What’s the Difference Between “Top Secret” and “Confidential”?

News reports about the lost-and-found Los Alamos hard drives have variously described their contents as “sensitive,” “secret,” and “confidential.” Are these terms interchangeable? What is their significance?

The executive agencies sort classified information into three categories of escalating sensitivity: “confidential,” “secret,” and “top secret.” “Confidential” applies to information whose release could “damage” national security, whereas secret carries with it the potential for “serious damage” and top secret “grave damage.” In practice, the definitions are flexible and each agency has adapted the terminology for its own use.

Currently, about 25 percent of all newly classified documents fall into the “confidential” category. More than two-thirds are labeled “secret,” and the remainder–roughly 10 percent–are graded “top secret.”

While any information can be classified–documents, cable traffic, and information from other sources–the government mostly applies it to documents. In 1998, the federal government classified more than 7 million documents, with the CIA classifying 40 percent of them, the Defense Department 29 percent, the National Reconnaissance Office 27 percent, and the Justice Department 2 percent. (The State Department accounted for 1 percent all classified documents, but that number does not include the hundreds of thousands of diplomatic cables sent each year.) The total number of classified documents is in the billions. In 1995, President Clinton signed an executive order requiring all new classified information to include a declassification date at its birth. All classified material older than 25 years must now be reviewed and, unless it meets a narrow exemption, be declassified. (Certain types of nuclear-weapon designs, for example, are exempted from automatic declassification.) More than 600 million pages of classified documents have been declassified in the last three years thanks to the Clinton order, compared with 250 million in the previous 15.

What types of things are kept classified?

Technological or military specifics, such as designs for nuclear weapons or information on how to disarm nuclear weapons (that’s what was on the Los Alamos lost hard drives). Data whose release would place its source in jeopardy, such as information obtained from a spy or the private communications of a member of a foreign government. Strategic knowledge, such as the intelligence community’s findings about another country’s military capabilities. Government initiatives that would prove embarrassing and damaging if made public, such as war plans against nations that are currently friendly.

Who classifies? The president and several agency heads and others they assign–“original classifiers,” as they are known. Of the government’s 4,000 original classifiers, only 800 can label something top secret. Additionally, new documents that draw on classified sources can be automatically classified.

Thousands of government employees and private contractors working on government projects are granted access to classified information on a “need to know” basis. By compartmentalizing a project’s secrets, need-to-know clearances keep all but a few employees from jeopardizing an entire project with leaks

The Los Alamos hard drives were classified secret. Had they been labeled top secret, Department of Energy guidelines would have required them to be logged out, and then only by employees with top secret clearance. But as secret materials, no accounting procedure was required and the drives could be accessed by dozens of DOE workers with secret clearance.

Next question?

Explainer thanks: Professor Timothy Hoyt, director of special programs, national security studies at Georgetown; Steve Garfinkel, director of the Information Security Oversight Office; and CIA spokesman Tom Crispell.