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Mark Fallon

Mark Fallon is a former Naval Criminal Investigative Service (NCIS) special agent and U.S. counterterrorism expert. He served as the Special Agent-in-Charge and Deputy Commander of the U.S. Department of Defense's Criminal Investigation Task Force (CITF) at the Guantánamo Bay detention facility for two and a half years.

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Mark Fallon
Fallon in 2015
OccupationCounter-terrorism expert
Known forObjecting to the use of torture in interrogation
Websitehttp://markfallon.us

Mark Fallon is a former Naval Criminal Investigative Service (NCIS) special agent and U.S. counterterrorism expert.1234 He served as the Special Agent-in-Charge and Deputy Commander of the U.S. Department of Defense's Criminal Investigation Task Force (CITF) at the Guantánamo Bay detention facility for two and a half years. 567

Under his leadership, the CITF conducted independent criminal investigations, interrogations, and intelligence analysis in parallel with the efforts of Joint Task Force Guantánamo, the Central Intelligence Agency (CIA), and the Federal Bureau of Investigation (FBI).

Fallon tried to use his influence to prevent torture from being employed at Guantanamo, emphasizing skills from police work of building rapport. "Our folks would sit on the ground with detainees having tea," Fallon told investigative reporter Bill Dedman of NBC News in the first report on the unit's efforts in 2006. "Many of the detainees wanted also to be released. And our goal was to obtain accurate information. A good investigator works hard to prove guilt or innocence." The NCIS team "suggested alternatives to the Army commanders in charge of the Guantanamo intelligence interrogations ... refused to participate in interrogations they felt were abusive; reported any signs of criminal acts by the intelligence interrogators; blocked an FBI plan to move Mohammed al-Qahtani to another country where he could be tortured; and threatened to remove their investigators from Guantanamo entirely if they were forced to watch abusive interrogations," NBC reported.8910

But they were shut out of decisions by the Bush administration.11 According to Ben Taub, writing in the New Yorker magazine in 2019, by August 2002 "Fallon's élite interagency criminal-investigation task force had been sidelined."12

Following his time in Government service Fallon became a vocal critic of the US Intelligence Establishment's counter-terrorism efforts.131415

On 2008 Fallon joined The Soufan Group, a security firm founded by Ali Soufan, a former FBI counter-terrorism expert who also became a critic of the narrative common from members of the US Intelligence Establishment.1617

The American Civil Liberties Union mounted a defense of Fallon's First Amendment right to free speech, and contacted several members of Congress.18

Post-government career

After retiring from federal service in 2010, Fallon became the Director of ClubFed, LLC, a consultancy focused on ethical leadership, investigative interviewing, evidence-based policing, and science-based interrogation practices.

He has served as an expert witness, lecturer, and advisor on topics related to law enforcement, interrogation, and national security. Fallon has been involved with several organizations, including the Center for Ethics and the Rule of Law at the University of Pennsylvania, where he serves on the Advisory Council; Project Aletheia at John Jay College of Criminal Justice, which he co-founded and where he serves as Director-Emeritus; ETiCA Global, where he serves on the Advisory Board; and the Méndez Principles, where he has participated as a member of the Steering Committee of Experts. 19

Fallon previously served as Chair of the High-Value Detainee Interrogation Group Research Committee.

Fallon and Maria Hartwig, a psychologist at John Jay College of Criminal Justice at City University of New York, are developing a training curriculum for investigators based in actual science related to lying and deception.20

Principles on Effective Interviewing for Investigations and Information Gathering (Méndez Principles)

In 2016 the Special Rapporteur on torture and other cruel, inhuman or degrading treatment or punishment, Prof. Juan E. Méndez, submitted a thematic report to the United Nations General Assembly calling for the development of international standards for interviews based on scientific research, legal safeguards and ethical principles.21 Mark Fallon was a member of the global Steering Committee who guided the process of drafting such a document, consulting an Advisory Council comprising more than 80 experts from over 40 countries. In 2021, the Principles on Effective Interviewing for Investigations and Information Gathering was approved by the Steering Committee to realize the call.2223 These principles are also referred to as the Méndez Principles to honor Juan Méndez.

Books

Fallon is the author of ''Unjustifiable Means: The Inside Story of How the CIA, Pentagon and U.S. Government Conspired to Torture'' (2017), a memoir and non-fiction account of his experiences within the U.S. national security system after the September 11 attacks. The book recounts his personal involvement in counterterrorism investigations, including his time as Chief Investigator for the NCIS-led Criminal Investigation Task Force at Guantánamo Bay. It examines the development and use of enhanced interrogation techniques and discusses his concerns regarding interrogation policies and government accountability.

Fallon said that he faced significant resistance from the government in publishing the book, including extended delays and the censorship of 113 passages, often involving information he argued was already part of the congressional record. Department of Defense spokesman Darrell Walker disputed claims that the government was attempting to suppress publication, stating that the delays resulted from the book requiring review by ten different government agencies rather than from an effort to prevent its release. 242526

Fallon is also co-editor of ''Interrogation and Torture: Integrating Efficacy with Law and Morality'' and ''Interviewing and Interrogation: A Review of History and Practice Since World War II''. He also contributed to the ''International Handbook of Policing Crises and Emergencies''.

Film and television appearances

Fallon has appeared in documentaries, television programs, and media productions discussing counterterrorism, interrogation practices, and the legacy of post-9/11 security policies. His experiences as a former NCIS Special Agent and Chief Investigator have been featured in productions examining Guantánamo Bay, enhanced interrogation techniques, and issues of government accountability and human rights.

His media appearances include:

In 2026, Fallon participated in the documentary ''Leaving Hotel California: A Guantánamo Insider Story''. The documentary follows the first meeting between Fallon and Mohamedou Ould Slahi, a former Guantánamo detainee who was held for 15 years without charge. Through their conversation, the film explores themes of justice, resilience, forgiveness, and shared humanity, while examining the personal and historical impact of post-9/11 counterterrorism policies, interrogation practices, and the legacy of the Guantánamo Bay detention facility.

It also features former CIA officer John Kiriakou and presents different perspectives on the War on Terror, government accountability, and the consequences of counterterrorism policies. The documentary, which has completed production, is awaiting release and distribution.

References

References

  1. "Can US shed learned legal helplessness of Guantanamo's courts?". Newsweek. 2026-06-02. Retrieved 2026-07-14.
  2. Hartwig, Maria; Fallon, Mark (2022-09-14). "The manipulation of minds: reckoning with the legacy of the American post 9/11 torture program". Torture Journal. 32 (3): 71–83. doi:10.7146/torture.v32i3.131962. ISSN 1997-3322.
  3. Fallon, Mark (2019-04-02). "Opinion | The Government Had to Approve This Op-Ed". The New York Times. ISSN 0362-4331. Retrieved 2026-07-14.
  4. "Terrorist Threats Made U.S. as Brutal as Its Enemies". Newsweek. 2017-11-01. Retrieved 2026-07-14.
  5. Marre, Klaus (2016-10-05). "Guantanamo Bay's (Other) Dirty Secret". WhoWhatWhy. Retrieved 2026-07-14.
  6. "Conference on World Affairs", Wikipedia, 2026-04-17, retrieved 2026-07-14
  7. "Storied NCIS Career – MarkFallon.US". Retrieved 2026-07-14.
  8. "Can the '20th hijacker' of Sept. 11 stand trial?" (PDF). NBC News. October 24, 2006.
  9. https://www.nbcnews.com/id/wbna15361458
  10. https://www.nbcnews.com/id/wbna15361462
  11. Taub, Ben (2019-04-20). "How the War on Terror Is Being Written". New Yorker magazine. Retrieved 2019-10-05. In his role as the deputy commander of the detention camp's Criminal Investigation Task Force, Fallon had spent the previous months trying to prevent the military from adopting abusive interrogation practices.
  12. Taub, Ben (2019-04-15). "Guantánamo's Darkest Secret". New Yorker magazine. Retrieved 2019-10-05. By the time Salahi arrived at Guantánamo, on August 5, 2002, Fallon's élite interagency criminal-investigation task force had been sidelined, and Lehnert had been replaced.
  13. Marre, Klaus (2016-10-05). "Guantanamo Bay's (other) dirty secret". Who What Why. Retrieved 2016-10-15.
  14. Fallon, Mark (2014-12-08). "Dick Cheney Was Lying About Torture". Politico. Retrieved 2016-10-15. The self-defeating stupidity of torture might come as news to Americans who've heard again and again from Cheney and other political leaders that torture "worked." Professional interrogators, however, couldn't be less surprised. We know that legal, rapport-building interrogation techniques are the best way to obtain intelligence, and that torture tends to solicit unreliable information that sets back investigations.
  15. "New Guantanamo Intelligence Upends Old 'Worst of the Worst' Myths". Military.com. 2016-10-07. Retrieved 2016-10-15. 'It was clear early on that the intelligence was grossly wrong,' said Mark Fallon, a retired 30-year federal officer who between 2002 and 2004 was Special Agent in Charge of the Department of Defense's Criminal Investigation Task Force. Most 'weren't battlefield captives,' he said, calling many 'bounty babies' -- men captured by Afghan warlords or Pakistani security forces and sent to Guantanamo 'on the sketchiest bit of intelligence with nothing to corroborate.'
  16. dev_admin (2008-02-23). "Mark Fallon Joins The Soufan Group". The Soufan Group. Retrieved 2026-07-14.
  17. "Mark Fallon Joins The Soufan Group". Soufan Group. 2008-02-23. Retrieved 2016-10-15.
  18. Landay, Jonathan (2017-08-03). "An ex-Gitmo employee says the Pentagon is suppressing his book on 'torture'". Business Insider. Retrieved 2019-10-05. Darrell Walker, chief of the Defense Office of Prepublication and Security Review, denied blocking Fallon's book. The delay, he said, is the result of 10 federal agencies having to scrub the manuscript. Two have yet to complete their assessments, including one outside the Defense Department, which he did not identify.
  19. "CERL - Center for Ethics and the Rule of Law". Retrieved 2026-07-14.
  20. Seigel, Jessica (25 March 2021). "The truth about lying". Knowable Magazine. doi:10.1146/knowable-032421-1. Retrieved 8 December 2021.
  21. Méndez, Juan E. (August 2016). "UN Docs A/71/298". undocs.org. Retrieved 2024-05-20
  22. Méndez, Juan E.; Drummond, Vanessa (2021-06-01). "The Méndez Principles: A New Standard for Effective Interviewing by Police and Others, While Respecting Human Rights". Just Security. Retrieved 2024-05-20.
  23. Barela, Steven J.; Fallon, Mark (2021-06-01). "The Méndez Principles: Leadership to Transform Interrogation via Science, Law, and Ethics". Just Security. Retrieved 2024-05-20.
  24. Savage, Charlie (2019-04-02). "Ex-National Security Officials Sue to Limit Censorship of Their Books". The New York Times. ISSN 0362-4331. Retrieved 2026-07-14.
  25. "If Trump wants waterboarding, this could be why". Christian Science Monitor. ISSN 0882-7729. Retrieved 2026-07-14.
  26. Fallon, Mark (2017-10-24). Unjustifiable Means: The Inside Story of How the CIA, Pentagon, and US Government Conspired to Torture. Simon and Schuster. ISBN 978-1-942872-79-5.
  27. "Turning Point: 9/11 and the Global War on Terror". www.imdb.com. Retrieved 2026-07-14.
  28. "Eminent Monsters". www.imdb.com. Retrieved 2026-07-14.
  29. "The Interrogation Tapes". www.imdb.com. Retrieved 2026-07-14.
  30. Vanity Fair (2021-11-01). Former Special Agent Reviews Interrogations From Movies & TV | Vanity Fair. Retrieved 2026-07-14 – via YouTube.
  31. "Inside the Real NCIS". www.imdb.com. Retrieved 2026-07-14.
  32. "Seconds from Disaster – Cable Car Collision". www.imdb.com. Retrieved 2026-07-14.
  33. Leaving Hotel California (2026-06-12). Leaving Hotel California | Official Trailer. Retrieved 2026-07-14 – via YouTube.