The Justice Department has released a long-secret legal document from 2001 in which the Bush administration claimed the military could search and seize terror suspects in the United States without warrants.
The legal memo was written about a month after the September 11 terror attacks. It says constitutional protections against unlawful search and seizure would not apply to terror suspects in the United States so long as the president or another high official had authorised the action.
Even after the Bush administration rescinded that legal analysis, the Justice Department refused to release its contents, which prompted a standoff with congressional Democrats.
The memo was among nine released on Monday by the Obama administration.
Another memo showed that, within two weeks of September 11, the administration was contemplating ways to use wiretaps without getting warrants.
The author of the search and seizure memo, John Yoo, did not immediately return a call seeking comment.
In that memo, Yoo wrote that the president could treat terror suspects in the United States like an invading foreign army. For instance, he said, the military would not have to get a warrant to storm a building to prevent terrorists from detonating a bomb.
Yoo also suggested that the government could put new restrictions on the press and speech, without spelling out what those might be.