Collateral clearance

The United States government classification system is established under , the latest in a long series of executive orders on the topic. Issued by President Barack Obama in 2009, Executive Order 13526 replaced earlier executive orders on the topic and modified the regulations codified to 32 C.F.R. 2001. It lays out the system of classification, declassification, and handling of national security information generated by the U.S. government and its employees and contractors, as well as information received from other governments.

The desired degree of secrecy about such information is known as its sensitivity. Sensitivity is based upon a calculation of the damage to national security that the release of the information would cause. The United States has three levels of classification: Confidential, Secret, and Top Secret. Each level of classification indicates an increasing degree of sensitivity. Thus, if one holds a Top Secret security clearance, one is allowed to handle information up to the level of Top Secret, including Secret and Confidential information. If one holds a Secret clearance, one may not then handle Top Secret information, but may handle Secret and Confidential classified information.

The United States does not have British-style Official Secrets Act; instead, several laws protect classified information, including the Espionage Act of 1917, the Atomic Energy Act of 1954 and the Intelligence Identities Protection Act of 1982. A 2013 report to Congress noted that "...criminal statutes that may apply to the publication of classified defense information ... have been used almost exclusively to prosecute individuals with access to classified information (and a corresponding obligation to protect it), who make it available to foreign agents, or to foreign agents who obtain classified information unlawfully while present in the United States. While prosecutions appear to be on the rise, leaks of classified information to the press have relatively infrequently been punished as crimes, and we are aware of no case in which a publisher of information obtained through unauthorized disclosure by a government employee has been prosecuted for publishing it." The legislative and executive branches of government, including US presidents, have frequently leaked classified information to journalists. Congress has repeatedly resisted or failed to pass a law that generally outlaws disclosing classified information. Most espionage law only criminalizes national defense information; only a jury can decide if a given document meets that criterion, and judges have repeatedly said that being "classified" does not necessarily make information become related to the "national defense". Furthermore, by law, information may not be classified merely because it would be embarrassing or to cover illegal activity; information may only be classified to protect national security objectives.

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