WASHINGTON — Mary O. McCarthy, the intelligence officer dismissed Friday after being accused of leaking information to reporters about the Central Intelligence Agency's overseas prisons, once was responsible for guarding some of the nation's most sensitive secrets.
As a senior National Security Council aide for intelligence from 1996 to 2001, McCarthy was known as a low-key professional who paid special attention to preventing White House leaks of classified information and covert operations, several current and former government officials said.
When she disagreed with decisions on intelligence operations, they say, she registered her complaints through internal government channels.
But on Thursday she was stripped of her security clearance and escorted out of CIA headquarters, government officials said, after failing a polygraph examination and confessing that she had disclosed classified information to reporters, including material for The Washington Post's Pulitzer Prize-winning articles about secret CIA facilities in Eastern Europe used to interrogate captured al-Qaida members and other terror suspects.
McCarthy, who has not been charged with any crime, did not respond to telephone calls and an e-mail message. But former colleagues who worked with her at the CIA and the White House say they had trouble fathoming her as a source of the leaks. Some said they flatly refused to believe the accusations.
"We're talking about a person with great integrity who played by the book and, as far as I know, never deviated from the rules," said Steven Simon, a National Security Council aide in the Clinton administration who worked closely with McCarthy, who is in her early 60s.
"I have no idea what her motive was, but there is a lot of dissension within the agency and it seems to be a rather unhappy place," said Richard J. Kerr, a former CIA deputy director. Kerr called McCarthy "quite a good, substantive person on the issues I dealt with her on."
After an article last November in The Washington Post reported that the CIA was sending terror suspects to clandestine detention centers in several countries, including some in Eastern Europe, Porter J. Goss, the agency's director, ordered polygraphs for intelligence officers who knew about certain "compartmented" programs, including the secret detention centers for terror suspects.
But some former CIA employees who know McCarthy remain unconvinced, arguing that the pressure from Goss and others in the Bush administration to plug leaks may have led the agency to focus on an employee on the verge of retirement, whose work at the White House during the Clinton administration had long raised suspicions within the current administration.
"It looks to me like Mary is being used as a sacrificial lamb," said Larry Johnson, a former CIA officer who worked for McCarthy in the agency's Latin America section.