On July 16, 2001, the GAO sent Senator Fred Thompson a report he had requested as the Ranking Minority Member of the Senate Committee on Governmental Affairs. The report [pdf]
, FBI Intelligence Investigations: Coordination Within Justice on Counterintelligence Criminal Matters is Limited
(July 2001) (GAO-01-780), observed the following regarding the enactment of the Foreign Information Surveillance Act:
FISA was designed to strike a balance between the government's need for intelligence information to protect the national security and the protection of individual privacy rights...The Senate committee report provided that the basis for this legislation was the understanding that even if the President had an "inherent" constitutional power to authorize warrantless surveillance for foreign intelligence purposes, the Congress had the power to regulate the exercise of this authority by legislating a reasonable warrant procedure governing foreign intelligence surveillance. pg 6.
Thanks for requesting the report Fred.