WASHINGTON — Engaging a high-ranking Obama administration official for the first time in an extensive public discussion of the use of drones for targeted killing on Thursday, senators pressed John O. Brennan, President Obama’s nominee for director of the CIA, about the secrecy of the strikes, their legal basis, and the reported backlash they have produced in Pakistan and Yemen.
Adding a new element to the roiling debate, the Senate Intelligence Committee’s chairwoman, Senator Dianne Feinstein, Democrat of California, said she would review proposals to create a new court to oversee targeted killings. She gave no details but said such a court would be analogous to the Foreign Intelligence Surveillance Court, which oversees eavesdropping on US soil.
Brennan was noncommittal, noting that lethal operations are generally the sole responsibility of the executive branch. But he said the administration had ‘‘wrestled with’’ the concept of such a court and called the idea ‘‘certainly worthy of discussion.’’
Brennan, 57, also faced intense questioning about whether he was responsible for leaks of classified information and about whether he has been candid about his involvement in the agency’s interrogation program under President George W. Bush.
But the senators repeatedly returned to the targeted killings Brennan has helped direct.
The hearing came three days after the leak of a Justice Department document explaining the legal rationale for the killing of US citizens who join Al Qaeda. On the eve of Brennan’s appearance, the White House gave into pressure from lawmakers and said members of the Senate and House Intelligence committees could see the full classified legal memorandum justifying the killing of Anwar al-Awlaki.
The US-born cleric joined Al Qaeda in Yemen and was killed in Yemen by a CIA drone strike in September 2011.
Feinstein expressed frustration at the committee’s difficulty in getting information about the targeted killing program. She said that while senators were allowed to view two legal memos, they were still seeking eight others, and committee staff members were still prohibited from reading the classified documents.
In his opening statement, Brennan acknowledged ‘‘widespread debate’’ about the administration’s counterterrorism operations but strongly defended them, saying that the United States remained ‘‘at war with Al Qaeda.’’
He said later that when CIA drone strikes accidentally kill civilians, those mistakes should be admitted.
“We need to acknowledge it publicly,’’ he said. ‘‘In the interests of transparency, I believe the United States government should acknowledge it.’’
But senators repeatedly complained that there is too little transparency about the targeted killing program, sometimes producing misleading information in the media.
“I think that this has gone about as far as it can go as a covert activity,’’ Feinstein told reporters after the hearing.
The hearing began in chaotic fashion, as protesters stood up and began shouting at Brennan before they were escorted out of the room. One man yelled, ‘‘Assassination is against the Constitution!’’ and one woman held up a sign that read: ‘‘Drones Fly Children Die.’’
The protests continued as Brennan began his opening statement. After the fifth interruption, Feinstein temporarily stopped the hearing and cleared the room, asking that activists from the peace group Code Pink not be readmitted.
When Brennan resumed his testimony, the top Republican on the committee, Senator Saxby Chambliss of Georgia, pressed him on his knowledge of the CIA’s previous use of brutal interrogation methods, which were adopted when Brennan was deputy to the agency’s number three official.
“I had some visibility into some of the activities there,’’ Brennan said. ‘‘But I was not a part of any type of management structure or aware of most of the details.’’ He said he opposed coercive methods and expressed objections privately to colleagues at the spy agency.