the mainstream media but even quote-unquote conservative publications, like Fox—they tend to write rather negatively about people who stand up and fight for marriage,” Santorum told USA Today. “They describe it in terms of bigotry, in terms of discrimination, in terms of (being) homophobic.

“As a result of that, people stay away from it. They don’t want to be cast in that light by the media. And besides, we all have friends who are gay. I have friends who are gay. But they respect the fact that (I) disagree with them on policy.”

Despite Santorum’s comments, many civil rights groups say legalizing same-sex marriage won’t affect the sanctity of traditional marriages.

“When these couples join in marriage, their commitment will be strengthened, their families will share in the support and safety-net marriage brings, and it will take nothing away from anyone else,” said Evan Wolfson, founder and president of Freedom to Marry in a statement. “Stronger families mean a stronger community for everyone — a win-win in these tough economic times.”