The FBI's top lawyer said miscommunication - not malevolence - led the bureau in 2004 to improperly obtain the telephone records of newspaper reporters writing about Islamic terrorism in Indonesia.
Valerie E. Caproni, the FBI's general counsel, told The Washington Times in an interview that her explanation was based on a preliminary review of e-mails sent among agents at the time.
It was the first time an FBI official described any circumstances surrounding the situation, though the explanation seems unlikely to sway critics.
A more definitive account of the situation is expected to be included in a forthcoming report from the Justice Department's Inspector General (IG) into the use of so-called "exigent letters."
The FBI used such letters to request telephone toll-billing records and subscriber information, but not the content of the calls. The letters sent to the phone companies simply stated the information was being requested because of an emergency.
"Exigent letters" are similar to the controversial National Security Letters (NSLs), which allow agents to gather certain information without normal judicial oversight.
In the case regarding the New York Times and The Washington Post, the FBI violated a long-standing Justice Department policy that requires high-level approval before seeking that type of information from journalists.
FBI Director Robert S. Mueller III apologized to The Times and The Post earlier this month, and the case likely will be brought up Sept. 17, when he testifies before the Senate Judiciary Committee.
Ms. Caproni said the case agent e-mailed an agent in the terrorism-investigating Communications Analysis Unit (CAU) to suggest seeking Justice Department permission and a grand jury subpoena to obtain the reporters' phone records.
Ms. Caproni said the case agent did not say it was an emergency, but the agent in CAU sent an "exigent letter" anyway.
While it is not known why the agent in CAU sent the letter, Ms. Caproni suggested the agent in CAU may have been trying to be helpful. She also noted CAU is on the front lines of the fight against terrorism and that the unit was busy at the time.
Mike German, policy counsel for the American Civil Liberties Union's Washington legislative office, said he didn't buy Ms. Caproni's argument. "It's clear the FBI wants to minimize this as a mistake and not abuse," he said. "The facts are, there was a ridiculous amount of misuse and abuse."
Ms. Caproni said she does not want to minimize the bureau's mistakes, but stressed changes made in recent years should prevent a similar situation in the future.
She said the bureau has banned the use of "exigent letters" and has a new process in place to obtain such information in an emergency.
An agent seeking emergency toll-billing information from a phone company now must write a memo explaining the emergency that makes such a request necessary. Ms. Caproni said a supervisor must approve the request.
In the past, phone companies could refuse the requests made in an "exigent letter." But they were in a difficult position to do so because they didn't know the circumstances of the apparent emergency.
Now, Ms. Caproni said, the letters sent to phone companies must provide more facts to help the company determine whether the emergency is serious enough to turn over the records without first receiving a subpoena.
"This, at least, creates a factual record," Ms. Caproni said. "Assuming it passes the 'straight-face test,' we don't anticipate any problems with the phone companies."
According to a report from the Justice Department's inspector general, more than 700 "exigent letters" were sent from 2003 to 2006.
"The numbers of true emergencies is far smaller than that," Ms. Caproni said. "It's a small number of true emergencies, though there are some. There are times when we have true emergencies, and we need things quickly."
She said she is not sure how many letters have been sent under the new standards.
The upcoming IG report will be its third about the bureau's expanded investigative power under the Patriot Act, which originally was passed in response to the 2001 terrorist attacks.
The first two reports focused mostly on NSLs, which allow the bureau to act unilaterally in demanding financial, phone and other records. Unlike typical subpoenas or search warrants, NSLs do not need judicial approval.
The reports found widespread abuses.
"National Security Letters can be a valuable tool for the FBI to use in detecting and preventing acts of terrorism. But abuses should not be tolerated; there's too much at stake for the FBI to get it wrong," Sen. Charles E. Grassley, Iowa Republican and member of the Judiciary Committee, said Monday. "The FBI needs better transparency and accountability, and those who broke the rules should be held accountable."
Ms. Caproni said the biggest problems with NSLs were similar to those regarding "exigent letters" in the Times and the Post case. She described them not as malicious, but as "procedural" or "failure of care."
In 2007, the bureau increased training about NSLs and created a work-flow system that ensures supervisory review. Every NSL also must be reviewed by a bureau lawyer, she said.
Despite the changes, Ms. Caproni doesn't suspect any fewer NSLs are being sent.
Mr. German thinks the bureau's internal changes are not enough. "This requires outside oversight," he said. "Getting the courts involved is the most important check against abuses of executive power."