A federal appeals court on Monday ordered the Obama administration to release a redacted version of secret memos justifying the use of drones to kill American citizens abroad.

The decision was hailed as a victory by civil liberties and media organizations who had sought access to the secret papers. The administration, under public pressure, has vowed to make changes to its lethal drone program but so far has resisted efforts to release documents on the legal justification for using drones to kill American citizens suspected of terrorism overseas.

The 2nd U.S. Circuit Court of Appeals in New York ruled that the administration must provide the redacted documents, because President Obama and senior government officials have commented on the subject.

Sen. Chuck Grassley, R-Iowa, who has also sought the legal rationale, called the ruling on Monday a "positive development."

"The targeted killing of American citizens by their own government should be one of the most fundamental reasons to ensure checks and balances are in place," Grassley said in a statement. "Up to this point, the Obama administration has been hiding behind a Cliff's Notes version of the justification that gave no legal analysis for the killings."

The 2nd U.S. Circuit Court of Appeals ruled in a Freedom of Information Act case brought by the American Civil Liberties Union and two reporters for The New York Times. In 2011, they sought any documents in which Department of Justice lawyers had discussed the highly classified "targeted-killing" program.

The requests came after a September 2011 drone strike in Yemen killed Anwar al-Awlaki, an Al Qaeda leader who had been born in the United States, and another U.S. citizen, Samir Khan, and after an October 2011 strike killed Abdulrahman al-Awlaki, al-Awlaki's teenage son and also a U.S. citizen. Some legal scholars and human rights activists complained that it was illegal for the U.S. to kill American citizens away from the battlefield without a trial.

In January 2013, U.S. District Court Judge Colleen McMahon ruled that she had no authority to order the documents disclosed, although she chided the Obama administration for refusing to release them.

But in an opinion written by 2nd Circuit Judge Jon Newman, a three-judge panel noted that after McMahon ruled, senior government officials spoke about the subject.

The panel rejected the government's claim that the court could not consider official disclosures made after McMahon's ruling, including a 16-page Justice Department white paper on the subject and public comments by Obama in May in which he acknowledged his role in the al-Awlaki killing, saying he had "authorized the strike that took him out."

Jameel Jaffer, deputy legal director of the American Civil Liberties Union, said in an email that "the government can't pretend that everything about its targeted killing program is a classified secret while senior officials selectively disclose information meant to paint the program in the most favorable light."

David E. McCraw, vice president and assistant general counsel of The New York Times Co., said in an email that the 2nd Circuit "reaffirmed a bedrock principle of democracy: The people do not have to accept blindly the government's assurances that it is operating within the bounds of the law. They get to see for themselves the legal justification that the government is working from."

The Associated Press contributed to this report.