WASHINGTON (RNS) The Obama administration announced on Wednesday (Feb. 23) it will no longer defend the Defense of Marriage Act, a nearly 15-year-old law that defines marriage as heterosexual unions.

In a letter to Congress, Attorney General Eric Holder said President Obama has determined the law, widely known as DOMA, is unconstitutional when applied to same-sex couples married legally under state law.

Holder, writing to House Speaker John Boehner, R-Ohio, said the decision came as he and the president reviewed the administration’s role in current court challenges from legally married same-sex couples in New York and Connecticut.

The attorney general said Obama considered a number of factors, including a history of discrimination against gays and a “growing scientific consensus” that a person’s sexual orientation cannot be changed.

In a statement, Holder noted the changing legal landscape since the law was passed, including Congress’ repeal of the military’s ban on openly gay members and the Supreme Court declaring aws criminalizing homosexual conduct are unconstitutional.

In a news briefing Wednesday, White House Press Secretary Jay Carney said the president has long considered DOMA “unnecessary and unfair” but the president is “grappling” with his views on gay marriage.

Family Research Council President Tony Perkins called the move “appalling” and urged Congress to defend DOMA.

Rea Carey, executive director of the National Gay and Lesbian Task Force, called the administration’s decision “ a tremendous step toward recognizing our common humanity.”