WASHINGTON (CNS) — The Justice Department, in a brief filed Feb. 22 at the U.S. Supreme Court, said a federal law that defines marriage as between one man and a woman, denying financial benefits to legally wed same-sex couples, is unconstitutional.

“Moral opposition to homosexuality, though it may reflect deeply held personal views, is not a legitimate policy objective that can justify unequal treatment of gay and lesbian people” found in the 1986 Defense of Marriage Act, said the “amicus,” or friend-of-the-court brief, written by Solicitor General Donald Verrilli.

It was filed in the case of United States v. Windsor, for which the court will hear oral arguments March 27, a day after it hears oral arguments in another case weighing the constitutionality of same-sex marriage, Hollingsworth v. Perry. The second case is a challenge to California’s Proposition 8, a ballot initiative approved by voters in 2008 to ban same-sex marriage.

In the first case, Edith Windsor is suing over the Defense of Marriage Act because her same-sex marriage was recognized by the state of New York, but not by the federal government. Consequently, when her spouse died and she inherited her estate, Windsor had to pay $363,000 in federal estate taxes. Had her spouse been male, she would have been exempted from that tax.

The Defense of Marriage Act recognizes marriage as only between one man and one woman for the federal government’s purposes, such as for Social Security benefits, family medical leave and other federal programs, and federal estate and income taxes.

Last May, President Barack Obama said he now supported same-sex marriage, and later ordered the Justice Department not to defend the Defense of Marriage Act in court.

On Feb. 28, the Justice Department also filed a friend-of-the-court brief in the Proposition 8 case, urging the high court to strike down that law and laws in other states that have legalized same-sex civil unions, but not same-sex marriage.

The U.S. Conference of Catholic Bishops filed separate briefs in the two challenges facing the high court Jan. 29.

In the California case, the USCCB argues that although the Supreme Court “has held that laws forbidding private, consensual, homosexual conduct between adults lack a rational basis, it does not follow that the government has a constitutional duty to encourage or endorse such conduct. Thus, governments may legitimately decide to further the interests of opposite-sex unions only.”

The USCCB brief in the DOMA case says there is “no fundamental right to marry a person of the same sex. … Specifically, civil recognition of same-sex relationships is not deeply rooted in the nation’s history and tradition — quite the opposite is true.”

In a Feb. 20 interview with a San Francisco television station, Obama said, “I have to make sure that I’m not interjecting myself too much in this process, particularly when we’re not a party to the case.”

Archbishop Salvatore J. Cordileone of San Francisco, chairman of the U.S. bishops’ Subcommittee for the Promotion and Defense of Marriage, has called for renewed efforts to strengthen and protect traditional marriage.

“The meaning of marriage … cannot be redefined because it lies within our very nature,” he said. A concurrent issue in the Windsor case is whether House Republicans properly have standing to defend the Defense of Marriage Act.

On Feb. 22, attorneys for the lawmakers, calling themselves the Bipartisan Legal Advisory Group of the U.S. House of Representatives, said that it deserves standing, an assertion dismissed by the White House.

Meanwhile, The New York Times reported Feb. 26 that more than six dozen Republicans had signed their names to a brief to be filed with the high court outlining their support for same-sex marriage.