Updated with response from CIA Director John Brennan at 11:33 a.m. ET
Senate Intelligence Committee Chairman Dianne Feinstein, D-Calif., on Tuesday went to the Senate floor to charge that the CIA was spying on committee staff members who were conducting oversight of the intelligence agency. The CIA's actions, which Feinstein said have serious "legal and constitutional implications," have been referred to the Justice Department.
"I have grave concerns that the CIA's search may well have violated the separation of powers principles," Feinstein said. The CIA's search of an isolated congressional computer system may have violated the Fourth Amendment, she said, along with laws such as the Computer Fraud and Abuse Act.
About an hour later at a Washington event, CIA Director John Brennan denied the allegation that the CIA improperly monitored Senate staff computers.
"Nothing could be further from the truth -- we wouldn't do that," Brennan said. "That's beyond the scope of reason."
"There is no legitimate reason to allege to the Justice Department that Senate staff may have committed a crime," Feinstein said. "I view the acting counsel general's referral as a potential effort to intimidate this staff, and I am not taking it lightly."
The controversy stems from the Senate Intelligence Committee's investigation into the CIA's now-defunct detention and interrogation program.
The report has yet to be declassified, but Feinstein said that the CIA's acting general counsel is mentioned more than 1,600 times in the report. He served as the lawyer in the CIA's counterterrorism center while the agency's detention and interrogation program was ongoing.
"Now this individual is sending a crimes report to the Department of Justice on the actions of congressional staff, the same congressional staff who... researched and drafted a report which details how CIA officers, including the acting general counsel himself, provided inaccurate information to the Department of Justice about the program," Feinstein said.
Feinstein noted that in 2009 she and then-CIA Director Leon Panetta agreed the CIA would provide the committee staff a "standalone computer system" with a "network drive segregated from CIA networks" for its investigation. Only information technology personnel for the CIA would be able to access the network -- no one else from the agency.
"It was this computer network that notwithstanding our agreement with Director Panetta was searched by the CIA," she said Tuesday.
The senator said she wrote a letter to CIA Director John Brennan on Jan. 17 objecting to any further CIA investigation on the grounds that it violated the separation of powers laid out in the Constitution. She sent a second letter on Jan. 23 asking Brennan 12 specific questions about the CIA's actions, such as the full scope of their search, the legal basis for it, and who authorized it.
"The CIA has not provided answers to any of my questions," Feinstein said, adding that she has limited information about what exactly the CIA did in conducting its search.
Brennan said Tuesday that the "appropriate authorities right now, both inside of the CIA and outside of CIA, are looking at what CIA officers and [Senate committee] officers did," adding that he will defer to those authorities as to whether anything inappropriate happened.Asked whether he would step down if something inappropriate did occur, Brennan said, "If I did something wrong, I will go the president... he is the one who can ask me to stay or to go."
Feinstein said she is aiming to have the committee report completed this month and approved for declassification.
"We're not going to stop," she said. "I intend to move to have the findings conclusions and the executive summary of the report sent to the president for declassification and release to the American people. The White House has indicated publicly and to me personally that it supports declassification and release."
The senator called this a "defining moment" for the Senate Intelligence Committee to reaffirm its oversight role and constitutional independence.
Other Senate leaders Tuesday commended Feinstein for speaking publicly about the controversy.
"Her remarks today outlined one of the most important principles we must maintain - separation of powers," Senate Majority Leader Harry Reid, D-Nev., said via Twitter.
Senate Judiciary Committee Chairman Patrick Leahy, D-Vt., said in a statement that Feinstein "described a troubling pattern of interference and intimidation by the CIA that raises serious questions about possible violations of the Constitution and our criminal laws."