Over the objections of its authors, the Department of Homeland Security classified a 2007 report from the National Academy of Sciences on the potential vulnerability of the U.S. electric power system until most of it was finally released yesterday.

The report generally concluded, as other reports have, that the electric grid is lacking in resilience and is susceptible to disruption not only from natural disasters but also from deliberate attack.

But even though the report was written for public release, the entire document was classified by DHS and could not be made available for public deliberation. Amazingly, it took five years for the classification decision to be reviewed and reversed. As Academy leaders explained in the Foreword to the report:

“DHS concluded that the report would be classified in its entirety under the original classification authority vested in the DHS undersecretary for science and technology. Because the committee believed that the report as submitted contained no restricted information, the NRC [National Research Council] requested the formal classification guidance constituting the basis for the classification decision. That guidance was not provided, and so in August 2010, the NRC submitted a formal request for an updated security classification review. Finally, in August 2012, the current full report was approved for public release, reversing the original classification decision, except that several pages of information deemed classified are available to readers who have the necessary security clearance.”

“We regret the long delay in approving this report for public release,” wrote Ralph J. Cicerone, president of the National Academy of Sciences, and Charles M. Vest, president of the National Academy of Engineering in the Foreword.

“We understand the need to safeguard security information that may need to remain classified,” they wrote. “But openness is also required to accelerate the progress with current technology and implementation of research and development of new technology to better protect the nation from terrorism and other threats.”

They said that a workshop was planned to address changes that have occurred since the report was completed in 2007.

See “Terrorism and the Electric Power Delivery System,” National Research Council, released November 14, 2012. (More from Foreign Policy, NYT)

Classification policy at the Department of Homeland Security has become somewhat more streamlined lately as a result of the Obama Administration’s Fundamental Classification Guidance Review.

Of the Department’s 74 security classification guides, 45 were revised and 16 were cancelled. Overall, 157 subtopics that had been classified — and that could be used to justify classification of DHS records — “were determined to no longer require classification,” according to the DHS final report on the Fundamental Classification Guidance Review of July 16, 2012.