By Greg Miller,

After a conspicuous lull in the CIA drone campaign, the agency’s aircraft roared back to life in mid-March, 2011, with a multi-missile barrage near a remote village in Pakistan.

The strike at Datta Khel came one day after CIA contractor Raymond Davis was released from a Pakistani jail, and was quickly followed by reports that at least two dozen people — and perhaps as many as 44 — were killed.

Five years later, the true toll of that drone assault remains a mystery. A Taliban commander, Sherabat Khan Wazir, was reportedly among those killed. But the U.S. government has never explained who else died at Datta Khel, whether any of them were civilians, or how it made that determination.

The White House’s long-awaited release Friday of new details about the U.S. drone campaign did little to change that.

[Why CIA drone strikes have plummeted]

The newly released statistics help to delineate the overall dimensions of a drone program that grew from an experimental CIA platform designed to hunt Osama bin Laden into a clandestine air force carrying out hundreds of strikes from bases in at least nine countries on two continents.

But the White House offered scant insight into the targeting criteria used by the CIA and the U.S. military’s elite Joint Special Operations Command in making 473 strikes. Nor did it make a compelling case for why their casualty estimate of between 64 and 116 non-combatant civilians killed should be trusted, compared to far higher estimates compiled by independent groups.

[How U.S. Special Operations troops secretly help foreign forces target terrorists]

Letta Tayler, senior terrorism researcher at Human Rights Watch, led that organization’s efforts to examine seven U.S. strikes in Yemen between 2009 and 2013 that appeared to leave high numbers of civilian casualties. Unlike other estimates based largely on press reports, the group’s research involved visits to the sites of strikes and extensive interviews with witnesses, relatives and Yemeni officials. Overall, the organization concluded that at least 57 civilians, and possibly as many as 59, were killed in those seven strikes.

“I find it difficult to believe that in examining just seven attacks I happened upon well over half of the civilian deaths that the U.S. acknowledges,” Tayler said.

The strike that produced the highest number of civilian casualties came toward the end of Obama’s first year in office, when ship-launched cruise missiles carrying cluster munitions killed 14 suspected al-Qaeda fighters in Yemen but also as many as 41 civilians. According to Human Rights Watch, among them were 21 children and nine women.

[U.S. targets al-Qaeda in Yemen airstrike that kills dozens, Pentagon says]

The fallout from that U.S. attack put pressure on the White House to adopt stricter targeting guidelines and abandon the use of cruise missiles in counterterrorism operations. By 2013, Obama had imposed rules requiring evidence of an imminent threat to the United States and “near-certainty” that no civilians would be killed.

But a JSOC strike in December, 2013, on a train of vehicles leaving a wedding in Yemen exposed how even inside the U.S. government there could be intense disagreement over how to distinguish combatants from civilians.

The so-called “wedding strike” killed 12 people. JSOC concluded that all 12 were militants, according to U.S. officials briefed on the operation. But CIA analysts cast doubt on that claim, saying they could identify only one or two militants. The White House turned to the National Counterterrorism Center to referee the dispute, and its assessment concluded that as many as half of those killed were civilians.

This week’s release left unclear whether any of those killed in that operation were counted as civilians in the nearly eight-year total.

Even before the data release, the Obama administration has frequently depicted the drone campaign as almost unerringly precise. In 2011, near the peak of the drone war in Pakistan, Obama’s top counterterrorism adviser John O. Brennan — who now serves as CIA director — said that for nearly a year “there hasn’t been a single collateral death because of the exceptional proficiency, precision of the capabilities we’ve been able to develop.”

But those assertions have been undermined by the administration’s acknowledgment of grievous errors in recent years, including several that unintentionally killed U.S. citizens. Of the eight Americans killed in U.S. strikes, only one — Anwar al-Awlaki, a U.S.-born cleric who became a senior al-Qaeda operative in Yemen — was targeted and killed deliberately.

[Hostages’ deaths raise wider questions about drone strikes’ civilian toll]

One of those Americans, aid worker Warren Weinstein, was killed in a CIA drone strike on an al-Qaeda compound in Pakistan last year. Weinstein and an Italian citizen, Giovanni Lo Porto, had been kidnapped by al-Qaeda, but the agency was unaware that the two men were being held at the compound it targeted.

Former U.S. officials involved in overseeing the drone program said that at times even they were unsure about how the agency and JSOC categorized casualties. The confusion only deepened, they said as the administration ramped up its use of “signature strikes” in which targets are selected based on patterns of behavior seen as denoting terrorist activity even when the identities of those who would be killed is unknown.

As the drone war heated up in Obama’s first term, signature strikes came to account for more than two-thirds of the shots taken in Pakistan. A former senior U.S. official involved in overseeing the campaign said that in one briefing CIA officials argued that no civilians were left in the areas being patrolled by drones.

“Everybody who is in those zones is a combatant because everybody who is not a combatant has left,” the former official said. Like others, he spoke on condition of anonymity to discuss sensitive counterterrorism operations. The official said he and others pushed Obama to release more information on the drone program, but that intelligence agencies fought the proposals largely because they feared being drawn into a public fight over statistics.

“The main concern about putting out numbers was that people would ask for methodology — what is your test for distinguishing combatant and non-combatant?” the former official said. “The intelligence community] always said, ‘We’ll never get praise for [releasing drone data] so why do it?’”

Julie Tate contributed to this report.

Read more:

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