Republican Party senators opposed to the use of drones against American citizens have launched an effort to block a vote on U.S. President Barack Obama’s nominee to head the Central Intelligence Agency.
Rand Paul, senator from the state of Kentucky, launched the filibuster March 6 against John Brennan’s nomination to be CIA director.
Paul is demanding that the Obama administration issue a statement making clear that drones will not be used in the United States to kill terrorism suspects who are American citizens.
Senators were continuing to make filibuster speeches in the chamber late into the night.
Senators can speak for as long as possible, delaying action, until 60 votes in the 100-member Senate are gathered to end the filibuster.
In a letter to Paul this week, Attorney General Eric Holder said he could not rule out the use of drone strikes against American suspects on U.S. territory.
Holder said that while Obama had "no intention" to order such strikes, it theoretically could be possible if there was an "extraordinary circumstance," such as an attack similar to Pearl Harbor in World War II or the attacks of September 11, 2001.
The United States regularly uses missile strikes by the unmanned drone aircraft to target suspected terrorists, most notably in Pakistan, Afghanistan, and Yemen.
Critics say many civilians have been killed in such strikes, alongside militants.
In the United States, concerns have been raised following disclosures that the administration was reserving the right to target Americans suspected by high-ranking officials of plotting an imminent attack.
Defenders of civil liberties say such strikes could infringe on constitutionally protected due-process rights.
"I will speak until I can no longer speak," Paul said as he launched the filibuster around midday on March 6. "I will speak as long as it takes, until the alarm is sounded from coast to coast that our constitution is important, that your rights to trial by jury are precious, that no American should be killed by a drone, on American soil, without first being charged with a crime, without first being found guilty by a court."
Brennan earlier responded to a query from Paul, saying the CIA does not have the authority to conduct lethal operations inside the United States.
Brennan, considered a key architect of the drone program, is widely expected to eventually win a Senate majority to be confirmed as CIA chief.
Critics of the drone program point to the September 2011 strikes in Yemen that killed Muslim cleric Anwar al-Awlaki and Samir Khan – both U.S. citizens who had never been charged with a crime by U.S. authorities.
A drone strike two weeks later in Yemen killed Awlaki’s 16-year-old U.S.-born son.
Officials have said Awlaki was linked the planning of a series of attacks, including the attempted Christmas 2009 bombing of an airliner over Detroit.
The use of drone strikes began under the administration of President George W. Bush, but their frequency has increased since Obama took office in early 2009.
The record for longest U.S. Senate filibuster is held by the late Senator Strom Thurmond, who spoke for more than 24 hours against the Civil Rights Act of 1957.
With reporting by AP, Reuters, and dpa