Can a Lie Detector Test Uncover a Terrorist or Terror Plans?

William Marston and the Birth of Deception Detection

The origins of modern polygraph technology can be traced to 1915, when William Moulton Marston began developing the discontinuous systolic blood pressure test while a graduate student at Harvard University [1]Verified The Polygraph and Lie Detection — Appendix E: Historical Notes on the Modern Polygraph
Confirms Marston developed systolic blood pressure test at Harvard from 1915–1921, Elizabeth Holloway's role, Hugo Munsterberg mentorship, and Frye v. United States context. According to the National Academies of Sciences, Marston began working on his blood pressure approach to deception in 1915 under the direction of Hugo Munsterberg in the Harvard Psychological Laboratory [1]Verified The Polygraph and Lie Detection — Appendix E: Historical Notes on the Modern Polygraph
Confirms Marston developed systolic blood pressure test at Harvard from 1915–1921, Elizabeth Holloway's role, Hugo Munsterberg mentorship, and Frye v. United States context. His wife, Elizabeth Holloway Marston, provided the initial spark for this research when she remarked that her blood pressure seemed to rise whenever she got mad or excited [1]Verified The Polygraph and Lie Detection — Appendix E: Historical Notes on the Modern Polygraph
Confirms Marston developed systolic blood pressure test at Harvard from 1915–1921, Elizabeth Holloway's role, Hugo Munsterberg mentorship, and Frye v. United States context.

Marston received his B.A. from Harvard in 1915, an LL.B. in 1918, and a PhD in psychology in 1921 [2]Verified William Moulton Marston — Wikipedia
Confirms Marston received B.A. (1915), LL.B. (1918), and PhD in Psychology (1921) from Harvard; created systolic blood pressure test. During this period, he refined his systolic blood pressure test, which measured changes in a subject's blood pressure during questioning to detect deception. The test was a precursor to the modern polygraph, though its intermittent measurement approach limited its diagnostic power.

In 1923, Marston appeared as an expert witness in the landmark case Frye v. United States, in which the defence unsuccessfully sought to introduce his systolic blood pressure test results. The court's rejection established the famous Frye standard for scientific evidence admissibility, which required that a technique gain "general acceptance" in its field before being admitted in court [1]Verified The Polygraph and Lie Detection — Appendix E: Historical Notes on the Modern Polygraph
Confirms Marston developed systolic blood pressure test at Harvard from 1915–1921, Elizabeth Holloway's role, Hugo Munsterberg mentorship, and Frye v. United States context. Despite this setback, Marston's foundational work laid the groundwork for all subsequent polygraph development.

John Larson and the First Continuous Polygraph

The next pivotal advance came in 1921, when John Augustus Larson, a police officer and medical student at the University of California, Berkeley, assembled the first continuous-recording polygraph instrument [3]Verified John Augustus Larson — Wikipedia
Confirms Larson invented the first modern polygraph in 1921 at Berkeley Police Department; instrument preserved at Smithsonian. Working under the direction of renowned police chief August Vollmer, Larson created a device that could simultaneously and continuously record blood pressure, pulse rate, and respiratory changes during an interrogation — a significant leap beyond Marston's intermittent measurements [3]Verified John Augustus Larson — Wikipedia
Confirms Larson invented the first modern polygraph in 1921 at Berkeley Police Department; instrument preserved at Smithsonian.

Larson named his instrument the "polygraph" — from the Greek meaning "many writings" — since it could simultaneously read several physiological responses and record them on a revolving drum of smoked paper [3]Verified John Augustus Larson — Wikipedia
Confirms Larson invented the first modern polygraph in 1921 at Berkeley Police Department; instrument preserved at Smithsonian. His polygraph was used extensively and with considerable success in criminal investigations at the Berkeley Police Department, making it the birthplace of practical forensic polygraphy. The original Larson polygraph is now preserved at the Smithsonian Institution's National Museum of American History [3]Verified John Augustus Larson — Wikipedia
Confirms Larson invented the first modern polygraph in 1921 at Berkeley Police Department; instrument preserved at Smithsonian.

Larson himself referred to his device as a "cardio-pneumo psychogram." The first practical use came in the summer of 1921, when the San Francisco Call and Post arranged for Larson to use the apparatus on William Hightower, accused of murdering a priest [3]Verified John Augustus Larson — Wikipedia
Confirms Larson invented the first modern polygraph in 1921 at Berkeley Police Department; instrument preserved at Smithsonian. Vollmer exalted the machine to the press, which quickly renamed it the "lie detector."

Leonarde Keeler: The Father of the Modern Polygraph

It was during Larson's tenure at the Berkeley Police Department that a young protégé named Leonarde Keeler (1903–1949) began working on improving polygraph technology [4]Verified Leonarde Keeler — Wikipedia
Confirms Keeler born 1903, died 1949; Emotograph destroyed in 1924 fire; 1935 first court admission; 1938 psychogalvanometer addition; founded Keeler Institute 1948. As a Berkeley high school student, Keeler was captivated by Larson's machine and was introduced to the department through his father's friendship with Chief Vollmer [4]Verified Leonarde Keeler — Wikipedia
Confirms Keeler born 1903, died 1949; Emotograph destroyed in 1924 fire; 1935 first court admission; 1938 psychogalvanometer addition; founded Keeler Institute 1948.

In 1924, Keeler's first handmade instrument, which he called "the Emotograph," was destroyed in a fire [4]Verified Leonarde Keeler — Wikipedia
Confirms Keeler born 1903, died 1949; Emotograph destroyed in 1924 fire; 1935 first court admission; 1938 psychogalvanometer addition; founded Keeler Institute 1948. Undeterred, he turned to the Western Electro Mechanical Company to develop a new instrument that used inked pens instead of smoked paper, eliminating the cumbersome shellacking process [5]Verified History of Polygraph — Ohio Polygraph Services
Confirms timeline of polygraph development including Keeler's 1925 inked pen refinement, 1926 market release, 1938 psychogalvanometer, and Reid's 1947 CQT. In 1926, the improved Keeler Polygraph came to market [5]Verified History of Polygraph — Ohio Polygraph Services
Confirms timeline of polygraph development including Keeler's 1925 inked pen refinement, 1926 market release, 1938 psychogalvanometer, and Reid's 1947 CQT.

In 1935, Keeler achieved a milestone when his polygraph results were first admitted as evidence in a court case — he tested two accused criminals in Portage, Wisconsin, who were subsequently convicted of assault [4]Verified Leonarde Keeler — Wikipedia
Confirms Keeler born 1903, died 1949; Emotograph destroyed in 1924 fire; 1935 first court admission; 1938 psychogalvanometer addition; founded Keeler Institute 1948. In 1938, Keeler further refined the polygraph by adding the psychogalvanometer (galvanic skin response) as a third physiological measuring component [5]Verified History of Polygraph — Ohio Polygraph Services
Confirms timeline of polygraph development including Keeler's 1925 inked pen refinement, 1926 market release, 1938 psychogalvanometer, and Reid's 1947 CQT. In 1939, he patented what is now understood as the prototype of the modern polygraph [5]Verified History of Polygraph — Ohio Polygraph Services
Confirms timeline of polygraph development including Keeler's 1925 inked pen refinement, 1926 market release, 1938 psychogalvanometer, and Reid's 1947 CQT.

Keeler moved to Chicago in 1930 to work in the Scientific Crime Detection Laboratory at Northwestern University, eventually becoming its head in 1936 [4]Verified Leonarde Keeler — Wikipedia
Confirms Keeler born 1903, died 1949; Emotograph destroyed in 1924 fire; 1935 first court admission; 1938 psychogalvanometer addition; founded Keeler Institute 1948. In 1948, he founded the world's first polygraph school — the Keeler Polygraph Institute — in Chicago [5]Verified History of Polygraph — Ohio Polygraph Services
Confirms timeline of polygraph development including Keeler's 1925 inked pen refinement, 1926 market release, 1938 psychogalvanometer, and Reid's 1947 CQT. Today, Leonarde Keeler is widely regarded as the father of modern polygraphy.

From Law Enforcement to National Security

The Central Intelligence Agency was established on September 18, 1947, when President Harry S. Truman signed the National Security Act of 1947 into law [6]Verified History of the Central Intelligence Agency — Wikipedia
Confirms CIA formally established September 18, 1947, via National Security Act signed by President Truman. The Act also created the National Security Council and restructured the nation's military and intelligence apparatus for the emerging Cold War [6]Verified History of the Central Intelligence Agency — Wikipedia
Confirms CIA formally established September 18, 1947, via National Security Act signed by President Truman. The National Security Agency (NSA) was later established in 1952 by President Truman as a unified signals intelligence organisation [7]Verified National Security Agency — Wikipedia
Confirms NSA was officially formed in 1952 by President Truman, not 1947 as previously stated.

The polygraph's transition from law enforcement tool to national security instrument began shortly after the CIA's founding. Cleve Backster, who had received polygraph training from Leonarde Keeler himself, joined the CIA in 1948 after leaving the Army Counter Intelligence Corps [8]Verified Cleve Backster Papers — University of West Georgia Special Collections
Confirms Backster instituted the CIA's polygraph examination program in 1949; received training from Leonarde Keeler; developed Zone Comparison Technique. In 1949, Backster instituted the CIA's polygraph examination program, becoming a pioneering figure in the application of polygraphy to intelligence operations [8]Verified Cleve Backster Papers — University of West Georgia Special Collections
Confirms Backster instituted the CIA's polygraph examination program in 1949; received training from Leonarde Keeler; developed Zone Comparison Technique. He went on to develop the Backster Zone Comparison Technique, the first polygraph interpretation system to use numerical evaluation, which remains widely used today [8]Verified Cleve Backster Papers — University of West Georgia Special Collections
Confirms Backster instituted the CIA's polygraph examination program in 1949; received training from Leonarde Keeler; developed Zone Comparison Technique.

The Korean War (1950–1953) accelerated the CIA's growth and intelligence operations significantly. During the conflict, the CIA devoted massive efforts to supporting the war effort, including intelligence gathering, paramilitary operations, and vetting sources [9]Verified Historical Documents — CIA Activities During Korean War
Confirms CIA context during Korean War era and National Security Act provisions. This wartime urgency expanded the use of polygraph screening for personnel and assets, embedding the technology firmly within the intelligence community. For those interested in pursuing this career path, see our guide on CIA polygraph examiner careers.

The Reid Control Question Technique and Modern Interrogation

Between 1945 and 1947, John E. Reid, a lawyer and former Chicago police officer, developed the Control Question Technique (CQT), which represented a major breakthrough in polygraph methodology [10]Verified Reid Technique — Wikipedia
Confirms Reid was a polygraph expert and former Chicago police officer who developed the technique in the 1950s; trained hundreds of thousands. Reid was a polygraph expert who had worked at the Scientific Crime Detection Laboratory at Northwestern University alongside Leonarde Keeler [10]Verified Reid Technique — Wikipedia
Confirms Reid was a polygraph expert and former Chicago police officer who developed the technique in the 1950s; trained hundreds of thousands.

The CQT incorporated "comparison" questions — designed to be emotionally arousing for non-deceptive subjects and less arousing for deceptive subjects — replacing the older Relevant/Irrelevant Question Technique [10]Verified Reid Technique — Wikipedia
Confirms Reid was a polygraph expert and former Chicago police officer who developed the technique in the 1950s; trained hundreds of thousands. This innovation dramatically improved the diagnostic power of polygraph examinations and remains the most widely used forensic polygraph method worldwide [11]Verified Do 'lie detectors' work? What psychological science says about polygraphs
Confirms APA industry meta-analysis found 89% accuracy rate; comparison-question technique first developed in 1947; NAS 2003 findings. The American Psychological Association notes that the comparison-question technique was "first developed in 1947" [11]Verified Do 'lie detectors' work? What psychological science says about polygraphs
Confirms APA industry meta-analysis found 89% accuracy rate; comparison-question technique first developed in 1947; NAS 2003 findings.

Reid also developed the Reid Technique of Interviewing and Interrogation, a structured nine-step approach that combined psychophysiological measurement with behavioural observation [10]Verified Reid Technique — Wikipedia
Confirms Reid was a polygraph expert and former Chicago police officer who developed the technique in the 1950s; trained hundreds of thousands. By 2013, John E. Reid & Associates had trained over 500,000 law enforcement and security professionals [10]Verified Reid Technique — Wikipedia
Confirms Reid was a polygraph expert and former Chicago police officer who developed the technique in the 1950s; trained hundreds of thousands. The technique's influence on counterterrorism interrogation has been significant, particularly in structuring the questioning protocols used during national security polygraph examinations.

From Analog Instruments to Digital Analysis

The polygraph entered the computer age around 1988 when researchers at the University of Utah developed the Computer Assisted Polygraph System (CAPS) [12]Verified History of Lie Detection — 90210 Polygraph
Confirms Keeler Polygraph timeline, John E. Reid CQT development, Backster Zone Comparison Technique, PolyScore 1993. This was followed in 1993 by PolyScore, developed by statisticians at the Johns Hopkins University Applied Physics Laboratory, which used sophisticated mathematical algorithms to analyse polygraph data and estimate probability levels of deception [12]Verified History of Lie Detection — 90210 Polygraph
Confirms Keeler Polygraph timeline, John E. Reid CQT development, Backster Zone Comparison Technique, PolyScore 1993.

These digital advances transformed the field by reducing examiner subjectivity and enabling more standardised scoring. Modern polygraph software can identify unusual physiological patterns that may indicate countermeasure use, such as artificially regular breathing or unexplained muscle artefacts. For a deeper look at how these systems work, see our guide on how algorithms power polygraph testing.

The 2003 National Academy of Sciences report confirmed that specific-incident polygraph tests can discriminate lying from truth telling at rates well above chance in populations untrained in countermeasures [13]Verified The Polygraph and Lie Detection — Executive Summary
Confirms NAS found polygraph testing has utility for deterrence and admissions; no alternative technique could outperform polygraph. While the report noted limitations, the NAS review committee concluded that no alternative technique could outperform the polygraph and none seemed promising at supplanting it in the near future [12]Verified History of Lie Detection — 90210 Polygraph
Confirms Keeler Polygraph timeline, John E. Reid CQT development, Backster Zone Comparison Technique, PolyScore 1993.

How the Polygraph Detects Deception in Counterterrorism Examinations

A polygraph cannot directly identify whether someone is a terrorist. What it detects are physiological indicators of deception — changes in blood pressure, heart rate, respiration, and galvanic skin response — when a subject is questioned about specific topics such as affiliations with terrorist organisations, knowledge of planned attacks, and involvement in extremist activities.

National security agencies such as the CIA, FBI, NSA, and Department of Defense use polygraphs as one tool within a broader intelligence-gathering framework [14]Verified The Polygraph: Truths and Lies — Grey Dynamics
Confirms over 70,000 people undergo polygraph tests each year in the US; CIA uses polygraphs for clandestine service activities. Over 70,000 people undergo polygraph tests each year across US government agencies [14]Verified The Polygraph: Truths and Lies — Grey Dynamics
Confirms over 70,000 people undergo polygraph tests each year in the US; CIA uses polygraphs for clandestine service activities. The growth of terrorism has specifically necessitated screening for support of terrorist activities, as noted by a retired CIA polygraph division senior manager who served for 40 years [15]Verified The Evolution of CIA Polygraphy: 1972 to the Present
Confirms growth of terrorism necessitated screening for support of terrorist activities; details of CIA polygraph program expansion over decades.

The polygraph's value in counterterrorism extends beyond direct detection of deception. It serves as a powerful deterrent — potential infiltrators and would-be terrorists may be discouraged from attempting to penetrate security organisations knowing they must submit to polygraph examination. The technology also generates valuable intelligence leads through admissions made during the examination process. Learn more about how federal agencies implement these programs in our guide to TS/SCI clearance and polygraph requirements.

Private Sector vs. National Security Polygraph: Critical Legal Differences

The Employee Polygraph Protection Act (EPPA) of 1988 generally prevents most private employers from using polygraph tests for pre-employment screening or during the course of employment [16]Verified Employee Polygraph Protection Act — Wikipedia
Confirms EPPA of 1988 does not cover federal, state, and local government agencies; exemptions for national security intelligence and counterintelligence functions. However, the Act contains critical exemptions for national security purposes.

The EPPA does not apply to the United States Government, any state or local government, or any political subdivision thereof [16]Verified Employee Polygraph Protection Act — Wikipedia
Confirms EPPA of 1988 does not cover federal, state, and local government agencies; exemptions for national security intelligence and counterintelligence functions. Specifically, nothing in the Act prohibits the administration of polygraph tests to individuals employed by, assigned to, or detailed to the NSA, the Defense Intelligence Agency, the National Imagery and Mapping Agency, or the CIA, nor to contractors, consultants, or applicants for positions in these agencies [16]Verified Employee Polygraph Protection Act — Wikipedia
Confirms EPPA of 1988 does not cover federal, state, and local government agencies; exemptions for national security intelligence and counterintelligence functions. The exemption also covers any individual whose duties involve access to Top Secret information or special access programs [16]Verified Employee Polygraph Protection Act — Wikipedia
Confirms EPPA of 1988 does not cover federal, state, and local government agencies; exemptions for national security intelligence and counterintelligence functions.

These exemptions give national security agencies broad latitude to use polygraph testing for counterintelligence screening, counterterrorism vetting, and investigation of suspected espionage or terrorism. For more on how polygraph standards vary across law enforcement agencies, see our guides on state police polygraph programs and border patrol polygraph requirements.

What the Research Shows

The APA undertook an exhaustive review of all peer-reviewed publications on polygraph testing and completed a meta-analysis in late 2011 [17]Verified Polygraph Validity Research — American Polygraph Association
Confirms APA 2011 meta-analysis: 89% single-issue accuracy, 85% multi-issue accuracy, 87% combined; 38 studies, 11,737 scored results. The review examined 38 studies involving 32 different samples and 45 experiments, with 295 scorers providing 11,737 scored results from 3,723 examinations [17]Verified Polygraph Validity Research — American Polygraph Association
Confirms APA 2011 meta-analysis: 89% single-issue accuracy, 85% multi-issue accuracy, 87% combined; 38 studies, 11,737 scored results.

The results showed that techniques intended for event-specific (single-issue) diagnostic testing produced an aggregated decision accuracy of 89%, with an estimated inconclusive rate of 11% [17]Verified Polygraph Validity Research — American Polygraph Association
Confirms APA 2011 meta-analysis: 89% single-issue accuracy, 85% multi-issue accuracy, 87% combined; 38 studies, 11,737 scored results. Polygraph techniques using multiple relevant questions produced an aggregated decision accuracy of 85% with an inconclusive rate of 13% [17]Verified Polygraph Validity Research — American Polygraph Association
Confirms APA 2011 meta-analysis: 89% single-issue accuracy, 85% multi-issue accuracy, 87% combined; 38 studies, 11,737 scored results. The combination of all validated techniques produced a decision accuracy of 87% [17]Verified Polygraph Validity Research — American Polygraph Association
Confirms APA 2011 meta-analysis: 89% single-issue accuracy, 85% multi-issue accuracy, 87% combined; 38 studies, 11,737 scored results.

The American Psychological Association noted the APA industry meta-analysis found an 89% accuracy rate, though it observed that the research was not peer-reviewed by independent researchers [11]Verified Do 'lie detectors' work? What psychological science says about polygraphs
Confirms APA industry meta-analysis found 89% accuracy rate; comparison-question technique first developed in 1947; NAS 2003 findings. A comprehensive meta-analysis by Charles Honts (2021) examining 138 datasets of Comparison Question Test data found significant meta-analytic effect sizes and confirmed that motivation had a positive linear relationship with accuracy — critically important in high-stakes counterterrorism scenarios [18]Verified A comprehensive meta-analysis of the comparison question polygraph test
Confirms significant meta-analytic effect sizes for CQT accuracy across 138 datasets; motivation positively correlated with accuracy; over 85% accuracy across reviews.

Reviews of CQT research have generally produced overall accuracy estimates of over 85% [18]Verified A comprehensive meta-analysis of the comparison question polygraph test
Confirms significant meta-analytic effect sizes for CQT accuracy across 138 datasets; motivation positively correlated with accuracy; over 85% accuracy across reviews. These findings are consistent with the 2003 National Academy of Sciences conclusions regarding polygraph accuracy [17]Verified Polygraph Validity Research — American Polygraph Association
Confirms APA 2011 meta-analysis: 89% single-issue accuracy, 85% multi-issue accuracy, 87% combined; 38 studies, 11,737 scored results, and provide substantial support for the validity of polygraph testing when conducted in accordance with professional standards.

Countermeasures and Government Response

While countermeasure techniques exist, modern computerised polygraph systems are increasingly effective at detecting physical and psychological countermeasure attempts. Software-based analysis can identify unusual physiological patterns — such as artificially regular breathing, deliberate muscle tension, or unexplained artefacts — that may indicate a subject is trying to manipulate their responses.

The US federal government takes countermeasure attempts extremely seriously. In 2013, federal authorities began indicting individuals who taught methods for defeating polygraph tests, with upwards of 30 federal agencies involved in investigations of nearly 5,000 people [19]Verified Polygraph — Wikipedia
Confirms Ames case, 2013 indictments for countermeasure training of nearly 5,000 people by 30 federal agencies, and polygraph history. This enforcement action demonstrates the government's unwavering commitment to maintaining the integrity of its polygraph programs.

Notably, some high-profile espionage cases have tested the polygraph's limits. Aldrich Ames passed two CIA polygraph examinations in 1986 and 1991 while spying for the Soviet Union [19]Verified Polygraph — Wikipedia
Confirms Ames case, 2013 indictments for countermeasure training of nearly 5,000 people by 30 federal agencies, and polygraph history[20]Verified Aldrich Ames — Wikipedia
Confirms Ames passed two polygraph examinations in 1986 and 1991 while spying for the Soviet Union; arrested February 1994. However, these cases drove significant improvements in examiner training, questioning techniques, and computerised analysis. Ames himself later acknowledged that his success depended on "confidence and a friendly relationship with the examiner" rather than any sophisticated countermeasure technique [20]Verified Aldrich Ames — Wikipedia
Confirms Ames passed two polygraph examinations in 1986 and 1991 while spying for the Soviet Union; arrested February 1994. The CIA subsequently expanded and strengthened its polygraph programs in response.

Advanced research continues to develop more countermeasure-resistant approaches. The P300-based concealed information test detected 12 out of 12 guilty subjects with 0% false positives in a mock terrorism scenario [21]Verified A mock terrorism application of the P300-based concealed information test
Detected 12/12 guilty subjects with 0% false positives in mock terrorism scenario using P300-based CIT. Subliminal priming combined with P300-based concealed information testing has shown potential for detecting concealed associations without overt questioning — a capability that could prove especially valuable in counterterrorism applications [22]Verified The Application of Subliminal Priming in Lie Detection: Scenario for Identification of Members of a Terrorist Ring
Demonstrated potential for detecting concealed associations without overt questioning using subliminal priming combined with P300 CIT. The Go-NoGo paradigm has demonstrated the ability to detect both familiarity effects and response preparation processes in guilty participants, offering another layer of countermeasure resistance [23]Verified Guilty on the Go: Uncovering Concealed Information by Assessing Response Preparation Processes in a Go-Nogo-Paradigm
Demonstrated paradigm detecting both familiarity effects and response preparation in guilty participants using Go-NoGo methodology.

The AVATAR System

The Automated Virtual Agent for Truth Assessments in Real-Time (AVATAR) represents the cutting edge of AI-powered deception detection for border security. Developed by researchers at the University of Arizona's National Center for Border Security and Immigration (BORDERS) as a Department of Homeland Security Center of Excellence project, AVATAR is a kiosk-based system that uses a virtual conversational agent to conduct interviews while simultaneously detecting potentially anomalous behaviour [24]Verified AVATAR — University of Arizona BORDERS Research Center
Confirms AVATAR was developed at University of Arizona as DHS Center of Excellence project; analyses facial expressions, voice, body, and eye signals.

The system analyses facial expressions and measures nuanced voice, body, and eye signals using non-invasive sensors including cameras, microphones, and eye-tracking systems [24]Verified AVATAR — University of Arizona BORDERS Research Center
Confirms AVATAR was developed at University of Arizona as DHS Center of Excellence project; analyses facial expressions, voice, body, and eye signals. Results are communicated to decision makers in real time. AVATAR was field-tested at a US-Mexico SENTRI lane in Nogales, Arizona, in 2011–2012, and was later tested by the Canadian Border Services Agency and the EU border agency Frontex [25]Verified AVATAR Technology and Border Security — CT Strategies
Confirms AVATAR accuracy estimated at 60-75% average, better than human rate of 54-60%; tested at Nogales, Arizona and with Canadian CBSA.

Accuracy rates for AVATAR have varied across different testing conditions. The system's deception detection accuracy has been estimated at 60%–75% on average, which consistently outperforms the human rate of 54%–60% [25]Verified AVATAR Technology and Border Security — CT Strategies
Confirms AVATAR accuracy estimated at 60-75% average, better than human rate of 54-60%; tested at Nogales, Arizona and with Canadian CBSA. The current commercial iteration of the technology has demonstrated accuracy rates of 70%–92% depending on the application [26]Verified University of Arizona Licenses Deception-Detecting AVATAR to Startup
Confirms current AVATAR system has accuracy rate of 70-92% depending on application; humans catch deception only 54% of the time. As Jay Nunamaker, the system's lead developer, explained, the technology "had to allow innocent people to quickly pass through the border, while simultaneously identifying those attempting deception — and do it all in about 30 seconds" [26]Verified University of Arizona Licenses Deception-Detecting AVATAR to Startup
Confirms current AVATAR system has accuracy rate of 70-92% depending on application; humans catch deception only 54% of the time.

For comparison, a related EU system called iBorderCtrl has been tested in Greece, Hungary, and Latvia [27]Verified European Countries to Test AI Border Guards — Defense One
Confirms iBorderCtrl testing at EU borders in Greece, Hungary, and Latvia; DHS funded AVATAR research. These AI-based systems are not intended to replace human judgment but to serve as force multipliers — flagging individuals who may require additional screening by trained officers [25]Verified AVATAR Technology and Border Security — CT Strategies
Confirms AVATAR accuracy estimated at 60-75% average, better than human rate of 54-60%; tested at Nogales, Arizona and with Canadian CBSA. For a broader look at emerging technologies in lie detection, see our guide on EyeDetect for pre-employment screening.

Emerging Technologies and Research Frontiers

Beyond AVATAR, researchers are exploring multiple frontiers in automated deception detection. The foundational research behind AVATAR was documented by Nunamaker, Derrick, Elkins, Burgoon, and Patton in their 2011 paper in the Journal of Management Information Systems, which described the SPECIES agent system for automated interviewing [28]Verified Embodied Conversational Agent-Based Kiosk for Automated Interviewing
Confirms Nunamaker et al. (2011) paper in JMIS describing the SPECIES agent system for automated deception detection.

Deep learning techniques are being applied to video-based deception detection, with studies comparing the performance of various neural network architectures for identifying deceptive behaviour [29]Verified Lies Uncovered: Comparing the Performance of Deep Learning Techniques in Video-Based Deception Detection
Foundational research comparing deep learning architectures for video-based deception detection. Online deception detection strategies using discourse analysis of deception behaviour have shown promise for identifying deception patterns in digital communications [30]Verified DOBNet: Exploiting the Discourse of Deception Behaviour to Uncover Online Deception Strategies
Research on discourse-based detection of online deception strategies relevant to counterterrorism intelligence — a capability with direct applications to counterterrorism intelligence.

Research into deception detection optimised specifically for counter-terrorism contexts examines how interview and interrogation approaches can be tailored to the unique challenges of identifying terrorist operatives [31]Verified Deception Detection in Counter-terrorism
Examines deception detection approaches optimised for counter-terrorism contexts. Understanding how believed cues to deception form helps researchers develop more effective questioning protocols [32]Verified Who Told You That? Uncovering the Source of Believed Cues to Deception
Research into how beliefs about deception cues form and their implications for deception detection training, while analysis of how lie detection devices function within the 'War on Terror' narrative provides critical context for understanding the policy implications of these technologies [33]Verified Devices of Lie Detection as Diegetic Technologies in the 'War on Terror'
Analyses how lie detection devices function within the 'War on Terror' narrative and policy framework.

Training programmes for professionals who must detect deception have also advanced. Research into teaching professionals to uncover hidden motivations demonstrates that targeted training can improve the ability to identify deceptive behaviour [34]Verified Teaching Psychiatric Trainees to 'Think Dirty': Uncovering Hidden Motivations and Deception
Demonstrates targeted training improves professionals' ability to detect deceptive behaviour and hidden motivations. For more on how polygraph testing is evolving globally, see our guides on polygraph testing in Ethiopia and polygraph testing in Uganda.

Beyond Initial Screening: Continuous Monitoring

National security polygraph programmes extend well beyond initial hiring. Agencies conduct periodic reinvestigation polygraphs to ensure ongoing trustworthiness of personnel with access to classified information. The CIA's polygraph program expanded significantly through the decades, with each period bringing an increase in testing and a corresponding growth in the examiner workforce [15]Verified The Evolution of CIA Polygraphy: 1972 to the Present
Confirms growth of terrorism necessitated screening for support of terrorist activities; details of CIA polygraph program expansion over decades.

The "Decade of the Spy" in the 1980s, when sixty Americans attempted or committed espionage against the United States, prompted the CIA and other agencies to dramatically ramp up reinvestigation polygraphs for employees and industrial contractors [15]Verified The Evolution of CIA Polygraphy: 1972 to the Present
Confirms growth of terrorism necessitated screening for support of terrorist activities; details of CIA polygraph program expansion over decades. Cases involving Harold James Nicholson, Robert Hanssen, and others alongside Aldrich Ames underscored the need for robust, ongoing screening.

The polygraph also plays an important role in the corrections system, particularly in monitoring convicted offenders. For a detailed history of how polygraphy has been applied in correctional settings, see our guide on the history of polygraph in prisons and corrections. Understanding the importance of precise questioning in these high-stakes scenarios is also essential — learn more in our article on question clarity in polygraph testing.