From 9/11 Commission Report, 2004
In July 1995, Attorney General Reno issued formal procedures aimed at managing information sharing between Justice Department prosecutors and the FBI. They were developed in a working group led by the Justice Departments Executive Office of National Security, overseen by Deputy Attorney General Jamie Gorelick. These procedures - while requiring the sharing of intelligence information with prosecutors - regulated the manner in which such information could be shared from the intelligence side of the house to the criminal side.
These procedures were almost immediately misunderstood and misapplied. As a result, there was far less information sharing and coordination between the FBI and the Criminal Division in practice than was allowed under the departments procedures. Over time the procedures came to be referred to as the wall. The term the wall is misleading, however, because several factors led to a series of barriers to information sharing that developed.
The Office of Intelligence Policy and Review became the sole gatekeeper for passing information to the Criminal Division. Though Attorney General Renos procedures did not include such a provision, the Office assumed the role anyway, arguing that its position reflected the concerns of Judge Royce Lamberth, then chief judge of the Foreign Intelligence Surveillance Court. The Office threatened that if it could not regulate the flow of information to criminal prosecutors, it would no longer present the FBIs warrant requests to the FISA Court. The information flow withered.
SBD
Oh shit, I guess Bush won't get that third term after all...