"Nobody has ever told me why my mother was targeted that day," he said through a translator. The schoolteacher got the chance to speak from an unusual source: U.S. Rep. Alan Grayson, the firebrand Democrat from Orlando, who brought him there to address the media and a few members of Congress.

Grayson is best known for the verbal grenades he tosses at U.S. conservatives. Last week, for example, he likened the tea party to the KKK. But he can be equally combative on issues of national security, even when his adversary is President Barack Obama, a fellow Democrat.

The approach has turned Grayson into a growing thorn in the side of the White House, especially on issues such as domestic surveillance and U.S. intervention in Syria, though administration officials have countered that Grayson is off base in some of his conclusions, including his stance against drones.

"We take extraordinary care to make sure that our counterterrorism actions are in accordance with all applicable domestic and international law and that they are consistent with U.S. values and policy," said Caitlin Hayden, a spokeswoman for the National Security Council, which advises the president on foreign policy.

These types of official assurances, however, haven't been enough for Grayson, who recently requested — and was denied — access to classified material related to the administration's proposal to attack Syria.

"My job is to make sure that you don't hear just one side of the argument," Grayson said. "In the case of the drone attacks, there is one side of the story that never gets told."

At Tuesday's briefing, the second-term lawmaker called on the administration to find an alternative to the strikes, which he referred to as "miniature acts of war."

Recent reports from the United Nations and human-rights groups assert that the U.S. has killed dozens, and possibly hundreds, of civilians in drone attacks, although specific figures are unavailable.

Administration officials would not speak directly to the 2012 incident in which Rehman said his mother was killed, but Hayden reiterated a point Obama has made before.

"To do nothing in the face of terrorist networks would invite far more civilian casualties — not just in our cities at home and our facilities abroad, but also in the very places where terrorists seek a foothold," she said.