White House press secretary Jay Carney said Wednesday that Obama's "position on the Defense of Marriage Act has been consistent: He has long opposed it as unnecessary and unfair." He said that the president has been "grappling" with the broader issue of same-sex marriage.
Justice Department lawyers had appealed the decision of a federal judge in Massachusetts, who struck down the federal marriage law in July.
The new challenges to the Defense of Marriage Act that led to the administration's review were filed in November in federal courts in Connecticut and New York on behalf of same-sex married couples who say they were denied a variety of federal benefits.
In a statement and a letter to Boehner, Holder said the review focused on the legal standard that appellate courts should use in evaluating the law's constitutionality.
Unlike in Massachusetts, there has been little precedent in Connecticut and New York for how laws concerning sexual orientation should be reviewed.
That led the administration to change the legal approach it had followed in the past.
White House officials said the review that led to the decision was managed by White House counsel Bob Bauer, with input from senior adviser Valerie Jarrett, who oversees the office that conducts outreach to the gay community. Those officials were the subject of intense lobbying by gay rights groups who had opposed the administration's defense of the law, according to activists familiar with the White House's thinking.
While several Republicans issued scathing statements accusing the administration of shirking its responsibility to defend federal laws, as the Justice Department customarily does, they fell short of demanding that Congress step in.
In his letter to Boehner, Holder criticized portions of the congressional debate leading up to the law's passage, saying they had undermined the prospects for defending the measure. "The record contains numerous expressions reflecting moral disapproval of gays and lesbians and their intimate and family relationships - precisely the kind of stereotype-based thinking and animus that the Equal Protection Clause is designed to guard against,'' Holder wrote.
Staff writers Ed O'Keefe, Anne E. Kornblut and Perry Bacon Jr. and polling manager Peyton M. Craighill contributed to this report.