Judge Wood has served several stints in the executive branch, where her work focused on antitrust issues. But in a 2003 essay, she warned that steps proposed in the fight against terrorism, like diminishing privacy to facilitate executive surveillance, posed a threat to the rule of law.

“In a democracy, those responsible for national security (principally, of course, the executive branch) must do more than say ‘trust us, we know best’ when they are proposing significant intrusions on liberties protected by the Constitution,” she wrote.

And in a lecture about legal issues related to natural disasters, published in 2008, Judge Wood suggested that she would view trying terrorism suspects in military commissions, as Mr. Obama has proposed, with suspicion.