Classified Information: Definition, Examples, and Laws

Man wearing pinstripe suit holding confidential top secret file.
Man wearing pinstripe suit holding confidential top secret file.

Peter Dazeley / Getty Images

Classified information is material deemed by government officials to be so sensitive that it must be protected. Laws or regulations restrict access to such classified information to people with the necessary security clearance and “need to know.” In some instances, misuse and mishandling of the material can result in criminal penalties.

Key Takeaways: Classified Information

  • Classified information is material that if made public could endanger US national security.
  • Sensitive information may be classified as Confidential, Secret, or Top Secret, depending on its potential impact on national security.
  • Presidents periodically issue executive orders that govern the classification and declassification of sensitive material.
  • The legal basis for the classification system comes from the president’s constitutional authority as Commander in Chief of the U.S. military.
  • Access to classified information is restricted to officials with proper security clearances and a demonstrable “need to know.”

Classified Information in the US 

In the United States, classified information requires protection against unauthorized disclosure in the interests of national defense and security or foreign relations and is to be handled according to Federal law or presidential executive order. The term includes Restricted Data, Formerly Restricted Data, and National Security Information. The potential damage to the national security of each is denoted by the classification levels Confidential, Secret, or Top Secret. The choice of level is based on an impact assessment which includes methods for determining the classification level of the information and rules on how to protect information classified at each level. This assessment process typically requires security clearances for personnel evaluating the information.

The legal basis for the classification system comes from the president’s constitutional authority as Commander in Chief of the U.S. military. Presidents have established and developed it through a series of executive orders dating to the era encompassing World War II and the early Cold War.

Since Franklin D. Roosevelt, presidents have issued executive orders that govern the classified information system. The most recent order, issued by President Barack Obama on December 29, 2009, is Executive Order 13526, (E.O. 13526).

As outlined in the executive order, the president and certain other high-level executive and defense officials may designate officials as “original classification authorities” (“OCAs”). OCAs are individuals authorized in writing, either by the president, the vice president or agency heads, or other officials designated by the president, to originally classify information in the first place.

E.O. 13526, like those that preceded it, recognizes that while the public must be informed concerning the activities of its Government, the interests of the United States and its citizens require that certain information concerning national defense and foreign relations be protected against unauthorized disclosure. Under the order, information may not be designated as classified unless its disclosure could reasonably be expected to cause damage to national security.

Under the executive order, information can be classified in the first instance only if it pertains to at least one of seven topics:

  • military plans, weapons systems, or operations;
  • foreign government information [i.e., information received from foreign governments, with an expectation of confidentiality;
  • intelligence activities (including covert action), intelligence sources or methods, or cryptology;
  • foreign relations or foreign activities of the United States, including confidential sources;
  • scientific, technological, or economic matters relating to national security;
  • United States Government programs for safeguarding nuclear materials or facilities;
  • vulnerabilities or capabilities of systems, installations, infrastructures, projects, plans, or protection services relating to national security; or
  • the development, production, or use of weapons of mass destruction.

For the most part, the classification system is enforced by bureaucratic controls rather than by criminal law. The main punishment for mishandling of classified information is administrative—officials can be demoted, lose their security clearances, and be fired.

As such, the classification system exists in parallel to separate criminal penalties Congress has imposed to protect secret information deemed particularly critical to national security.

For example, the Espionage Act of 1917 protects secrets that it defines as defense-related information that could harm the United States or aid a foreign adversary. It does not refer to classification status, and prosecutors in an Espionage Act case do not need to prove that anything was deemed classified as an element of a crime. Persons convicted of violating the Espionage Act could be subject to fines of $10,000 and up to 20 years in prison.

A rare instance in which Congress has tied a law to the classification system is Section 1924 of Title 18 of the U.S. Code, which makes the “unauthorized retention or removal of classified material” a crime, so prosecutors would have to show that the information remained technically classified as an element of proving that offense to a jury.

The Presidential Records Act of 1978 requires that all official documents and other material or information a president or a vice president may have generated or obtained while in office belong to the American people, and thus must go to the National Archives and Records Administration (NARA) for retention and preservation.

Classification Levels

"Secret-Restricted Data" cover sheet
"Secret-Restricted Data" cover sheet.

Washington, DC, Wikimedia Commons free media repository

According to the executive order, National security information is to be classified at one of the following three levels from lowest to highest:

Confidential—applies to information, the unauthorized disclosure of which could reasonably be expected to cause “damage” to national security.

Secret—applies to information, the unauthorized disclosure of which could reasonably be expected to cause “serious damage” to national security.

Top Secret—applies to information, the unauthorized disclosure of which could reasonably be expected to cause “exceptionally grave damage” to national security. Examples of exceptionally grave damage include "armed hostilities against the United States or its allies; disruption of foreign relations vitally affecting the national security; the compromise of vital defense plans or complex cryptologic and communications intelligence systems; the revelation of sensitive intelligence operations; and the disclosure of scientific or technical developments vital to national security."

The order also allows the departments of State, Defense, Energy, Homeland Security, and Justice, along with the Office of the Director of National Intelligence, to designate “special access programs,” subsets of classified information that are more tightly controlled.

Access to such particularly sensitive information is further restricted with a designation of S.C.I., for Sensitive Compartmented Information. All SCI must be handled within formal access control systems established by the Director of National Intelligence. Though it is sometimes called “Above Top Secret,” SCI is not a classification level. Information at any classification level may be marked for SCI control. SCI information must be processed, stored, used, or discussed in a Sensitive Compartmented Information Facility.

The SCI system helps the intelligence community manage access to particular categories of information among people with access to the appropriate level of classification. So a person with a “top secret” security clearance will ordinarily have access only to a subset of “compartments” within the SCI classification level.

The executive branch has regulations laying out the process that should be followed, such as a requirement to make sure that other agencies and departments with an interest in the secret are consulted. There are also procedures for the removal of classification markings on documents.

The appropriate classification level would be expected to be determined by the information disclosure risks because those risks largely determine the “magnitude of the net damage” that could be caused by such disclosure.

Access to classified information is restricted. Any documents containing that information are supposed to be marked accordingly, and only officials with proper security clearances and a demonstrable “need to know” are permitted to see them or be told of their contents. There are also rules limiting how such documents can be stored, physically transported, or electronically transmitted. A variety of markings are used for material that is not classified, but whose distribution is limited administratively or by other laws. For example, “For Official Use Only” or “Sensitive but Unclassified.”

Information related to the design of nuclear weapons is protected separately under the Atomic Energy Act of 1954. The term "Restricted Data" is used to denote information about certain nuclear technology. Information about the storage, use, or handling of nuclear material or weapons is marked "Formerly Restricted Data.” These designations are used in addition to the Confidential, Secret, and Top Secret level markings. Information protected by the Atomic Energy Act is protected by law and information classified under the Executive Order is protected by the doctrine of presidential executive privilege.

Some political science and legal experts argue that the definition of classified information should be expanded to include information that if disclosed, would cause injury to the cause of individual justice and human rights, rather than information that would cause injury to national security alone. Doing so, they suggest, would be in the collective best interest of a just society rather than the best interest of a society possibly acting unjustly, to protect its government or administrative officials from legitimate recourses consistent with a fair and just social contract.


As time passes and issues are either resolved or fade in importance, some classified information can become less sensitive and may be declassified and made public. Since 1967, the Freedom of Information Act has deemed that the public has the right to all information that is not considered to be damaging if released. Sometimes documents are declassified and released with information still considered confidential, obscured or “redacted.”

Redacted document in English with censored words blacked-out.
Redacted document in English with censored words blacked-out.

Christopher Ames / Getty Images

The executive branch has guidelines laying out the declassification processes that should be followed, such as a requirement to make sure that other agencies and departments with an interest in the information are consulted. There are also procedures for the removal of classification markings on documents.

Generally, officials who have been designated as “original classification authorities” in federal departments and agencies can declassify information. In doing so, they are legally considered to be exercising the president’s power over such matters.

Executive Order 13526 directs the head of the department or agency that originally deemed information classified to oversee declassification reviews, and it sets some standards by which they should do so.

Under the order, documents may remain classified no longer than is absolutely necessary to protect national security, and agencies must make every effort to declassify documents as soon as possible. Declassification does not necessarily lead to immediate public release because some documents may still be withheld from release under exemptions contained in the Freedom of Information Act or when other public laws prevent release.

There are three primary ways by which classified information may be declassified: Automatic Declassification, Systematic Review, and Mandatory Review.

Automatic Declassification

Automatic declassification is the declassification of “records of permanent historical value” based upon the occurrence of a specific date or event as determined by the original classification authority or the expiration of a maximum time frame for the duration of classification established under the Order. Generally, records of permanent historical value are classified for no longer than 25 years and many are declassified sooner.

The automatic declassification process increases the potential release of formerly classified national security information to the general public and researchers, enhancing their knowledge of the United States’ democratic institutions and history, while at the same time ensuring that information that can still cause damage to national security continues to be protected.

Systematic Review

Systematic declassification means the review for declassification of classified information contained in records of permanent historical value. The classifying organizations periodically review classified documents contained in these records for possible declassification.

Mandatory Review

Executive Order 13526 requires the classifying agencies to review for declassification of classified documents or other classified material, such as electronic files, whenever there is a Freedom of Information request for it that is sufficiently specific to enable the department to locate it with a reasonable amount of effort.

Presidential Power to Declassify Information

While Executive Order 13526 establishes procedures by which federal agencies may declassify information, the power of the president to do so is a very different legal issue. 

The question of presidential power to declassify information gained nationwide attention in August 2022 when the U.S. Department of Justice accused Former President Donald Trump of violating the Presidential Records Act by taking classified government documents, including some marked “Top Secret.” with him when he left office and storing them at his Mar-a-Lago resort home. Attorney General Merrick Garland indicated at the time that Trump was being investigated for potential violations of the Espionage Act and obstruction of justice laws. 

During the investigation, Trump claimed that, through his presidential powers, he had declassified the information before leaving office. In general, presidents can directly declassify information because doing so is ultimately within their constitutional authority.

On January 8, 2023, the White House said that President Joe Biden’s legal team had discovered “a small number” of classified documents in Biden’s former office at a Washington think tank last fall. On January 9, the Justice Department was considering how to proceed in deciding whether or not to appoint a special counsel, like the one investigating former President Trump’s hoarding of sensitive documents and failure to return all of them.

The documents found in Mr. Biden’s former office, which date to his time as vice president, were found by his personal lawyers on Nov. 2, when they were packing files at the Penn Biden Center for Diplomacy and Global Engagement, according to the White House. Officials did not describe precisely how many documents were involved, what kind of information they included or their level of classification.

The White House said in a statement that the White House Counsel’s Office notified the National Archives and Records Administration on the same day the documents were found “in a locked closet” and that the agency retrieved them the next morning.

Typically, presidents who want to declassify information direct their subordinates overseeing the department or agency with primary responsibility for the information to review the information to make some or all of it public. On rare occasions, however, presidents have unilaterally declassified something.

For example, in 2004, President George W. Bush himself declassified a portion of his presidential daily intelligence briefing from August 2001—one month before the Sept. 11 terrorist attacks—labeled: “Bin Laden Determined to Strike in U.S.”

No Supreme Court precedent definitively answers the question of whether presidents must follow any legally prescribed procedures for declassifying information.

In 2020, a federal appeals court held that “declassification, even by the president, must follow established procedures.” But the context was different: The court’s statement was part of a decision rejecting a Freedom of Information Act lawsuit involving whether President Trump had effectively declassified a covert CIA program to arm and train Syrian rebels fighting to remove Bashar al-Assad from power by discussing the program’s existence in a tweet.

According to specialists in the law of government secrecy, the question of whether presidents can secretly declassify information without leaving a written record or telling anyone of the fact is largely unanswered.

Under Executive Order 13526, if there is no written or witnessed spoken directive memorializing a decision to declassify information and conveying that decision to the rest of the government, the action might essentially have no consequence. Departments and agencies could continue to consider that information classified and continue to treat it as a closely held secret, restricting access to records containing it, including denial of Freedom of Information Act requests.


  • “The Protection of Classified Information: The Legal Framework.” Congressional Research Service, August 12, 2022,
  • Fein, Bruce E. “Access to Classified Information: Constitutional and Statutory Dimensions.” William & Mary Law Review, 1985,
  • “Executive Order 13526- Classified National Security Information.” The White House, December 29, 2009,
  • Turner, Stansfield. “Burn Before Reading: Presidents, CIA Directors, and Secret Intelligence.” Hachette Books, October 1, 2005, ISBN-10: ‎0786867825
  • Reagan, Robert Timothy. “Keeping Government Secrets: A Pocket Guide on the State-Secrets Privilege, the Classified Information Procedures Act, and Classified Information Security Officers.” CreateSpace Independent Publishing Platform, January 1, 2017, ISBN-10: ‎1541389794.
  • Ward, Alex. “Trump just revealed a covert CIA program over Twitter.” Vox, July 25, 2017,
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Longley, Robert. "Classified Information: Definition, Examples, and Laws." ThoughtCo, Jan. 10, 2023, Longley, Robert. (2023, January 10). Classified Information: Definition, Examples, and Laws. Retrieved from Longley, Robert. "Classified Information: Definition, Examples, and Laws." ThoughtCo. (accessed February 9, 2023).