Deception Indicated (DI) Result: What It Means & Next Steps

Definition and Clinical Meaning

Deception Indicated — commonly abbreviated DI — is the formal diagnostic opinion rendered by a polygraph examiner when the analysis of an examinee's physiological data meets or exceeds the threshold associated with deception. In practical terms, DI means that your body's measurable responses during the examination were consistent with the patterns typically observed when someone is being untruthful about the specific issue tested.

A DI result is not a legal verdict, not proof beyond reasonable doubt, and not an infallible declaration. It is a probabilistic assessment — a data-driven opinion that the physiological evidence points toward deception rather than truthfulness [1]Verified Meta-Analytic Survey of Criterion Accuracy of Validated Polygraph Techniques
Confirms 89% accuracy for single-issue tests (CI 83-95%), 85% for multi-issue, 87% overall (CI 80-94%), based on 38 studies and 11,737 scored results. The American Polygraph Association (APA) uses the term "diagnostic opinion" rather than "conclusion" deliberately. This language acknowledges that polygraph testing, like all psychophysiological assessments, operates within a framework of statistical probability rather than absolute certainty.

As described in the Federal Psychophysiological Detection of Deception Examiner Handbook, standardized testing procedures and scoring methods ensure that DI determinations follow documented and validated protocols [3]Verified Federal Psychophysiological Detection of Deception Examiner Handbook
Official policy manual standardizing federal polygraph testing procedures, scoring methods, and quality assurance requirements for FBI, DEA, NSA, CIA, and other agencies. When an examiner calls a result DI, they are saying: "Based on the validated scoring methodology I employed, the data is statistically more consistent with deception than with truthfulness."

How Examiners Communicate a DI Result

After completing the data analysis, the examiner will typically communicate the result during the post-test phase of the examination. The language varies between examiners, but you might hear phrases like: "The charts indicate deception on the relevant questions," "Your physiological responses were significant to the relevant questions," or "I am calling this examination Deception Indicated."

A professional, APA-compliant examiner will not say "you failed" or "you're a liar." The examiner reports what the data shows, not who you are as a person. If an examiner uses accusatory or judgmental language, that may be a violation of professional codes of ethics. You can learn more about professional conduct standards in our guide on whether you can trust the polygraph examiner.

If you have recently received a DI result, understanding the examination process is essential. Our complete pre-polygraph preparation guide can help you prepare for any retesting opportunity.

Understanding the Triad: DI, NDI, and Inconclusive

Every properly conducted polygraph examination produces one of exactly three diagnostic opinions. Understanding all three helps contextualize what a DI result means relative to the alternatives.

Deception Indicated (DI): The examinee's physiological responses to relevant questions produced a negative numerical score that meets or exceeds the established threshold. The data is statistically consistent with deception.

No Deception Indicated (NDI): The examinee's physiological responses produced a positive numerical score at or above the truthful threshold. The data is statistically consistent with truthfulness.

Inconclusive (INC): The examinee's physiological responses produced a score that falls between the DI and NDI thresholds. The data is insufficient to render a definitive diagnostic opinion in either direction. The APA's 2011 meta-analysis found inconclusive rates of approximately 11% for single-issue diagnostic tests and 13% for multi-issue tests [1]Verified Meta-Analytic Survey of Criterion Accuracy of Validated Polygraph Techniques
Confirms 89% accuracy for single-issue tests (CI 83-95%), 85% for multi-issue, 87% overall (CI 80-94%), based on 38 studies and 11,737 scored results.

This three-outcome system is fundamentally different from a simple pass/fail binary. The existence of the Inconclusive category reflects an honest acknowledgment that physiological data does not always produce a clear signal — a strength of the system that avoids forcing examiners to make a call when the evidence is ambiguous.

In single-issue specific-incident examinations (such as a theft investigation or infidelity test), the data tends to be clearer and inconclusive rates are lower. In multi-issue screening examinations (such as pre-employment testing), the broader scope of questioning can produce higher inconclusive rates [1]Verified Meta-Analytic Survey of Criterion Accuracy of Validated Polygraph Techniques
Confirms 89% accuracy for single-issue tests (CI 83-95%), 85% for multi-issue, 87% overall (CI 80-94%), based on 38 studies and 11,737 scored results.

Numerical Scoring Systems

Modern polygraph scoring is fundamentally a numerical process. The examiner compares physiological responses to relevant questions against responses to comparison questions. Each comparison across each chart produces a numerical score.

There are two primary manual scoring scales approved by the APA:

3-Position Scale: Each comparison point is scored as +1 (response greater to comparison), 0 (no significant difference), or -1 (response greater to relevant). This is simpler but less granular. Research has shown that three-position scoring methods consistently exceeded boundary requirements for inconclusive rates [1]Verified Meta-Analytic Survey of Criterion Accuracy of Validated Polygraph Techniques
Confirms 89% accuracy for single-issue tests (CI 83-95%), 85% for multi-issue, 87% overall (CI 80-94%), based on 38 studies and 11,737 scored results.

7-Position Scale: Scores range from +3 to -3 for each comparison point, allowing for finer differentiation of response magnitude [4]Verified Fundamentals of Polygraph Practice
Confirms publication by Academic Press (Elsevier) in 2015, covering 7-position scoring techniques, data analysis, and evidence-based polygraph practices. As described in Fundamentals of Polygraph Practice by Krapohl and Shaw, for respiration, electrodermal activity, relative blood pressure, and peripheral vasomotor activity, a score from +3 to -3 is assigned for each presentation of a relevant question [4]Verified Fundamentals of Polygraph Practice
Confirms publication by Academic Press (Elsevier) in 2015, covering 7-position scoring techniques, data analysis, and evidence-based polygraph practices.

The scores from all comparison points across all charts (typically 3 to 5 chart presentations) are summed to produce a grand total score. The diagnostic opinion depends on where this grand total falls relative to pre-established thresholds.

DI Scoring Thresholds by Technique

Different validated techniques use slightly different cutoff scores, but the general framework is consistent:

Utah Zone Comparison Test (UZCT): Using the 7-position scale, a DI threshold is typically a grand total of -6 or below. NDI threshold is +6 or above. Scores between -5 and +5 are Inconclusive.

Federal Zone Comparison Test (FZCT): Similar thresholds to the UZCT. A cumulative score of -6 or lower across all charts triggers a DI call. This technique is widely used in U.S. federal agency testing, as documented in the Federal Psychophysiological Detection of Deception Examiner Handbook [3]Verified Federal Psychophysiological Detection of Deception Examiner Handbook
Official policy manual standardizing federal polygraph testing procedures, scoring methods, and quality assurance requirements for FBI, DEA, NSA, CIA, and other agencies.

Directed Lie Screening Test (DLST): Screening tests often use adjusted thresholds to balance sensitivity and specificity for the screening population. DI cutoffs may range from -4 to -6 depending on the specific protocol.

The important takeaway is that a DI result is never based on a single physiological response or a single chart. It requires a pattern of consistent, significant responses across multiple presentations.

Manual Scoring vs. Computerized Scoring

Most modern polygraph examinations use both manual and computerized approaches. The examiner scores the charts manually using the 7-position scale, and then a computerized algorithm independently scores the same data. When both methods agree, confidence in the diagnostic opinion increases substantially. When they disagree, the examiner must carefully review the data and may call the result Inconclusive. For more on how technology has transformed this process, see our guide on how software changed the lie detector test.

The primary computerized scoring algorithms used in modern practice include:

OSS-3 (Objective Scoring System, Version 3): Developed by Raymond Nelson, Donald Krapohl, and Mark Handler, this open-source algorithm uses a logistic regression formula trained on large datasets of confirmed outcomes [5]Verified Brute-Force Comparison: A Monte Carlo Study of the Objective Scoring System version 3 (OSS-3) and Human Polygraph Scorers
Confirms OSS-3 exceeded human scorer accuracy on multiple dimensions, demonstrated balanced sensitivity/specificity, and provided perfect reliability compared to human inter-rater kappa of approximately.58. It was tested against 292 known single-issue exams and a second dataset of 100 confirmed cases [5]Verified Brute-Force Comparison: A Monte Carlo Study of the Objective Scoring System version 3 (OSS-3) and Human Polygraph Scorers
Confirms OSS-3 exceeded human scorer accuracy on multiple dimensions, demonstrated balanced sensitivity/specificity, and provided perfect reliability compared to human inter-rater kappa of approximately.58. The OSS-3 demonstrated balanced sensitivity and specificity and provided perfect reliability, compared to human inter-rater reliability of approximately k =.58 [5]Verified Brute-Force Comparison: A Monte Carlo Study of the Objective Scoring System version 3 (OSS-3) and Human Polygraph Scorers
Confirms OSS-3 exceeded human scorer accuracy on multiple dimensions, demonstrated balanced sensitivity/specificity, and provided perfect reliability compared to human inter-rater kappa of approximately.58.

PolyScore: Developed at the Johns Hopkins University Applied Physics Laboratory (JHU-APL), this proprietary algorithm uses logistic regression for classification [6]Verified Appendix F: Computerized Scoring of Polygraph Data (The Polygraph and Lie Detection)
Confirms PolyScore developed at JHU-APL using logistic regression, CPS developed at University of Utah using discriminant analysis, and details standardization methods for both systems. The NRC's 2003 report reviewed its development and noted that PolyScore standardizes data by subtracting the median and dividing by the interquartile range [6]Verified Appendix F: Computerized Scoring of Polygraph Data (The Polygraph and Lie Detection)
Confirms PolyScore developed at JHU-APL using logistic regression, CPS developed at University of Utah using discriminant analysis, and details standardization methods for both systems.

CPS (Computerized Polygraph System): Developed at the University of Utah and used in Stoelting's CPS Pro instruments, this algorithm is based on standard multivariate linear discriminant function analysis and produces probability estimates of truthfulness or deception [6]Verified Appendix F: Computerized Scoring of Polygraph Data (The Polygraph and Lie Detection)
Confirms PolyScore developed at JHU-APL using logistic regression, CPS developed at University of Utah using discriminant analysis, and details standardization methods for both systems. It uses features including skin conductance amplitude, cardiograph baseline increases, and respiration line-length measurements [6]Verified Appendix F: Computerized Scoring of Polygraph Data (The Polygraph and Lie Detection)
Confirms PolyScore developed at JHU-APL using logistic regression, CPS developed at University of Utah using discriminant analysis, and details standardization methods for both systems.

Research by Nelson, Krapohl, and Handler (2008) demonstrated that the OSS-3 computer algorithm exceeded the average decision accuracy of human scorers, with perfect reliability compared to human inter-rater variability [5]Verified Brute-Force Comparison: A Monte Carlo Study of the Objective Scoring System version 3 (OSS-3) and Human Polygraph Scorers
Confirms OSS-3 exceeded human scorer accuracy on multiple dimensions, demonstrated balanced sensitivity/specificity, and provided perfect reliability compared to human inter-rater kappa of approximately.58. This hybrid approach — computer-assisted, examiner-driven analysis — represents the modern standard of forensic psychophysiology. Our polygraph instrument comparison chart details which instruments support these algorithms.

What Your Body Does When You Deceive

A polygraph instrument measures multiple physiological channels simultaneously. When a person attempts to deceive, the autonomic nervous system — which operates largely below conscious awareness — produces measurable changes across several systems. These changes are what the polygraph detects and what examiners evaluate to reach a DI determination.

The four primary channels monitored during a standard polygraph examination are:

Respiratory activity (pneumograph): Two pneumatic tubes around the chest and abdomen measure breathing rate, depth, and rhythm. Deception often produces respiratory suppression, irregular breathing patterns, or holding one's breath. The NCCA's numerical scoring guidelines identify specific respiratory features including apnea-blocking, decrease in amplitude, progressive decrease in amplitude, decrease in cyclic rate, and inhalation/exhalation ratio changes [7]Verified NCCA Numerical Scoring Guide
Confirms NCCA respiratory scoring features including RLL methodology, apnea-blocking, and standardized numerical scoring criteria.

Electrodermal activity (EDA): Finger plates or electrodes measure changes in skin conductivity caused by sweat gland activity. This is one of the most sensitive indicators of arousal and is particularly responsive to cognitive stress associated with deception. Research confirms the electrodermal response is "the most robust and informative" of all signals collected during polygraph testing [5]Verified Brute-Force Comparison: A Monte Carlo Study of the Objective Scoring System version 3 (OSS-3) and Human Polygraph Scorers
Confirms OSS-3 exceeded human scorer accuracy on multiple dimensions, demonstrated balanced sensitivity/specificity, and provided perfect reliability compared to human inter-rater kappa of approximately.58.

Cardiovascular activity (cardiograph): A blood pressure cuff measures relative changes in blood pressure, heart rate, and pulse amplitude. Deceptive responses often produce increases in blood pressure and changes in heart rate.

Vasomotor/plethysmograph: A finger pulse sensor measures blood volume changes in the fingertip. This channel provides additional cardiovascular data and is sensitive to sympathetic nervous system activation.

When the examiner asks a relevant question and the examinee's responses across these channels are significantly larger or qualitatively different compared to comparison question responses, those differences accumulate into the negative scores that lead to a DI call. For those curious about what behavior a polygraph examiner looks for, the trained observation of physiological data is central to the process.

The Autonomic Nervous System and the Polygraph

The physiological responses measured by a polygraph are controlled by the autonomic nervous system (ANS), specifically the interplay between the sympathetic nervous system (which activates the "fight-or-flight" response) and the parasympathetic nervous system (which promotes rest and recovery).

When a person knowingly provides a deceptive answer to a question they understand is significant, the brain activates a complex cascade of neural and hormonal responses. The amygdala detects the threat of potential detection, the hypothalamus initiates a stress response, and the sympathetic nervous system produces the measurable changes the polygraph records.

This process is largely involuntary — it happens even when the person is trying to remain calm. As the NRC's 2003 report acknowledged, "psychological states often associated with deception do tend to affect the physiological responses that the polygraph measures" [2]Verified The Polygraph and Lie Detection
Confirms NRC conclusion that polygraph accuracy is 'well above chance, though well below perfection' and that psychological states associated with deception affect physiological responses measured by the polygraph. This is the fundamental premise of polygraph testing: the autonomic responses associated with the cognitive and emotional burden of deception are different from those associated with truthful responding, and those differences can be measured and quantified. Individuals who have anxiety disorders may have specific concerns about how their condition interacts with these measurements.

Recent research has expanded beyond traditional polygraph channels. Studies examining eye-tracking in concealed information tests have shown that deception can also be detected through ocular responses [8]Verified Deception detection by means of eye-tracking in the concealed information test
Foundational research on expanding physiological channels for deception detection beyond traditional polygraph measures using ocular responses. Neural network approaches analyzing physiological responses have achieved 62% deception detection accuracy — exceeding typical human performance of 54% — demonstrating that multiple physiological pathways carry deception-related information [9]Verified Explaining Neural Network Results by Sensitivity Analysis for Deception Detection
Confirms neural networks achieved 62% deception detection accuracy analyzing observer physiological responses, exceeding typical human performance of 54%. Additionally, P300 brainwave research has found a large mean effect size (d* = 1.59) for detecting concealed information across 54 studies, suggesting that EEG and brain-based approaches may complement traditional polygraph methods in the future [10]Verified Decoding Deception with the P300: A Meta-Analysis of the Concealed Information Test
Found large mean effect size (d*=1.59) for P300-based concealed information detection across 54 experimental studies. Technologies like EyeDetect by Converus represent emerging alternatives based on some of these findings.

What the Research Shows

The question everyone asks about a DI result is: "How likely is it to be correct?" The answer depends on the type of examination, the technique used, and the examiner's training. Several major scientific assessments provide the most authoritative data:

National Research Council (NRC) 2003 Report: The NRC reviewed decades of polygraph research and concluded that specific-incident polygraph tests "can discriminate lying from truth telling at rates well above chance, though well below perfection" [2]Verified The Polygraph and Lie Detection
Confirms NRC conclusion that polygraph accuracy is 'well above chance, though well below perfection' and that psychological states associated with deception affect physiological responses measured by the polygraph. The Journal of the American Academy of Psychiatry and the Law characterized the NRC's finding as accuracy "in the region of 81 to 91 percent" [11]Verified The Polygraph and Forensic Psychiatry
Confirms NRC accuracy finding 'in the region of 81 to 91 percent' described as 'well above chance, though well below perfection'. The NRC analyzed 57 laboratory studies and multiple field studies, with seven field studies involving specific incidents revealing a median accuracy of 89% [2]Verified The Polygraph and Lie Detection
Confirms NRC conclusion that polygraph accuracy is 'well above chance, though well below perfection' and that psychological states associated with deception affect physiological responses measured by the polygraph. The American Polygraph Association has stated that "research studies published since 1980 reporting average accuracy rates ranging from 80 to 98 percent" [2]Verified The Polygraph and Lie Detection
Confirms NRC conclusion that polygraph accuracy is 'well above chance, though well below perfection' and that psychological states associated with deception affect physiological responses measured by the polygraph.

APA 2011 Meta-Analysis: The APA commissioned an exhaustive review of all peer-reviewed publications on polygraph testing that met the requirements of the APA Standards of Practice [1]Verified Meta-Analytic Survey of Criterion Accuracy of Validated Polygraph Techniques
Confirms 89% accuracy for single-issue tests (CI 83-95%), 85% for multi-issue, 87% overall (CI 80-94%), based on 38 studies and 11,737 scored results. A total of 38 studies satisfied the qualitative and quantitative requirements for inclusion, involving 32 different samples with 295 scorers who provided 11,737 scored results of 3,723 examinations [1]Verified Meta-Analytic Survey of Criterion Accuracy of Validated Polygraph Techniques
Confirms 89% accuracy for single-issue tests (CI 83-95%), 85% for multi-issue, 87% overall (CI 80-94%), based on 38 studies and 11,737 scored results. The data showed that techniques intended for event-specific (single-issue) diagnostic testing produced an aggregated decision accuracy of 89% (confidence interval 83%–95%), with an estimated inconclusive rate of 11% [1]Verified Meta-Analytic Survey of Criterion Accuracy of Validated Polygraph Techniques
Confirms 89% accuracy for single-issue tests (CI 83-95%), 85% for multi-issue, 87% overall (CI 80-94%), based on 38 studies and 11,737 scored results. Multi-issue techniques produced 85% accuracy (confidence interval 77%–93%) with a 13% inconclusive rate [1]Verified Meta-Analytic Survey of Criterion Accuracy of Validated Polygraph Techniques
Confirms 89% accuracy for single-issue tests (CI 83-95%), 85% for multi-issue, 87% overall (CI 80-94%), based on 38 studies and 11,737 scored results. The combination of all validated techniques produced a decision accuracy of 87% (confidence interval 80%–94%) [1]Verified Meta-Analytic Survey of Criterion Accuracy of Validated Polygraph Techniques
Confirms 89% accuracy for single-issue tests (CI 83-95%), 85% for multi-issue, 87% overall (CI 80-94%), based on 38 studies and 11,737 scored results.

British Psychological Society (BPS) 2004 Report: The BPS conducted an official UK scientific assessment that reviewed the evidence base across multiple polygraph applications and provided recommendations for potential UK adoption, laying groundwork for later UK PCSOT implementation [12]Verified A Review of the Current Scientific Status and Fields of Application of Polygraphic Deception Detection
Official UK scientific assessment by the British Psychological Society reviewing evidence across multiple polygraph applications, providing recommendations for potential UK adoption.

For a deeper exploration of these figures, our comprehensive guide to polygraph accuracy and our analysis on whether polygraph exams are accurate cover the topic in detail.

The Role of Examiner Training

The accuracy of a DI determination is significantly influenced by the quality of examiner training. The National Center for Credibility Assessment (NCCA) — the Department of Defense's education and research organization — trains federal polygraph examiners to standardized protocols [3]Verified Federal Psychophysiological Detection of Deception Examiner Handbook
Official policy manual standardizing federal polygraph testing procedures, scoring methods, and quality assurance requirements for FBI, DEA, NSA, CIA, and other agencies. All federal examiners are expected to have NCCA training per Intelligence Community Policy Guidance 704.6 [3]Verified Federal Psychophysiological Detection of Deception Examiner Handbook
Official policy manual standardizing federal polygraph testing procedures, scoring methods, and quality assurance requirements for FBI, DEA, NSA, CIA, and other agencies.

Research consistently demonstrates that well-trained examiners using validated techniques and standardized scoring methods produce more reliable results. The combination of manual and computerized scoring, as practiced by properly trained professionals, represents the gold standard in the field [5]Verified Brute-Force Comparison: A Monte Carlo Study of the Objective Scoring System version 3 (OSS-3) and Human Polygraph Scorers
Confirms OSS-3 exceeded human scorer accuracy on multiple dimensions, demonstrated balanced sensitivity/specificity, and provided perfect reliability compared to human inter-rater kappa of approximately.58. Examiner training and its impact on polygraph accuracy is one of the most important factors in the reliability of any individual result.

Understanding False Positive Rates

A false positive occurs when a truthful person receives a DI result. This is the most concerning type of error for innocent examinees. Based on the APA's 2011 meta-analysis, single-issue tests achieved 89% decision accuracy with an 11% inconclusive rate [1]Verified Meta-Analytic Survey of Criterion Accuracy of Validated Polygraph Techniques
Confirms 89% accuracy for single-issue tests (CI 83-95%), 85% for multi-issue, 87% overall (CI 80-94%), based on 38 studies and 11,737 scored results. The confidence interval of 83%–95% indicates that in the best-case scenarios, false positive rates for well-conducted single-issue examinations can be very low.

Several factors can contribute to false positive results: high situational anxiety unrelated to deception, medical conditions that affect autonomic function, medications that alter physiological responses, and poor question formulation by the examiner. Importantly, substances like Xanax can affect physiological responses and potentially influence test outcomes.

The NRC's 2003 report emphasized that laboratory studies tend to overestimate accuracy because laboratory conditions involve less variation in test implementation and examinee characteristics than field applications [2]Verified The Polygraph and Lie Detection
Confirms NRC conclusion that polygraph accuracy is 'well above chance, though well below perfection' and that psychological states associated with deception affect physiological responses measured by the polygraph. This is an important consideration when interpreting reported accuracy figures.

Conditions That May Affect Results

Certain physical and psychological conditions can influence polygraph readings. Examinees with anxiety disorders may show heightened baseline arousal, and examiners trained in trauma-informed testing protocols are equipped to account for these factors. Additionally, testing someone who was intoxicated during the incident being investigated raises specific methodological considerations.

Professional examiners conduct thorough pre-test interviews to identify medical conditions, medications, and psychological factors that might affect physiological responses. This pre-test screening is critical to minimizing false positive results. Understanding psychological profiling in polygraph testing helps explain how examiners account for individual differences.

Federal Pre-Employment Screening

For federal agency applicants (FBI, CIA, NSA, CBP, DEA, and others), a DI result typically results in disqualification from the hiring process for that position. Polygraph screening exams are conducted by Intelligence Community agencies that adjudicate SCI and/or SAP eligibility, and a pre-employment polygraph is normally the final hurdle for most applicants.

Most federal agencies do not offer immediate retakes. Customs and Border Protection polygraph results are generally valid for two years, and applicants are eligible to take the polygraph again after that time period. Other agencies have varying policies, though specific waiting periods are not always publicly documented. A failed polygraph at one agency does not necessarily preclude obtaining a security clearance at an agency that does not require polygraph testing.

For detailed information about specific federal agency processes, see our ATF polygraph exam guide.

Criminal Investigations

In criminal cases, a DI result cannot be used as standalone evidence in most jurisdictions. Polygraph test results are generally inadmissible in federal courts and in most state courts. However, statements or admissions made by test subjects during a polygraph session can often be used by prosecutors at trial. A DI finding typically triggers additional investigative steps rather than directly proving guilt.

The admissibility landscape varies significantly by state. Twenty-nine states exclude polygraph results as evidence under any circumstance; fifteen admit the evidence if both parties stipulate to it before testing; and New Mexico permits the routine admission of polygraphs in the courtroom. For state-specific information, our Pennsylvania polygraph admissibility guide and Colorado polygraph law guide provide detailed legal context.

Private Sector Employment

The Employee Polygraph Protection Act of 1988 (EPPA) generally prevents most private employers from using polygraph tests for pre-employment screening or during the course of employment [14]Verified Employee Polygraph Protection Act of 1988
Confirms EPPA prevents most private employers from using polygraph tests and establishes strict procedural safeguards for permitted examinations. Federal, state, and local government agencies are exempted from the Act. Under EPPA, limited exceptions exist for security service firms (armored car, alarm, and guard companies), pharmaceutical manufacturers and distributors, and employers investigating specific workplace incidents involving economic loss [14]Verified Employee Polygraph Protection Act of 1988
Confirms EPPA prevents most private employers from using polygraph tests and establishes strict procedural safeguards for permitted examinations.

Even where polygraph testing is permitted under EPPA, results cannot be used as the sole basis for adverse employment action — additional supporting evidence is required [14]Verified Employee Polygraph Protection Act of 1988
Confirms EPPA prevents most private employers from using polygraph tests and establishes strict procedural safeguards for permitted examinations. The law provides strict procedural safeguards including the right to terminate the test at any time, review all questions before the test, and consult with legal counsel. For more on employer rights regarding polygraph use in New York, see our state-specific guide.

PCSOT (Post-Conviction Sex Offender Testing)

In post-conviction sex offender treatment (PCSOT), DI results are used within the treatment and supervision framework rather than as punitive evidence. A DI finding on a PCSOT examination may indicate that the offender has not been fully forthcoming about behaviors, risk factors, or compliance with supervision conditions.

Therapists and treatment providers work with these results as clinical information to guide treatment direction. Understanding your Fifth Amendment self-incrimination rights in PCSOT is particularly important in this context, as the legal protections differ significantly from other testing scenarios.

Private and Relationship Testing

In private testing contexts — such as infidelity examinations or trust-building tests — a DI result becomes a starting point for conversation rather than a definitive judgment. The examiner will communicate the result and may facilitate initial discussion, but the implications are ultimately a matter for the individuals involved.

Private testing contexts offer the most flexibility in responding to a DI result, including immediate retesting with the same or different examiner. Even unusual scenarios like resolving disputes between flatmates can benefit from understanding the probabilistic nature of DI findings.

Understanding Your Rights

Regardless of the testing context, you have fundamental rights following a DI result:

Right to Understand the Result: The examiner must explain what DI means and how the determination was reached. Under EPPA, examiners must inform employees of test results and allow them an opportunity to explain any reactions [14]Verified Employee Polygraph Protection Act of 1988
Confirms EPPA prevents most private employers from using polygraph tests and establishes strict procedural safeguards for permitted examinations.

Right to Review the Examiner's Report: You are entitled to see the written report of the examination, including the numerical scores, the questions asked, and the examiner's observations.

Right to a Second Opinion: You may seek retesting with a different qualified examiner. This is especially important if you believe the initial result was influenced by anxiety, medical conditions, or procedural issues.

Right to Terminate at Any Time: Under EPPA and APA professional standards, the polygraph examination is voluntary and the examinee can terminate the test at any time [14]Verified Employee Polygraph Protection Act of 1988
Confirms EPPA prevents most private employers from using polygraph tests and establishes strict procedural safeguards for permitted examinations.

Right Against Sole Reliance: In employment contexts covered by EPPA, no adverse employment action can be taken based solely on polygraph results without additional supporting evidence [14]Verified Employee Polygraph Protection Act of 1988
Confirms EPPA prevents most private employers from using polygraph tests and establishes strict procedural safeguards for permitted examinations. Be wary of any examiner or organization that claims guaranteed results — professional standards require honest reporting of diagnostic opinions.

When and How to Seek Retesting

Retesting after a DI result is possible in many contexts, and can be a valuable option for examinees who believe the initial result does not accurately reflect their truthfulness.

In private testing: Retesting is generally available immediately or within a short waiting period, ideally with a different qualified examiner using a validated technique.

In federal employment screening: Agency policies vary. For CBP, polygraph results are generally valid for two years, after which applicants may retest. Other agencies may have different waiting periods, and specific policies are not always publicly documented. Failing a polygraph at one agency does not automatically prevent employment at another.

In criminal investigations: Retesting may be arranged through your attorney, often with a privately retained examiner. Defense attorneys sometimes use polygraph results strategically, though admissibility varies by jurisdiction.

When seeking a retest, choosing a properly trained examiner is critical. Look for APA membership, graduation from an APA-accredited school, and experience with the specific type of test you need. The bait-and-switch problem highlights why verifying examiner credentials matters.

Comparing the Three Outcomes

Understanding how the three outcomes differ helps put a DI result in proper perspective:

Deception Indicated (DI): Grand total score at or below the negative threshold (typically -6). The data suggests deception. Examiner confidence is supported by consistent negative scoring across multiple charts and physiological channels.

No Deception Indicated (NDI): Grand total score at or above the positive threshold (typically +6). The data suggests truthfulness. This is the most favorable outcome, indicating physiological responses were consistent with honest responding.

Inconclusive (INC): Grand total score falls between the thresholds (typically -5 to +5). The data is ambiguous. This outcome represents approximately 11-13% of all examinations depending on the technique used [1]Verified Meta-Analytic Survey of Criterion Accuracy of Validated Polygraph Techniques
Confirms 89% accuracy for single-issue tests (CI 83-95%), 85% for multi-issue, 87% overall (CI 80-94%), based on 38 studies and 11,737 scored results. An inconclusive result is not a failure — it simply means the physiological data was insufficient for a definitive determination.

The critical distinction is that both DI and NDI represent definitive diagnostic opinions with known error rates and statistical confidence intervals, while Inconclusive acknowledges the limits of what the data can support.

Actual Deception

The most straightforward cause of a DI result is actual deception. When an examinee is being untruthful about the specific issue tested, the physiological stress response associated with deception produces the pattern of reactions that leads to a negative score. With single-issue tests achieving 89% decision accuracy [1]Verified Meta-Analytic Survey of Criterion Accuracy of Validated Polygraph Techniques
Confirms 89% accuracy for single-issue tests (CI 83-95%), 85% for multi-issue, 87% overall (CI 80-94%), based on 38 studies and 11,737 scored results, the majority of DI results do reflect genuine deception.

Non-Deceptive Factors

Several factors unrelated to actual deception can produce physiological responses that mimic deceptive patterns:

Anxiety and Fear: High situational anxiety about the test itself can elevate physiological baselines and produce exaggerated responses to relevant questions. This is one of the most commonly cited concerns among examinees.

Medical Conditions: Cardiovascular conditions, respiratory disorders, neurological conditions, and chronic pain can all affect the physiological channels measured during testing.

Medications: Certain medications — particularly those affecting the autonomic nervous system, blood pressure, or heart rate — can alter physiological responses.

Poor Question Construction: If relevant questions are poorly worded, overly broad, or emotionally provocative beyond their investigative purpose, they may elicit strong physiological responses unrelated to deception.

Examiner Conduct: An examiner who creates an unnecessarily threatening or hostile environment may elevate the examinee's stress response throughout the examination, potentially affecting results.

Prior Expectations and Emotional Salience: The NRC noted that "psychological states often associated with deception (e.g., fear of being judged deceptive) do tend to affect the physiological responses that the polygraph measures" — but critically, "these same states can arise in the absence of deception" [2]Verified The Polygraph and Lie Detection
Confirms NRC conclusion that polygraph accuracy is 'well above chance, though well below perfection' and that psychological states associated with deception affect physiological responses measured by the polygraph. This is why the three-outcome system exists: to account for the inherent ambiguity of physiological measurement.