A technical glitch gave the F.B.I. access to the e-mail messages from an entire computer network — perhaps hundreds of accounts or more — instead of simply the lone e-mail address that was approved by a secret intelligence court as part of a national security investigation, according to an internal report of the 2006 episode.
The 2006 episode was disclosed as part of a new batch of internal documents that the F.B.I. turned over to the Electronic Frontier Foundation, a nonprofit group in San Francisco that advocates for greater digital privacy protections, as part of a Freedom of Information Act lawsuit the group has brought. The group provided the documents on the 2006 episode to The New York Times.
Marcia Hofmann, a lawyer for the privacy foundation, said the episode raised troubling questions about the technical and policy controls that the F.B.I. had in place to guard against civil liberties abuses.
“How do we know what the F.B.I. does with all these documents when a problem like this comes up?” Ms. Hofmann asked.