It’s conventional wisdom that the legal “wall” between intelligence and law enforcement was one of the reasons we failed to prevent 9/11. The 9/11 Comission evaluated that claim, and published a classified report in 2004. The report was released, with a few redactions, over the summer: “Legal Barriers to Information Sharing: The Erection of a Wall Between Intelligence and Law Enforcement Investigations,” 9/11 Commission Staff Monograph by Barbara A. Grewe, Senior Counsel for Special Projects, August 20, 2004.

The report concludes otherwise:

“The information sharing failures in the summer of 2001 were not the result of legal barriers but of the failure of individuals to understand that the barriers did not apply to the facts at hand,” the 35-page monograph concludes. “Simply put, there was no legal reason why the information could not have been shared.”

The prevailing confusion was exacerbated by numerous complicating circumstances, the monograph explains. The Foreign Intelligence Surveillance Court was growing impatient with the FBI because of repeated errors in applications for surveillance. Justice Department officials were uncomfortable requesting intelligence surveillance of persons and facilities related to Osama bin Laden since there was already a criminal investigation against bin Laden underway, which normally would have preempted FISA surveillance. Officials were reluctant to turn to the FISA Court of Review for clarification of their concerns since one of the judges on the court had expressed doubts about the constitutionality of FISA in the first place. And so on. Although not mentioned in the monograph, it probably didn’t help that public interest critics in the 1990s (myself included) were accusing the FISA Court of serving as a “rubber stamp” and indiscriminately approving requests for intelligence surveillance.

In the end, the monograph implicitly suggests that if the law was not the problem, then changing the law may not be the solution.