"This is a failure of three systems," Clarke said. "It's a failure of the FBI background system, including polygraphs. It's a failure of the CIA hiring system, including polygraphs. And it's a failure of the FBI's computer system security, because she was able to obtain information that she shouldn't have had access to about Hezbollah, which she probably passed on to Hezbollah, a terrorist group."
As part of the investigation, the government is conducting a damage assessment. Officials told ABC News the amount of information they suspect was leaked appears to be limited, but investigators are checking all the ex-agent's contacts within both agencies and looking to see what databases she might have tapped into.
CIA spokesman Mark Mansfield issued a statement on the investigation, saying that the CIA cooperated with the investigation and that Prouty "was a midlevel employee who came to us in 2003 from the FBI where she had been a special agent. The naturalization issue occurred well before she was hired by the Bureau."
Mansfield confirmed that Prouty resigned from the CIA as part of her plea agreement.
"It is a sad day when one of our public servants breaches our security and trust," Assistant Attorney General Kenneth L. Wainstein said Tuesday. "This defendant engaged in a pattern of deceit to secure U.S. citizenship, to gain employment in the intelligence community, and to obtain and exploit her access to sensitive counterterrorism intelligence."
"It is fitting that she now stands to lose both her citizenship and her liberty," Wainstein added.
The plea agreement recommends that Prouty face a prison sentence between six and 12 months, and pay a maximum fine of $250,000. The documents also indicate Prouty will be on supervised release for two to three years after serving her sentence.