WASHINGTON — Senators have dropped a demand for a public declaration of how many civilians the United States kills in CIA drone strikes each year after the US intelligence chief expressed concerns, congressional aides said.
The provision was included in Congress’ main intelligence bill for 2014, which passed a committee vote in November but has not been adopted by the full Senate.
President Obama tightened rules for drone attacks last year, partly to limit unintended casualties, and deaths have declined significantly. US officials say few civilians have died from drone attacks in Pakistan, Yemen, and elsewhere over the last decade, though unofficial tallies by human rights groups cite higher figures.
The government does not release casualty figures for drone strikes.
The New America Foundation, for example, maintains a database of the strikes using reports in major news media that rely on local officials and eyewitness accounts. It says at least 339 civilians died in Pakistan and Yemen, most after Obama became president in 2009. It labels a similar number of the dead as ‘‘unknown’’ — neither militants nor noncombatants.
Pakistan’s government told the United Nations last year the approximately 2,200 people killed by drones included 400 civilians.
Aides said the reporting requirement has been eliminated from the Senate bill. It is unclear when the legislation might be sent to the Senate for a vote.
‘‘The executive branch is currently exploring ways in which it can provide the American people more information about the United States’ use of force outside areas of active hostilities,’’ James Clapper, director of National Intelligence, wrote in a letter April 18 to Dianne Feinstein, Democrat of California, the Senate Intelligence Committee chairwoman.
He expressed reservations with the bill’s requirements.
‘‘To be meaningful to the public, any report including the information described above would require context and be drafted carefully so as to protect against the disclosure of intelligence sources and methods or other classified information,’’ Clapper said.
‘‘We are confident that we can find a reporting structure that provides the American people additional information to inform their understanding of important government operations to protect our nation, while preserving the ability to continue those operations.’’
Rights activists decried the change. ‘‘When it comes to killing people, the administration’s ‘trust us’ approach simply isn’t good enough,’’ said Zeke Johnson, director of Amnesty International USA’s security and human rights program.
‘‘Congress should be conducting vigorous oversight,’’ he said. ‘‘Years after Obama’s first strike, we’re still in the dark about basic information, including the number of people killed, their names, and the legal memos used to justify the killings.’’
A House bill compels Obama to do some of those things, though its support is uncertain.
The legislation proposed by Representives Adam Schiff, Democrat of California, and Walter Jones, Republican of North Carolina, would require Obama to produce an annual report with numbers of militants and civilians killed everywhere except in Afghanistan. The administration would have to provide figures dating back to 2009. Because the CIA drone program is covert, some have balked at public reporting requirements.