WASHINGTON (AP) — President Barack Obama ordered his administration on Wednesday to stop defending the constitutionality of a federal law that bans recognition of gay marriage, a policy reversal that could have major implications for the rights and benefits of gay couples and reignite an emotional debate for the 2012 presidential campaign.

Obama is still “grappling” with his personal views on whether gays should be allowed to marry but has long opposed the federal law as unnecessary and unfair, said spokesman Jay Carney.

First word of the change came not from the White House but from the Justice Department. Attorney General Eric Holder announced that Obama had concluded the 15-year-old Defense of Marriage Act, or DOMA, was legally indefensible.

The decision was immediately welcomed by gay rights organizations and vilified by those on the other side. Some Democrats in Congress praised the decision, while it drew criticism from some Republicans and the office of their leader, House Speaker John Boehner, all surely a preview of coming political debate over the latest development in the long-running national conversation about gay rights.