U.S. District Judge Rosemary Collyer repeatedly expressed concern that the government's position would essentially strip U.S. citizens abroad of their constitutional rights. Deputy Assistant Attorney General Brian Hauck argued there was a difference between having a constitutional right—which he said could be protected by the executive and legislative branches—and being able to make constitutional claims in court. Collyer countered that not being able to access the courts would deprive citizens of the ability to enforce their rights.

The government argued the court should dismiss a lawsuit brought by the families of American citizens killed in Yemen in 2011 by targeted missile strikes. Justice Department lawyers argued the court was barred from hearing a case that would require an assessment of sensitive military and political issues far outside its purview and ability to review.

A Washington federal judge today said she was "troubled" by the U.S. Department of Justice's position that the courts are powerless to hear a challenge of the government's ability to target and kill U.S. citizens abroad.

"I'm really troubled…that you cannot explain to me where the end of it is," Collyer said. "That, yes, they have constitutional rights but there is no remedy for those constitutional rights."

The two missile strikes at issue killed suspected terrorist Anwar Al-Aulaqi, an American citizen, along with two other Americans, Al-Aulaqi's 16-year-old son Abdulrahman Al-Aulaqi and Samir Khan. In a complaint filed by the elder Al-Aulaqi's father and Khan's mother last July, they accused the federal government of violating the Americans' Fourth and Fifth Amendments rights.

Arguing before a standing-room only gallery, Hauck said the legal principle known as the political question doctrine prevented the court from taking up the case. A federal judge, he said, didn't have the same "apparatus" as the military and the executive and legislative branches to weigh the policy considerations that went into missile strikes. To consider a claim that the strikes were unconstitutional, Hauck said, the court would have to answer "extraordinarily sensitive questions."

When Hauck said that the "constitutional structure" enabled the executive and legislative branches to protect citizens' rights, Collyer pointed out that the structure included three branches of government.

"The problem is, how far does your argument take you?" Collyer said, adding that she found it "a little disconcerting" that the government was arguing that there could be no court review of a decision by the executive and Congress to target American citizens abroad.

Pardiss Kebriaei of the Center for Constitutional Rights, arguing for the plaintiffs, said the question of the whether the government violated the Americans' Fourth and Fifth Amendment rights could be answered by the court, pointing to a legal opinion published by the Justice Department spelling out the standards for deciding whether an attack was constitutional.

Collyer asked Kebriaei to explain how the court would evaluate some of the sensitive security questions at issue, such as whether an imminent threat justified the strikes. Kebriaei replied that that the court had taken up habeas petitions by detainees at Guantanamo Bay, which required the court to delve into national security issues.

The judge asked Hina Shamsi of the American Civil Liberties Union Foundation, also arguing for the plaintiffs, how the case could be brought under a 1971 Supreme Court ruling known as Bivens, which gave individuals the right to sue a federal official for alleged constitutional violations. The government argued that Bivens didn't apply because it would create a new category of cases that could be brought and raise separation-of-powers concerns.

Shamsi said it was a "quintessential Bivens case" because the plaintiffs had no other remedy. Unlike other terrorism cases cited by the government in which the courts found Bivens didn't apply, the current case didn't involve military operations during an immediate conflict and didn't raise questions of the plaintiffs' citizenship.

Collyer did not rule from the bench and didn't say when she expected to issue a decision.