Twenty-six members of Congress have called on President Barack Obama to provide a legal justification for so-called “signature” drone strikes against suspected terrorists.

The Washington Post reported in April that the CIA and Joint Special Operations Command have been authorized to strike targets based solely on patterns of suspicious behavior that are detected through various means of intelligence — the actually identity of the target does not need to be known.

ADVERTISEMENT

“We are concerned that the use of such ‘signature’ strikes could raise the risk of killing innocent civilians or individuals who may have no relationship to attacks on the United States,” the members of Congress, lead by Rep. Dennis Kucinich (D-OH), wrote Wednesday in a letter to Obama. “Our drone campaigns already have virtually no transparency, accountability or oversight. We are further concerned about the legal grounds for such strikes under the 2001 Authorization for the Use of Military Force.”

“The implications of the use of drones for our national security are profound,” they added. “They are faceless ambassadors that cause civilian deaths, and are frequently the only direct contact with Americans that the targeted communities have. They can generate powerful and enduring anti-American sentiment.”

Before April, the CIA and JSOC were only authorized to use drone strikes against known terrorist leaders whose location could be confirmed.

Though the United States has been using drone strikes for years, the Obama administration did not publicly acknowledged that it was using drones in Yemen and Pakistan until May of this year. The New York Times later revealed the President was intimately involved in who was on the so-called kill or capture list. The Obama administration has also controversially defined “militants” as all military-age males in a given strike zone.