
Plausible deniability is the ability of people, typically senior officials in a formal or informal
chain of command
A command hierarchy is a group of people who carry out orders based on others' authority within the group.
Military chain of command
In a military context, the chain of command is the line of authority and responsibility along which orders ...
, to
deny knowledge or responsibility for actions committed by or on behalf of members of their organizational hierarchy. They may do so because of a lack of evidence that can confirm their participation, even if they were personally involved in or at least
willfully ignorant of the actions. If illegal or otherwise disreputable and unpopular activities become public, high-ranking officials may deny any awareness of such acts to insulate themselves and
shift the blame onto the agents who carried out the acts, as they are confident that their doubters will be unable to prove otherwise. The lack of evidence to the contrary ostensibly makes the denial plausible (credible), but sometimes, it makes any accusations only
unactionable.
The term typically implies forethought, such as intentionally setting up the conditions for the plausible avoidance of responsibility for one's future actions or knowledge. In some organizations, legal doctrines such as
command responsibility
In the practice of international law, command responsibility (also superior responsibility) is the legal doctrine of hierarchical accountability for war crimes, whereby a commanding officer (military) and a superior officer (civil) are legally r ...
exist to hold major parties responsible for the actions of subordinates who are involved in actions and nullify any legal protection that their denial of involvement would carry.
In
politics
Politics () is the set of activities that are associated with decision-making, making decisions in social group, groups, or other forms of power (social and political), power relations among individuals, such as the distribution of Social sta ...
and especially
espionage
Espionage, spying, or intelligence gathering, as a subfield of the intelligence field, is the act of obtaining secret or confidential information ( intelligence). A person who commits espionage on a mission-specific contract is called an ...
, deniability refers to the ability of a powerful player or intelligence agency to
pass the buck and to avoid
blowback by secretly arranging for an action to be taken on its behalf by a third party that is ostensibly unconnected with the major player. It allows politicians to avoid being directly associated with
negative campaigning
Negative campaigning is the process of deliberately spreading negative information about someone or something to damage their public image. A colloquial and more derogatory term for the practice is mudslinging.
Deliberate spreading of such in ...
, and enables them to denounce or disavow third-party
smear campaigns that use unethical approaches or potentially libelous innuendo against their political opponents.
Although plausible deniability has existed throughout history, the term is believed to have been coined by the
CIA
The Central Intelligence Agency (CIA; ) is a civilian foreign intelligence service of the federal government of the United States tasked with advancing national security through collecting and analyzing intelligence from around the world and ...
in the 1950s and was popularized during the
Watergate scandal
The Watergate scandal was a major political scandal in the United States involving the Presidency of Richard Nixon, administration of President Richard Nixon. The scandal began in 1972 and ultimately led to Resignation of Richard Nixon, Nix ...
in the 1970s.
Overview
Arguably, the key concept of plausible deniability is plausibility. It is relatively easy for a government official to issue a blanket denial of an action, and it is possible to destroy or cover up evidence after the fact, that might be sufficient to avoid a criminal prosecution, for instance. However, the public might well disbelieve the denial, particularly if there is strong circumstantial evidence or if the action is believed to be so unlikely that the only logical explanation is that the denial is false.
The concept is even more important in espionage. Intelligence may come from many sources, including
human sources. The exposure of information to which only a few people are privileged may directly implicate some of the people in the disclosure. An example is if an official is traveling secretly, and only one aide knows the specific travel plans. If that official is assassinated during his travels, and the circumstances of the assassination strongly suggest that the assassin had foreknowledge of the official's travel plans, the probable conclusion is that his aide has betrayed the official. There may be no direct evidence linking the aide to the assassin, but collaboration can be inferred from the facts alone, thus making the aide's denial implausible.
History
The term's roots go back to US President
Harry Truman
Harry S. Truman (May 8, 1884December 26, 1972) was the 33rd president of the United States, serving from 1945 to 1953. As the 34th vice president in 1945, he assumed the presidency upon the death of Franklin D. Roosevelt that year. Subsequen ...
's
National Security Council
A national security council (NSC) is usually an executive branch governmental body responsible for coordinating policy on national security issues and advising chief executives on matters related to national security. An NSC is often headed by a n ...
Paper 10/2 of June 18, 1948, which defined "covert operations" as "all activities (except as noted herein) which are conducted or sponsored by this Government against hostile foreign states or groups or in support of friendly foreign states or groups but which are so planned and executed that any US Government responsibility for them is not evident to unauthorized persons and that if uncovered the US Government can plausibly disclaim any responsibility for them." During the
Eisenhower administration
Dwight D. Eisenhower's tenure as the 34th president of the United States began with his first inauguration on January 20, 1953, and ended on January 20, 1961. Eisenhower, a Republican from Kansas, took office following his landslide victor ...
, NSC 10/2 was incorporated into the more-specific NSC 5412/2 "Covert Operations." NSC 5412 was declassified in 1977 and is located at the National Archives. The expression "plausibly deniable" was first used publicly by
Central Intelligence Agency
The Central Intelligence Agency (CIA; ) is a civilian foreign intelligence service of the federal government of the United States tasked with advancing national security through collecting and analyzing intelligence from around the world and ...
(CIA) Director
Allen Dulles
Allen Welsh Dulles ( ; April 7, 1893 – January 29, 1969) was an American lawyer who was the first civilian director of central intelligence (DCI), and its longest serving director. As head of the Central Intelligence Agency (CIA) during the ea ...
. The idea, on the other hand, is considerably older. For example, in the 19th century,
Charles Babbage
Charles Babbage (; 26 December 1791 – 18 October 1871) was an English polymath. A mathematician, philosopher, inventor and mechanical engineer, Babbage originated the concept of a digital programmable computer.
Babbage is considered ...
described the importance of having "a few simply honest men" on a committee who could be temporarily removed from the deliberations when "a peculiarly delicate question arises" so that one of them could "declare truly, if necessary, that he never was present at any meeting at which even a questionable course had been proposed."
Church Committee
The
Church Committee
The Church Committee (formally the United States Senate Select Committee to Study Governmental Operations with Respect to Intelligence Activities) was a US Senate select committee in 1975 that investigated abuses by the Central Intelligence ...
of the
U.S. Senate
The United States Senate is a chamber of the bicameral United States Congress; it is the upper house, with the U.S. House of Representatives being the lower house. Together, the Senate and House have the authority under Article One of the ...
conducted an investigation of the intelligence agencies in 1974–1975. In the course of the investigation, it was revealed that the
CIA
The Central Intelligence Agency (CIA; ) is a civilian foreign intelligence service of the federal government of the United States tasked with advancing national security through collecting and analyzing intelligence from around the world and ...
, going back to the
Kennedy administration
John F. Kennedy's tenure as the List of presidents of the United States, 35th president of the United States began with Inauguration of John F. Kennedy, his inauguration on January 20, 1961, and ended with Assassination of John F. Kennedy, his ...
, had plotted the assassination of a number of foreign leaders, including
Cuba
Cuba, officially the Republic of Cuba, is an island country, comprising the island of Cuba (largest island), Isla de la Juventud, and List of islands of Cuba, 4,195 islands, islets and cays surrounding the main island. It is located where the ...
's
Fidel Castro
Fidel Alejandro Castro Ruz (13 August 1926 – 25 November 2016) was a Cuban politician and revolutionary who was the leader of Cuba from 1959 to 2008, serving as the prime minister of Cuba from 1959 to 1976 and President of Cuba, president ...
, but the president himself, who clearly supported such actions, was not to be directly involved so that he could deny knowledge of it. That was given the term "plausible denial."
Plausible denial involves the creation of power structures and chains of command loose and informal enough to be denied if necessary. The idea was that the CIA and later other bodies could be given controversial instructions by powerful figures, including the
president
President most commonly refers to:
*President (corporate title)
* President (education), a leader of a college or university
*President (government title)
President may also refer to:
Arts and entertainment Film and television
*'' Præsident ...
himself, but that the existence and true source of those instructions could be denied if necessary if, for example, an operation went disastrously wrong and it was necessary for the administration to disclaim responsibility.
Later legislative barriers
The
Hughes–Ryan Act of 1974 sought to put an end to plausible denial by requiring a presidential finding for each operation to be important to national security, and the
Intelligence Oversight Act of 1980 required for Congress to be notified of all
covert operations
A covert operation or undercover operation is a military or police operation involving a covert agent or troops acting under an assumed cover to conceal the identity of the party responsible.
US law
Under US law, the Central Intelligence Ag ...
. Both laws, however, are full of enough vague terms and escape hatches to allow the executive branch to thwart their authors' intentions, as was shown by the
Iran–Contra affair
The Iran–Contra affair (; ), also referred to as the Iran–Contra scandal, the Iran Initiative, or simply Iran–Contra, was a political scandal in the United States that centered on arms trafficking to Iran between 1981 and 1986, facilitat ...
. Indeed, the members of Congress are in a dilemma since when they are informed, they are in no position to stop the action, unless they leak its existence and thereby foreclose the option of covertness.
New York Times
''The New York Times'' (''NYT'') is an American daily newspaper based in New York City. ''The New York Times'' covers domestic, national, and international news, and publishes opinion pieces, investigative reports, and reviews. As one of ...
Under Cover, or Out of Control? November 29, 1987 Section 7; p. 3, Column 1 ''(Book Review of 2 books: The Perfect Failure and Covert Action)''
Media reports
Iran–Contra affair
In his testimony to the congressional committee studying the
Iran–Contra affair
The Iran–Contra affair (; ), also referred to as the Iran–Contra scandal, the Iran Initiative, or simply Iran–Contra, was a political scandal in the United States that centered on arms trafficking to Iran between 1981 and 1986, facilitat ...
, Vice Admiral
John Poindexter
John Marlan Poindexter (born August 12, 1936) is a retired United States naval officer and Department of Defense official. He was Deputy National Security Advisor and National Security Advisor during the Reagan administration. He was convicte ...
stated: "I made a deliberate decision not to ask the President, so that I could insulate him from the decision and provide some future deniability for the President if it ever leaked out."
Declassified government documents
* A telegram from the Ambassador in Vietnam
Henry Cabot Lodge Jr.
Henry Cabot Lodge Jr. (July 5, 1902 – February 27, 1985) was an American diplomat and politician who represented Massachusetts in the United States Senate and served as United States Ambassador to the United Nations in the administration of Pre ...
, to Special Assistant for National Security Affairs
McGeorge Bundy
McGeorge "Mac" Bundy (March 30, 1919 – September 16, 1996) was an American academic who served as the U.S. National Security Advisor to Presidents John F. Kennedy and Lyndon B. Johnson from 1961 through 1966. He was president of the Ford Fou ...
on US options with respect to a possible coup, mentions plausible denial.
* CIA and White House documents on covert political intervention in the 1964 Chilean election have been declassified. The CIA's Chief of Western Hemisphere Division, J.C. King, recommended for funds for the campaign to "be provided in a fashion causing (
Eduardo Frei Montalva
Eduardo Nicanor Frei Montalva (; 16 January 1911 – 22 January 1982) was a Chileans, Chilean political leader. In his long political career, he was Minister of Public Works, president of his Christian Democratic Party (Chile), Christia ...
president of Chile) to infer United States origin of funds and yet permitting plausible denial."
* Training files of the CIA's covert "
Operation PBSuccess" for the 1954 coup in Guatemala describe plausible deniability. According to the
National Security Archive
The National Security Archive is a 501(c)(3) non-governmental, non-profit research and archival institution located on the campus of the George Washington University in Washington, D.C. Founded in 1985 to check rising government secrecy, the N ...
: "Among the documents found in the training files of Operation PBSuccess and declassified by the Agency is a CIA document titled 'A Study of Assassination.' A how-to guide book in the art of political killing, the 19-page manual offers detailed descriptions of the procedures, instruments, and implementation of assassination." The manual states that to provide plausible denial, "no assassination instructions should ever be written or recorded."
Soviet operations
In the 1980s, the Soviet
KGB
The Committee for State Security (, ), abbreviated as KGB (, ; ) was the main security agency of the Soviet Union from 1954 to 1991. It was the direct successor of preceding Soviet secret police agencies including the Cheka, Joint State Polit ...
ran
OPERATION INFEKTION (also called "OPERATION DENVER"), which utilised the East German
Stasi
The Ministry for State Security (, ; abbreviated MfS), commonly known as the (, an abbreviation of ), was the Intelligence agency, state security service and secret police of East Germany from 1950 to 1990. It was one of the most repressive pol ...
and Soviet-affiliated press to spread the idea that HIV/AIDS was an engineered bioweapon. The Stasi acquired plausible deniability on the operation by covertly supporting biologist
Jakob Segal
Jakob Segal (17 April 1911 – 30 September 1995) was a Russian-born German biology professor at Humboldt University of Berlin in the former East Germany. He was one of the advocates of the conspiracy theory that HIV was created by the United Sta ...
, whose stories were picked up by international press, including "numerous bourgeois newspapers" such as the ''
Sunday Express
The ''Daily Express'' is a national daily United Kingdom middle-market newspaper printed in tabloid format. Published in London, it is the flagship of Express Newspapers, owned by publisher Reach plc. It was first published as a broadsheet ...
''. Publications in third-party countries were then cited as the originators of the claims. Meanwhile, Soviet intelligence obtained plausible deniability by utilising the German Stasi in the disinformation operation.
Little green men and Wagner Group
In 2014, "
Little green men"—troops without insignia carrying modern Russian military equipment—emerged at the start of the
Russo-Ukrainian War
The Russo-Ukrainian War began in February 2014 and is ongoing. Following Ukraine's Revolution of Dignity, Russia Russian occupation of Crimea, occupied and Annexation of Crimea by the Russian Federation, annexed Crimea from Ukraine. It then ...
, which ''
The Moscow Times
''The Moscow Times'' (''MT'') is an Amsterdam-based independent English-language and Russian-language online newspaper. It was in print in Russia from 1992 until 2017 and was distributed free of charge at places frequented by English-speaking to ...
'' described as a tactic of plausible deniability.
The
Wagner Group
The Wagner Group (), officially known as PMC Wagner (, ), is a Russian state-funded private military company (PMC) controlled 2023 Wagner Group plane crash, until 2023 by Yevgeny Prigozhin, a former close ally of Russia's president Vladimir Pu ...
, a Russian
private military company, has been described as an attempt at plausible deniability for Kremlin-backed interventions in Ukraine, Syria, and in various interventions in Africa.
Flaws
* It is an open door to the abuse of authority by requiring that the parties in question to be said to be able to have acted independently, which, in the end, is tantamount to giving them license to act independently.
* The denials are sometimes seen as plausible but sometimes seen through by both the media and the populace.
* Plausible deniability increases the risk of misunderstanding between senior officials and their employees.
Other examples
Another example of plausible deniability is someone who actively avoids gaining certain knowledge of facts because it benefits that person not to know.
As an example, a
lawyer
A lawyer is a person who is qualified to offer advice about the law, draft legal documents, or represent individuals in legal matters.
The exact nature of a lawyer's work varies depending on the legal jurisdiction and the legal system, as w ...
may suspect that facts exist that would hurt his case but decide not to investigate the issue because if he has actual knowledge, the rules of ethics might require him to reveal the facts to the opposing side.
Council on Foreign Relations
Use in computer networks
In computer networks, plausible deniability often refers to a situation in which people can deny transmitting a file, even when it is proven to come from their computer.
That is sometimes done by setting the computer to relay certain types of broadcasts automatically in such a way that the original transmitter of a file is indistinguishable from those who are merely relaying it. In that way, those who first transmitted the file can claim that their computer had merely relayed it from elsewhere. This principle is used in the
opentracker
Opentracker is a free (licensed as beerware) BitTorrent peer tracker software (a special kind of HTTP or UDP server software) that is designed to be fast and to have a low consumption of system resources.
Features
Several instances of open ...
bittorrent
BitTorrent is a Protocol (computing), communication protocol for peer-to-peer file sharing (P2P), which enables users to distribute data and electronic files over the Internet in a Decentralised system, decentralized manner. The protocol is d ...
implementation by including random IP addresses in peer lists.
In encrypted messaging protocols, such as
bitmessage, every user on the network keeps a copy of every message, but is only able to decrypt their own and that can only be done by trying to decrypt every single message. Using this approach it is impossible to determine who sent a message to whom without being able to decrypt it. As everyone receives everything and the outcome of the decryption process is kept private.
It can also be done by a
VPN
Virtual private network (VPN) is a network architecture for virtually extending a private network (i.e. any computer network which is not the public Internet) across one or multiple other networks which are either untrusted (as they are not c ...
if the host is not known.
In any case, that claim cannot be disproven without a complete decrypted log of all network connections.
Freenet file sharing
The
Freenet
Hyphanet (until mid-2023: Freenet) is a peer-to-peer platform for censorship-resistant, Anonymity application, anonymous communication. It uses a decentralized distributed data store to keep and deliver information, and has a suite of free soft ...
file sharing
File sharing is the practice of distributing or providing access to digital media, such as computer programs, multimedia (audio, images and video), documents or electronic books. Common methods of storage, transmission and dispersion include ...
network is another application of the idea by obfuscating data sources and flows to protect operators and users of the network by preventing them and, by extension, observers such as
censors
Censorship is the suppression of speech, public communication, or other information. This may be done on the basis that such material is considered objectionable, harmful, sensitive, or "inconvenient". Censorship can be conducted by governmen ...
from knowing where data comes from and where it is stored.
Use in cryptography
In
cryptography
Cryptography, or cryptology (from "hidden, secret"; and ''graphein'', "to write", or ''-logy, -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of Adversary (cryptography), ...
,
deniable encryption
In cryptography and steganography, plausibly deniable encryption describes encryption techniques where the existence of an encrypted file or message is deniable in the sense that an adversary cannot prove that the plaintext data exists.
The use ...
may be used to describe
steganographic techniques in which the very existence of an encrypted file or message is deniable in the sense that an adversary cannot prove that an encrypted message exists. In that case, the system is said to be "fully undetectable".
Some systems take this further, such as
MaruTukku,
FreeOTFE
FreeOTFE is a discontinued open source computer program for on-the-fly disk encryption (OTFE). On Microsoft Windows, and Windows Mobile (using FreeOTFE4PDA), it can create a virtual drive within a file or partition, to which anything written i ...
and (to a much lesser extent)
TrueCrypt
TrueCrypt is a discontinued source-available freeware utility software, utility used for on-the-fly encryption (OTFE). It can create a virtual encrypted disk within a file, encrypt a Disk partitioning, partition, or encrypt the whole Data storag ...
and
VeraCrypt
VeraCrypt is a free and open-source utility for on-the-fly encryption (OTFE). The software can create a virtual encrypted disk that works just like a regular disk but within a file. It can also encrypt a partition or (in Windows) the entire sto ...
, which nest encrypted data. The owner of the encrypted data may reveal one or more keys to decrypt certain information from it, and then deny that more keys exist, a statement which cannot be disproven without knowledge of all encryption keys involved. The existence of "hidden" data within the overtly encrypted data is then ''deniable'' in the sense that it cannot be proven to exist.
''“Trepidation of Relationship”'' and ''“Trepidation of Memory”'' are two further cryptogaphical concepts to discuss plausible deniability, as also compared in a Youtube-Audio-Podcast.
*"Trepidation of Memory“ refers to the temporal decoupling of
key pairs. In the book “Super Secreto” by Theo Tenzer, the developer Textbrowser's idea for the Spot-On Encryption Suite application describes how the assignment of public and private keys can become blurred over time. The use of
ephemeral keys, which only exist temporarily, makes the
traceability
Traceability is the capability to trace something. In some cases, it is interpreted as the ability to verify the history, location, or application of an item by means of documented recorded identification.
Other common definitions include the capa ...
of communication more difficult. The collision of two asteroids is used a[s a figurative analogy: After the collision, the two original objects are no longer identifiable as they have disintegrated into individual parts and are moving away from each other. The new paradigm is to separate public and private keys again after they have been used, in the case of asymmetric encryption, or to remove the temporary, ephemeral key from the content in the case of symmetric encryption.
*"Trepidation of Relationship” builds on this concept and refers to the relationships between users in a network. The use of human proxies, i.e. friends in the messenger's friends list who forward messages on behalf of others, makes it more difficult to *identify the actual sender*. This innovative concept has been implemented in the messenger Spot-On Encryption Suite by the developer Textbrowser and then described in the book Human Proxies by Uni Nurf.
Human Proxies offer new directions to end-to-end encryption: End-A-to-End-Z encryption must be rethought when it turns out to be an End-B-to-End-Z encryption. Since the key exchange with the proxy may have taken place in the past, the relationship may not be recognizable to external analysts if a user uses an old friend who has not been contacted or chatted with for a long time as a human proxy. The construct of the *Inner Envelope* behind the Human Proxy function also creates new cryptographic challenges, provides plausible deniability to included nodes, and offers new perspectives in encryption, its analysis and decryption: As all messages in the network are encrypted, end-to-end encryption is new defined and gets with Human Proxies a potential second and plausible deniable start point.
These cryptographic concepts serve to protect
privacy
Privacy (, ) is the ability of an individual or group to seclude themselves or information about themselves, and thereby express themselves selectively.
The domain of privacy partially overlaps with security, which can include the concepts of a ...
and increase
security
Security is protection from, or resilience against, potential harm (or other unwanted coercion). Beneficiaries (technically referents) of security may be persons and social groups, objects and institutions, ecosystems, or any other entity or ...
in
networks
Network, networking and networked may refer to:
Science and technology
* Network theory, the study of graphs as a representation of relations between discrete objects
* Network science, an academic field that studies complex networks
Mathematics
...
. They make
mass surveillance
Mass surveillance is the intricate surveillance of an entire or a substantial fraction of a population in order to monitor that group of citizens. The surveillance is often carried out by Local government, local and federal governments or intell ...
more difficult and enable plausible deniability. Both concepts can be summarized as follows:
*''Trepidation of Memory:'' Makes it difficult to trace key pairs back in time.
*''Trepidation of Relationship:'' Makes it difficult to identify communication relationships in a network.
Programming
The
Underhanded C Contest
The Underhanded C Contest was a programming contest to turn out code that is malicious, but passes a rigorous inspection, and looks like an honest mistake even if discovered. The contest rules define a task, and a malicious component. Entries ...
is an annual programming contest involving the creation of carefully crafted defects, which have to be both very hard to find and plausibly deniable as mistakes once found.
See also
References
Further reading
*
*
*
*
*
External links
{{Wiktionary
*
Sections of the Church Committee about plausible denial on wikisource.org
Church Committee reports (Assassination Archives and Research Center)Church Report: Covert Action in Chile 1963-1973 (U.S. Dept. of State)Original 255 pages of Church Committee "Findings and Conclusions" in pdf file
Central Intelligence Agency operations
Political terminology
Military terminology
Euphemisms
Accountability