(b)(7) EXEMPTION 7 (D) Identity of
a Confidential Source. This exemption provides protection for "records
or information compiled for law enforcement purposes [which] could reasonably
be expected to disclose the identity of a confidential source --including
a State, local, or foreign agency or authority or any private institution
which furnished information on a confidential basis--and, in the case of
a record or information compiled by a criminal law enforcement authority
in the course of a criminal investigation, or by an agency conducting a
lawful national security intelligence investigation, information furnished
by a confidential source."