Last December an intelligence historian named Matthew Aid was doing research at the National Archives when he noticed that documents he had copied years before, including State Department reports from the Korean War era, had mysteriously vanished. Other historians had observed the same phenomenon: Innocuous material they had in their own files had been reclassified and withdrawn from public access.
In response to complaints from Aid and others, the National Archives conducted an audit of more than 25,000 publicly available documents that had been reclassified since 1995 by agencies such as the CIA, the Air Force, and the Energy Department. According to the resulting report, released in late April, 24 percent of the reclassification decisions were "clearly inappropriate," while another 12 percent were "questionable."
The reclassified documents identified by historians included material that had been published by the State Department as part of an official history of foreign relations; a 1962 telegram in which the U.S. ambassador to Yugoslavia passed along an English translation of a Belgrade newspaper story; and the CIA's assessment on October 12, 1950, two weeks before China sent 300,000 troops into Korea, that Chinese intervention in the Korean War was "not probable in 1950." The audit revealed that in some cases the CIA had deliberately reclassified harmless material to draw attention away from truly sensitive documents removed at the same time.
Even when documents met the minimum criteria for classification, the audit found, removing them did not necessarily make sense, since they often were available from other sources and their sudden withdrawal served only to highlight their sensitive nature. The report added that "a significant number of records that were withdrawn had actually been created as unclassified documents but were subsequently classified by CIA at the time of re-review (often 50 years later) solely because they contained the name of a CIA official in the list of individuals provided a copy."