WASHINGTON -- In October 2011, Scott Shane, a national security reporter for The New York Times, sent an email to a branch of the Department of Justice that deals with Freedom of Information Act requests, to check on one of his FOIA filings.

Sixteen months earlier, Shane had asked that DOJ's Office of Legal Counsel -- which advises the White House on the legality of government actions -- release any memoranda it had relating to the president's top-secret program of targeted killing of suspected terrorists, much of which was understood to be conducted by drones.

President Barack Obama's drone and targeted killing program, which has remained highly obscure despite expanding rapidly under his watch, burst into the public discourse again on Monday after a DOJ briefing paper, outlining the executive branch's interpretation of its powers to kill extrajudicially, was published by NBC News.

But back in late 2011, the program, and its possible reach, was just starting to receive attention. That September, an American citizen named Anwar al-Awlaki, who had become a significant figure in al Qaeda in the Arab Peninsula, was killed in a CIA drone strike in Yemen. President Obama hailed the killing in a public address (see the video below).

A week later, Charles Savage, another national security reporter at the Times, wrote that Awlaki's killing -- and the killing, more broadly, of any American with close ties to al Qaeda -- had been authorized by a secret memo from the Office of Legal Counsel.

Shane pushed the Justice Department about his aging FOIA request. In June 2010, his request had been immediately accepted and granted "expedited processing," but now Shane wanted, as the OLC's FOIA officer later wrote to a colleague, "an explanation of why it had taken a year and a half to respond."

"We are almost finished processing his request," the colleague, OLC lawyer Peter Finn, wrote back.

A few days later, a response finally arrived in Shane's mailbox: Not only was the OLC denying his request, but it refused to acknowledge if the documents he'd requested even existed. "The very fact of the existence or nonexistence of such documents," the letter said, "is itself classified."

For the past three years, delays and convoluted explanations of this sort have been the response of the Obama administration to any effort to learn anything about the targeted killing program. For years, the government described any such program, and particularly the CIA's role in it, as so sensitive that it couldn't even be discussed. But long after the practice of targeted killing became a matter of widespread discussion -- and the president himself addressed targeting decisions in an informal Google hangout -- the administration has continued to use elaborate legal rationales and the blanket assertion of national security needs, to prevent any releases.

"To say that there is little transparency about the CIA's role in this is a real understatement," said Jameel Jaffer, a lawyer for the American Civil Liberties Union, which has had several FOIA requests denied on similar grounds. "We really have nothing at all, from the CIA itself, about its role, about the standards, about the process used to add people to kill lists, about number killed, about anything."

Every administration guards its secrets, but on his first day in the Oval Office, Obama promised to deliver a new era of government openness and ordered that FOIA requests be met quickly and generously.

Instead, the administration has thrown up roadblocks at every effort to learn about the targeted killing program. Court filings have been greeted with assertions of executive privilege or national security exemptions. Human rights researchers have been ignored. And at least a dozen formal inquiries from Congress have been met with silence.

FOIA experts have explored every avenue to squeeze out information. Jason Leopold, an investigative reporter with Truthout, has even asked for the emails behind the government's decisions to deny other FOIA filings. (It was one of Leopold's requests, shared with The Huffington Post, that revealed the OLC exchange about Shane.)

The administration's effort not to answer has been so convoluted and shrouded in obfuscation that one federal judge recently decried its "Alice-in-Wonderland nature," even as she concluded there was no way around the administration's arguments.

The lack of information affects not just legal watchdogs and government oversight; it also limits outside attempts to measure the efficacy of the program.

James Cavallaro, a human rights researcher at Stanford, recently spent six months attempting to meet with members of Obama's national security team before publishing a study that revealed the deadly consequences of the U.S. drone program in Pakistan. He never received a reply.

"It's disconcerting that there's not greater transparency and really unacceptable," Cavallaro said.

In his research on human rights violations around the world, Cavallaro noted that it's not uncommon for host countries to rebuff his requests for access and interviews (although he's had luck in some unlikely places, like Panama and Cambodia).

"But here's the kicker," he said. "Is that the standard that should apply in the United States? The standards of the many abusive governments that commit rights violations? If that's the standard the U.S. should hold itself to, then they're doing a fine job."

The ACLU had no better luck when it brought a lawsuit in mid-2010 against the government to prevent the killing of Awlaki, with his father as the plaintiff. The government responded in part that the case should be dismissed on the grounds that defending itself would require acknowledging a classified program. The case died a few months later.

But with every new speech by an administration official discussing the program, the blanket claim that the government cannot respond to FOIA requests or defend itself in court "becomes substantially less plausible," said Micah Zenko, an expert on targeted killing at the Council on Foreign Relations who has closely followed the secrecy debate.

"Every administration wants maximum power and minimum oversight," Zenko said. "Nobody wants to have their homework graded. But the whole point of the Constitution is that the president has his homework graded."

The Awlaki killing was the first known time an American citizen was deliberately killed by a U.S.-controlled drone strike. Two weeks later, his 16-year-old son, Abdulrahman al-Awlaki, was killed in a separate attack in Yemen. As Zenko has noted, administration officials initially claimed the boy was "in his mid-twenties" and "of military age," before being confronted with his true date of birth. The State Department still refuses to address the killing, saying that it has yet to receive proof of his death from Yemeni authorities.

The DOJ briefing paper published on Monday offers yet another twist in the saga. It is not the OLC memo on which Savage had reported in 2011, but is instead an unclassified summary of the memo that was given to Congress last summer.

But when a handful of journalists, learning about the existence of the paper last year, sent a FOIA request for a copy, they were told that it was just an unfinished part of the government's internal deliberation process. In other words, they were told it was a draft -- and not subject to FOIA release.

This story has been updated to note Truthout reporter Jason Leopold's work on uncovering the targeted killing program, including information he obtained from FOIA filings and shared with HuffPost.

Also on HuffPost:

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  • Lahore

    Pakistani NGOs workers shout slogans against US drone attacks and religious fundamentalism during a protest in Lahore on October 21, 2010. (Arif Ali/AFP/Getty Images)

  • Manila

    Protesters set on fire to a mock model of a U.S. drone during a rally near the U.S. Embassy in Manila, Philippines, on Friday Jan. 11, 2013. They protested an unarmed target drone found in central Philippine waters over the weekend which U.S. officials claimed was launched from a U.S. Navy ship during a combat exercise off Guam last year and may have been washed by ocean currents to the country. The embassy spokeswoman Bettina Malone said the BQM-74E drone was launched from the USS Chafee, a guided-missile destroyer, as a mock missile target during naval combat exercises off Guam. (AP Photo/Bullit Marquez)

  • Islamabad

    American anti-war coalition CodePink activists, protest while fasting to condemn U.S. drone attacks in Pakistani tribal region, Tuesday, Oct. 9, 2012 in Islamabad, Pakistan. The placard, center, reads, "fasting for peace." (AP Photo/B.K. Bangash)

  • New York

    Nick Mottern of Hastings-on-Hudson, N.Y., hands out information to a passerby as he stands beneath a model of an unmanned drone, which he labeled an "unmanned assasination vehicle" during an anti-war teach-in as part of the Occupy Wall Street protest now in its fourth week at Zuccotti Park in New York, Tuesday, Oct. 11, 2011. (AP Photo/Kathy Willens)

  • Washington DC

    A cardboard 'drone' is seen at an occupy DC camp in Freedom Plaza in Washington, DC. Occupy DC's website states the movement is built on the example of Occupy Wall Street, whose activists have continuously camped out in a New York park since September 17. (KAREN BLEIER/AFP/Getty Images)

  • Lahore

    Activists of the Pakistani fundamentalist Islamic party Jamaat-i-Islami (JI) shout slogans against the release of CIA contractor Raymond Davis and an US drone strike in the Pakistani tribal area, during a protest rally in Lahore on March 18, 2011. (Arif Ali/AFP/Getty Images)

  • Islamabad

    A Pakistani boy holds a placard during the second day of protests against the US drone attacks along with tribesmen of north Waziristan in Islamabad on December 10, 2010. (FAROOQ NAEEM/AFP/Getty Images)

  • Washington DC

    Members of Pax Christi USA, Foreign Policy in Focus, CODEPINK and other organizations, mock and protest the unmanned US drone attacks in Afghanistan and Pakistan on October 7, 2010 at Union Station in Washington DC. (KIMIHIRO HOSHINO/AFP/Getty Images)

  • Multan

    Pakistani demonstrators shout anti-US slogans during a protest in Multan on January 8, 2013, against the drone attacks in Pakistan's tribal areas. (S.S MIRZA/AFP/Getty Images)

  • Islamabad

    American citizens rally in Islamabad, Pakistan against drone attacks in Pakistani tribal belt, Friday, Oct. 5, 2012. (AP Photo/B.K. Bangash)

  • North Carolina

    Protesters march with a drone effigy outside Duke Energy headquarters in Uptown, the Charlotte the business district, before the start of the Democratic National Convention (DNC) September 2, 2012 in Charlotte, North Carolina. (Photo by Tom Pennington/Getty Images)

  • Florida

    Thomas Bolanos holds an American flag as he joins others in a protest in front of a Raytheon company building which they say is building military drones on August 23, 2012 in Largo, Florida. (Photo by Joe Raedle/Getty Images)

  • Florida

    Dina Formentini (C) and Code Pink leader Medea Benjamin (R) join others in a protest in front of a Raytheon company building which they say is building military drones on August 23, 2012 in Largo, Florida. (Photo by Joe Raedle/Getty Images)

  • Florida

    Code Pink leader Medea Benjamin holds a sign reading, 'Raytheon's Drones Create Enemies,' as she joins others in a protest in front of a Raytheon company building which they say is building military drones on August 23, 2012 in Largo, Florida. (Photo by Joe Raedle/Getty Images)

  • Florida

    Clay Colson holds a sign reading, ' Healthcare not Warfare!', as he joins others in a protest in front of a Raytheon company building which they say is building military drones on August 23, 2012 in Largo, Florida. (Photo by Joe Raedle/Getty Images)

  • Florida

    Code Pink leader Medea Benjamin holds a sign reading, 'Raytheon's Drones Create Enemies,' as she listens to a police officer ask the group to move to a public sidewalk durin a protest in front of a Raytheon company building which they say is building military drones on August 23, 2012 in Largo, Florida. (Photo by Joe Raedle/Getty Images)

  • Florida

    Liz, who only wanted to be identified by her first name, holds a sign reading, 'Obama's Drones Kill Americans, Too,' as she joins others in a protest in front of a Raytheon company building which they say is building military drones on August 23, 2012 in Largo, Florida. (Photo by Joe Raedle/Getty Images)

  • Florida

    James L. holds a sign reading, ' Obama is just another war prez ', as he joins others in a protest in front of a Raytheon company building which they say is building military drones on August 23, 2012 in Tampa, Florida. (Photo by Joe Raedle/Getty Images)

  • Philippines

    Protesters display placards during a rally near the U.S. Embassy in Manila, Philippines, on Friday Jan. 11, 2013. (AP Photo/Bullit Marquez)

  • Philippines

    Protesters march towards the U.S. Embassy in Manila with a mock model of a U.S. drone Friday Jan. 11, 2013. (AP Photo/Bullit Marquez)

  • YEMEN-UNREST-DEMO-DRONE

    Yemenis hold up a sign in Arabic that reads, 'No to Foreign Intervention...No to American Terrorism' during a protest against US drone attacks on Yemen close to the home of Yemeni President Abdrabuh Mansur Hadi, in the capital Sanaa, on January 28, 2013. Strikes by US drones in Yemen nearly tripled in 2012 compared to 2011, with 53 recorded against 18, according to the Washington-based think-tank New America Foundation. AFP PHOTO/STR (Photo credit should read -/AFP/Getty Images)

  • YEMEN-UNREST-DEMO-DRONE

    A Yemeni hold up a banner during a protest against US drone attacks on Yemen close to the home of Yemeni President Abdrabuh Mansur Hadi, in the capital Sanaa, on January 28, 2013. Strikes by US drones in Yemen nearly tripled in 2012 compared to 2011, with 53 recorded against 18, according to the Washington-based think-tank New America Foundation. AFP PHOTO/STR (Photo credit should read -/AFP/Getty Images)