Missouri Consumer Alert: Polygraph Scams & Examiners

No Statewide Licensing Requirement

Unlike states such as Texas, Virginia, or Illinois that maintain robust statewide licensing boards, Missouri has no statewide licensing requirement for polygraph examiners [1]Verified State Licensing Boards & Associations
Confirms Missouri requires polygraph licensing only in St. Louis County; no statewide license needed. According to the American Polygraph Association, a polygraph license is required only in St. Louis County; otherwise, no license is required anywhere else in the state [1]Verified State Licensing Boards & Associations
Confirms Missouri requires polygraph licensing only in St. Louis County; no statewide license needed. This means that outside the St. Louis metropolitan area, virtually anyone can advertise polygraph services without meeting any state-mandated training or certification standards.

The St. Louis County requirement is administered through the St. Louis County Police Department's Professional Licensing Section, located at 7900 Forsyth Boulevard, Clayton, MO 63105 [2]Verified Professional Licensing Manual — St. Louis County Police Department
Confirms St. Louis County licensing procedures for polygraph examiners through the Professional Licensing Section. The licensing program categorizes polygraph examiners alongside watchmen, couriers, and security officers, and licensees are subject to the oversight of the Private Security Coordinator [3]Verified Employee Polygraph Protection Act (EPPA)
Confirms EPPA provisions, employer exemptions, and $10,000 penalty per violation. For a complete breakdown of this county-level requirement, see our guide to Missouri Polygraph Licensing: St. Louis County Requirement.

This regulatory gap is precisely why consumer vigilance is so essential. Without statewide oversight, the burden falls on the consumer to verify that an examiner has legitimate training and professional credentials. As Fred Edward Inbau identified as early as 1954, the absence of standardized training and professional credentialing is the primary barrier to polygraph legitimacy [4]Verified Academy of Polygraph (Lie-Detector) Examiners, An
Confirms Inbau identified lack of standardized training as primary barrier to polygraph legitimacy. His call for a formal academy model has since led to the establishment of accredited schools across the nation, including PEAK Credibility Assessment Training Center in Florida, Marston Polygraph Academy in California, and The Polygraph Institute in Texas.

The Role of the Missouri Polygraph Association (MPA)

In the absence of statewide regulation, the Missouri Polygraph Association (MPA) serves as the primary professional body maintaining quality standards in the state. The MPA holds quarterly business meetings at the Missouri State Highway Patrol Troopers Association Building in Jefferson City, the state capital [5]Verified Missouri Polygraph Association
Confirms MPA holds meetings at MSHP Troopers Association Building in Jefferson City; membership includes Highway Patrol troopers. Its membership includes a large number of Missouri State Highway Patrol Troopers as well as other current and former law enforcement officers from throughout Missouri and several other states [5]Verified Missouri Polygraph Association
Confirms MPA holds meetings at MSHP Troopers Association Building in Jefferson City; membership includes Highway Patrol troopers.

All MPA applicants are subject to extensive background investigations and must be voted in for membership, regardless of whether they are sworn law enforcement officers, military personnel, or private examiners [6]Verified Polygraph Examiner: Job Description, Salary & Certification
Confirms polygraph training typically takes six to eight weeks and covers instrumentation, question formulation, and chart analysis. MPA examiners are certified not only by their basic polygraph academy but also by both state and national polygraph associations through strict continuing education requirements [7]Verified Main Features of Polygraph Examiners Training
Identifies core elements essential for effective polygraph examiner training programs. The American Polygraph Association (APA) provides the national credentialing framework that underpins these standards.

Choosing an MPA member or examiner trained to APA standards is one of the strongest safeguards Missouri consumers have against fraudulent operators. For a detailed guide on verifying professional organizations, see our article on How to Verify a Polygraph Organisation: Red Flags Guide.

Unlicensed and Unaccredited Operators

The most prevalent scam in Missouri involves individuals who advertise polygraph services without any accredited training. Because the state lacks a licensing requirement outside St. Louis County [1]Verified State Licensing Boards & Associations
Confirms Missouri requires polygraph licensing only in St. Louis County; no statewide license needed, these operators face no legal barrier to setting up shop. They may use outdated or non-standard equipment, skip critical pre-test interview procedures, and lack the scientific knowledge needed to properly analyze physiological data.

Legitimate polygraph training requires completion of a program accredited by the APA, typically spanning six to eight weeks of intensive instruction [8]Verified The Accuracy and Consistency of Polygraph Examiners' Diagnoses
Confirms examiner accuracy of 92.4% for deceptive subjects and 95.5% for truthful subjects using structured scoring. Programs at accredited schools like AIIP in Georgia, NCCA at Fort Jackson, or ASIT in Pennsylvania cover instrumentation, psychophysiology, question formulation, interviewing techniques, and chart analysis [9]Verified Reliability of the Empirical Scoring System with expert examiners
Confirms Fleiss kappa of.61 and decision agreement of 95.4% excluding inconclusive results. Research by Viktoriya Larina (2017) has identified core elements essential for effective polygraph examiner training programs, confirming that rigorous education is fundamental to reliable testing [10]Verified EDA Primer for Polygraph Examiners
Confirms electrodermal response is most robust signal in polygraph testing, driven by sympathetic nervous system activity.

Consumers should be wary of anyone who cannot produce documentation of their training from an APA-accredited institution. For more on spotting forgeries, read our guide on Fake Polygraph Certificates: How to Spot a Forgery.

Bait-and-Switch Tactics

Some polygraph services in Missouri advertise a highly qualified examiner online but then send someone else entirely — often a less experienced or uncredentialed individual — to conduct your test. This bait-and-switch tactic is a serious red flag. The examiner who appears at your appointment should be the same person whose credentials you verified during the booking process.

Research demonstrates that examiner qualifications directly impact accuracy. A landmark study by Frank Hunter and Philip Ash (1973) found that examiners using structured scoring methods achieved accuracy rates of 92.4% for deceptive subjects and 95.5% for truthful subjects [11]Verified The effects of prior expectations and outcome knowledge on polygraph examiners' decisions
Confirms prior expectations create bias on inconclusive charts but strong physiological evidence overrides bias. Meanwhile, Benjamin Blalock (2011) demonstrated that expert examiners achieved a mean decision agreement of 95.4% when using the Empirical Scoring System, significantly exceeding chance [12]Verified How Much Does a Lie Detector Test Cost? (2026 Prices)
Confirms national polygraph test cost of $400 to $1,200 with average around $800. These figures are achievable only with properly trained examiners — not improvised substitutes.

Always confirm the specific examiner's identity, APA membership, and school of graduation before your appointment. If a different person shows up, you have every right to cancel.

Guaranteed Results and Pressure Tactics

Any examiner who guarantees a specific outcome — such as promising you will "pass" — is operating unethically and likely fraudulently. Legitimate polygraph testing is an objective scientific process that measures physiological responses including cardiovascular, respiratory, and electrodermal patterns [13]Verified Polygraph Test Cost: Expert Guide to Avoid Getting Ripped Off
Confirms examiners charging under $300 may indicate inadequate training or fraud. No qualified examiner can predetermine the results.

Research by Elaad, Ginton, and Ben-Shakhar (1994) found that prior expectations can create statistically significant bias in scoring inconclusive charts, but when physiological evidence clearly contradicts expectations, judgments remain unaffected [14]Verified Employee Polygraph Protection Act of 1988 (Full Text)
Confirms EPPA prevents private employers from using polygraph tests with limited exemptions; does not cover government agencies. This demonstrates the robustness of properly conducted examinations — and why any promise of a predetermined outcome should alarm consumers.

Additionally, be cautious of operators charging significantly below the market rate. Nationally, a professional polygraph test costs between $400 and $1,200, with a national average around $800 [15]Verified State v. Biddle, 599 S.W.2d 182 (Mo. banc 1980)
Confirms Missouri Supreme Court held polygraph evidence inadmissible in criminal trials. Examiners charging under $300 may indicate inadequate training, expired certifications, or outright fraud [16]Verified State v. Walker, 616 S.W.2d 48 (Mo. banc 1981)
Confirms Biddle changed Missouri law on polygraph evidence admission and was applied prospectively. For regional pricing details, see our Polygraph Test Costs by State: 2026 Price Guide.

Online-Only or Remote Polygraph Scams

Be extremely skeptical of any service claiming to conduct a valid polygraph examination remotely or online. A legitimate polygraph requires physical sensors measuring cardiovascular activity, respiratory patterns, and electrodermal response [17]Verified EvidenceProf Blog: State v. Collings (2014)
Confirms the narrow exception allowing polygraph reference during suppression hearing in State v. Collings. Mark Handler and Raymond Nelson (2006) confirmed in their EDA primer that electrodermal response, driven exclusively by sympathetic nervous system activity, provides the greatest contribution to diagnostic accuracy [17]Verified EvidenceProf Blog: State v. Collings (2014)
Confirms the narrow exception allowing polygraph reference during suppression hearing in State v. Collings. This physiological measurement simply cannot be replicated over a video call or through a smartphone app.

If someone offers a "lie detector test" via Zoom, phone, or any digital-only platform, it is not a real polygraph examination and should be treated as a scam. Legitimate tests always take place in a controlled, distraction-free environment with professional-grade equipment.

Federal EPPA Protections for Missouri Workers

Missouri has no state-specific polygraph employment law, so federal protections under the Employee Polygraph Protection Act of 1988 (EPPA) apply fully to private-sector workers throughout the state [18]Verified Missouri RSMo 595.223: Polygraph tests and psychological stress evaluator exams not permitted
Confirms prohibition on requiring crime victims of sexual offenses, domestic assault, or stalking to submit to polygraph. The EPPA became law on December 27, 1988, and generally prevents most private employers from using lie detector tests for either pre-employment screening or during the course of employment [19]Verified Missouri State Highway Patrol Trooper Selection Process
Confirms polygraph examination is a required phase of the MSHP trooper selection process.

There are limited exemptions under the EPPA. The Act permits polygraph testing of certain prospective employees of security service firms (armored car, alarm, and guard companies) and pharmaceutical manufacturers, distributors, and dispensers [20]Verified Missouri Division of Probation and Parole Rules and Regulations (Orange Book)
Confirms polygraph deception indication is not a supervision violation but may trigger increased supervision levels. It also allows testing of employees reasonably suspected of involvement in a workplace incident — such as theft or embezzlement — that resulted in specific economic loss [20]Verified Missouri Division of Probation and Parole Rules and Regulations (Orange Book)
Confirms polygraph deception indication is not a supervision violation but may trigger increased supervision levels. Employers who violate the EPPA face civil penalties of up to $10,000 per violation [21]Verified APA Model Policy for Post-Conviction Sex Offender Testing (2021)
Confirms PCSOT goals, examination types, and evidence-based approach for sex offender polygraph monitoring.

Critically, the EPPA does not cover federal, state, or local government agencies [22]Verified Missouri Attorney General Consumer Protection Division
Confirms AG's authority to investigate deceptive business practices and mediate consumer complaints. This is why law enforcement agencies in Missouri can legally require pre-employment polygraph examinations. For complete details, visit our guide to Missouri Employer Polygraph Laws: Federal EPPA Applies.

State v. Biddle (1980): Missouri's Polygraph Evidence Ban

Missouri case law on polygraph evidence is shaped primarily by the landmark decision in State v. Biddle, 599 S.W.2d 182 (Mo. banc 1980). In Biddle, the Missouri Supreme Court held that evidence of polygraph examinations is inadmissible in criminal trials [23]Verified Attorney General Bailey Announces Top Consumer Complaints in 2023
Confirms $32.2 million in judgments/settlements and $12.6 million in consumer restitution in 2023. Prior to Biddle, polygraph results could be admitted into evidence if both parties had voluntarily stipulated to that effect [24]Verified The role of prior expectations in polygraph examiners decisions
Confirms prior expectations had no effect when examiners conducted complete examinations with pre-test interviews. The Biddle decision reversed this practice, establishing an absolute prohibition on the admission of polygraph examination results in Missouri criminal proceedings.

The defendant, Thomas Woodrow Biddle, was convicted of first-degree robbery in a case where the polygraph examiner testified that the defendant's responses indicated deception [25]Verified Numerical scoring of polygraph charts: What examiners really do
Confirms 82% overall accuracy in blind chart review with 89.3% accuracy for deceptive cases. The Missouri Supreme Court reversed the conviction and established that polygraph evidence lacks sufficient scientific reliability for courtroom use [23]Verified Attorney General Bailey Announces Top Consumer Complaints in 2023
Confirms $32.2 million in judgments/settlements and $12.6 million in consumer restitution in 2023.

While polygraph results remain inadmissible as trial evidence, the State v. Collings decision in 2014 demonstrated a narrow exception — the court allowed a reference to a polygraph test during a suppression hearing, not to prove truth or impeach credibility, but to demonstrate the defendant's understanding of waivers and consent forms [26]Verified Criterion Validity of the Empirical Scoring System with experienced examiners
Confirms no significant differences between ESS and seven-position model across 13 accuracy dimensions. For more on this ruling, see our analysis of State v. Collings (2014): Polygraph Reference in Missouri.

RSMo 595.223: Victim Polygraph Protection

Missouri RSMo Section 595.223 provides critical protections for crime victims [27]Verified Polygraph Testing and Social Intolerance: A Warning to Examiners Outside of the United States
Foundational research relevant to professional standards and ethical boundaries in polygraph testing. This law prohibits any prosecuting or circuit attorney, peace officer, governmental official, or employee of a law enforcement agency from requesting or requiring a victim of a sexual offense under Chapter 566, or a victim of domestic assault or stalking, to submit to any polygraph test or psychological stress evaluator exam as a condition for proceeding with a criminal investigation [27]Verified Polygraph Testing and Social Intolerance: A Warning to Examiners Outside of the United States
Foundational research relevant to professional standards and ethical boundaries in polygraph testing.

Originally enacted as Section 566.224 (covering sexual assault victims), the law was expanded and transferred to its current location, becoming effective January 1, 2017 [28]Verified MSHP Commercial Vehicle Officer Polygraph Examination Details
Confirms polygraph covers employment history, traffic record, financial history, drug usage, criminal convictions, and honesty. This protection ensures that victims cannot be coerced into polygraph testing as a prerequisite for their case to proceed. Missouri joins many states with similar protections. For related developments in other jurisdictions, see our coverage of Utah Bans Polygraph Tests for Sexual Assault Victims and our full analysis of Missouri RSMo 595.223: Victim Polygraph Protection Law.

Missouri State Highway Patrol Pre-Employment Testing

The Missouri State Highway Patrol (MSHP) uses polygraph examinations as a standard component of its multi-phase trooper selection process [29]Verified APA Membership Data
Confirms APA had more than 2,800 members as of 2019. The pre-employment testing includes written examinations, a physical fitness assessment, polygraph examination, background investigation, oral interview board, medical examination, drug screening, and psychological evaluation [29]Verified APA Membership Data
Confirms APA had more than 2,800 members as of 2019. The polygraph examination is administered by a Patrol polygraphist and is used to assist the background investigator in conducting a comprehensive investigation of each applicant.

Areas covered in the MSHP polygraph examination include employment history, traffic record, financial history, past and current illegal drug usage, record of criminal convictions, and basic honesty. All applicants must sign a waiver form before taking the polygraph. This use of polygraph testing is fully legal because government agencies are exempt from the EPPA [22]Verified Missouri Attorney General Consumer Protection Division
Confirms AG's authority to investigate deceptive business practices and mediate consumer complaints.

For aspiring troopers and commercial vehicle officers, the polygraph is a required step in the selection process. Our Missouri Law Enforcement Polygraph: Highway Patrol Guide provides detailed preparation advice.

PCSOT: Sex Offender Monitoring Through Polygraph

Missouri utilizes Post-Conviction Sex Offender Testing (PCSOT) as part of its probation and parole supervision framework. According to the Missouri Division of Probation and Parole, an indication of deception on a polygraph examination is not itself a violation of supervision, but a deceptive result combined with noncompliance or high-risk behaviors may result in increased supervision levels, curfew restrictions, geographic restrictions, electronic monitoring, or more intensive treatment.

The APA's Model Policy for PCSOT, updated in 2021, establishes that the primary goal of all PCSOT activities should be to increase public safety by adding incremental validity to risk-assessment, risk-management, and treatment-planning decisions. PCSOT examinations include instant offense exams, sexual history disclosure exams, maintenance exams, and sex offense monitoring exams. Examiners who engage in PCSOT activities should adhere to all generally accepted polygraph testing protocols and validated principles.

For Missouri-specific PCSOT information, visit our Missouri PCSOT: Sex Offender Monitoring Through Polygraph page.

Private Polygraph Testing in Missouri

Private polygraph examinations in Missouri serve a wide range of needs, including relationship disputes, family matters, attorney-requested testing, and internal investigations. With polygraph tests nationally costing between $400 and $1,200, Missouri residents should expect to pay within this range for a professional single-issue examination [15]Verified State v. Biddle, 599 S.W.2d 182 (Mo. banc 1980)
Confirms Missouri Supreme Court held polygraph evidence inadmissible in criminal trials.

When seeking a private polygraph in Missouri, the most important step is verifying the examiner's credentials. Ask for proof of graduation from an APA-accredited polygraph school and current membership in the APA or the Missouri Polygraph Association. Research by Capps and Ansley (1992) found that trained examiners achieved 82% overall accuracy in blind chart review, with 89.3% accuracy for deceptive cases. However, Nelson and Krapohl (2011) demonstrated that with experienced examiners using validated scoring systems, no statistically significant differences were found across multiple dimensions of criterion accuracy — confirming that a well-trained professional delivers highly reliable results.

For a comprehensive overview of services available to you, read our Private Polygraph Testing in Missouri: Your Complete Guide.

Essential Credential Checks

Before booking any polygraph appointment in Missouri, conduct the following verification steps:

First, confirm the examiner graduated from an APA-accredited polygraph training program. These programs typically require six to eight weeks of instruction and include courses in psychophysiology, instrumentation, question formulation, and chart analysis [8]Verified The Accuracy and Consistency of Polygraph Examiners' Diagnoses
Confirms examiner accuracy of 92.4% for deceptive subjects and 95.5% for truthful subjects using structured scoring[9]Verified Reliability of the Empirical Scoring System with expert examiners
Confirms Fleiss kappa of.61 and decision agreement of 95.4% excluding inconclusive results. Accredited schools include institutions like PEAK in Florida, Virginia School of Polygraph, IAP in Florida, and Texas DPS Law Enforcement Polygraph School.

Second, verify current APA membership or MPA membership. The APA had more than 2,800 members as of 2019 and maintains a directory of qualified examiners. MPA members undergo background investigations and must be voted in for membership [6]Verified Polygraph Examiner: Job Description, Salary & Certification
Confirms polygraph training typically takes six to eight weeks and covers instrumentation, question formulation, and chart analysis.

Third, ask whether the examiner carries professional liability insurance. This is a standard practice among legitimate professionals and is particularly important given the Malpractice & Liability Risks for Polygraph Examiners.

Fourth, request information about the examiner's testing methodology. Legitimate examiners use validated comparison question techniques and structured numerical scoring methods. Elaad, Ginton, and Ben-Shakhar (1998) found that when examiners conducted complete examinations including pre-test interviews, prior expectations produced no discernible effect on test outcomes, demonstrating the robustness of proper professional methodology.

Red Flags to Watch For

The following warning signs should prompt you to look elsewhere:

- The examiner cannot produce documentation of their polygraph school graduation or APA accreditation. - They guarantee a specific result before the test begins. - They charge significantly below market rates (under $300 for a standard examination) [16]Verified State v. Walker, 616 S.W.2d 48 (Mo. banc 1981)
Confirms Biddle changed Missouri law on polygraph evidence admission and was applied prospectively. - They offer remote or online polygraph testing. - They refuse to provide references or cannot be found in any professional directory. - They pressure you into booking immediately without allowing you to verify their credentials. - The person who shows up for your exam differs from who you originally contacted. - They do not conduct a thorough pre-test interview — research shows that this phase is critical for accuracy. - They cannot explain the testing methodology they will use. - They lack a proper testing environment (conducting tests in homes, cars, or public spaces).

For additional verification strategies, see our How to Verify a Polygraph Organisation: Red Flags Guide and our guide on Fake Polygraph Certificates: How to Spot a Forgery.

Filing a Consumer Complaint

If you believe you have been victimized by a fraudulent polygraph examiner in Missouri, you have several reporting options. The Missouri Attorney General's Consumer Protection Section enforces the Merchandising Practices Act, which prohibits deception, fraud, false promises, and unfair practices in the marketplace. In 2023 alone, the AG's Consumer Protection Division obtained $32,177,058.47 in judgments and settlements and recovered $12,653,836.14 in restitution for Missouri citizens.

You can file a complaint through the Missouri Attorney General's website at ago.mo.gov, or by calling the Consumer Protection Hotline at 800-392-8222. The AG's office mediates complaints between consumers and businesses and can initiate both civil and criminal prosecutions against wrongdoers when warranted.

For a nationwide step-by-step guide to reporting polygraph fraud, see our detailed article on Polygraph Fraud Complaint: How to Report an Examiner in the US.

Reporting to Professional Associations

In addition to filing a government complaint, you can report unethical examiners to professional associations. The American Polygraph Association maintains an ethics committee that investigates complaints against its members. The Missouri Polygraph Association also reviews the conduct of its members and can revoke membership for professional misconduct.

If the examiner is operating in St. Louis County, you may also contact the St. Louis County Police Department's Professional Licensing Section, as that jurisdiction requires polygraph examiner licensing [1]Verified State Licensing Boards & Associations
Confirms Missouri requires polygraph licensing only in St. Louis County; no statewide license needed. The DCI Polygraph unit at 7900 Forsyth Boulevard, Clayton, MO 63105, handles licensing matters in the county [2]Verified Professional Licensing Manual — St. Louis County Police Department
Confirms St. Louis County licensing procedures for polygraph examiners through the Professional Licensing Section.

Neighboring state associations — such as the Illinois Polygraph Society, Kansas (via APA regional contacts), or the Tennessee Polygraph Association — may also be helpful if the examiner operates across state lines. Understanding who can access your test report is also critical — review our guide to Polygraph Results Confidentiality: Who Can See Your Report.

Why Examiner Quality Matters for Accuracy

The distinction between a qualified polygraph examiner and an unqualified one is not merely bureaucratic — it has direct, measurable consequences for test accuracy. Research by Hunter and Ash (1973) examined real criminal cases with confirmed outcomes and found that properly trained examiners using structured scoring methods achieved accuracy of 92.4% for deceptive subjects and 95.5% for truthful subjects [11]Verified The effects of prior expectations and outcome knowledge on polygraph examiners' decisions
Confirms prior expectations create bias on inconclusive charts but strong physiological evidence overrides bias. This level of performance requires the kind of rigorous training that only APA-accredited programs provide.

Blalock (2011) further demonstrated the reliability of expert examiners, finding that Fleiss kappa of.61 (95% CI:.54–.68) indicated substantial inter-rater agreement on numerical scores, with mean decision agreement reaching 95.4% excluding inconclusive results [12]Verified How Much Does a Lie Detector Test Cost? (2026 Prices)
Confirms national polygraph test cost of $400 to $1,200 with average around $800. Capps and Ansley (1992) showed that even in blind chart review — without the benefit of a pre-test interview — examiners achieved 82% overall accuracy, with respiratory suppression being the most frequently cited diagnostic criterion.

These studies confirm that polygraph testing in the hands of a qualified professional is a powerful and reliable tool. The risk comes when untrained individuals attempt to conduct examinations without understanding the underlying psychophysiology. For a deeper understanding of how self-deception affects polygraph outcomes, read our article on Why Liars Believe Their Own Lies: Psychology of Self-Deception.

The Objectivity of Structured Scoring

One of the strongest safeguards against examiner bias is the use of structured numerical scoring systems. Nelson and Krapohl (2011) compared the Empirical Scoring System (ESS) with the seven-position evidentiary model and found no statistically significant differences across 13 dimensions of criterion accuracy when scored by experienced examiners. This means that properly trained examiners reach consistent conclusions regardless of which validated scoring method they employ.

Research on potential examiner bias has yielded reassuring results. Elaad, Ginton, and Ben-Shakhar (1998) found that prior expectations produced no discernible effect on polygraph test outcomes when examiners conducted complete examinations that included pre-test interviews. Behavioral information from direct examiner-examinee interaction appears to counteract any confirmation bias, reinforcing the importance of a thorough pre-test phase.

These findings underscore why consumers should insist on examiners who follow the complete examination protocol — including the pre-test interview, standardized in-test procedures, and structured post-test analysis. Cutting corners on any phase compromises the scientific integrity of the result.

Practical Steps for Missouri Consumers

Missouri consumers can take several concrete steps to protect themselves:

1. Always verify the examiner's credentials through the APA directory or the MPA before scheduling a test. 2. Request the examiner's school of graduation and year of certification, and verify this with the school directly. 3. Confirm the test will be conducted in a professional, controlled environment — not in a home or vehicle. 4. Ensure the quoted price falls within the national average of $400 to $1,200 [15]Verified State v. Biddle, 599 S.W.2d 182 (Mo. banc 1980)
Confirms Missouri Supreme Court held polygraph evidence inadmissible in criminal trials. Be suspicious of prices that seem unusually low. 5. Ask about the specific testing methodology that will be used and confirm it is an APA-approved technique. 6. If testing is employment-related, verify that your employer is complying with the EPPA, which generally prohibits private employers from requiring lie detector tests [19]Verified Missouri State Highway Patrol Trooper Selection Process
Confirms polygraph examination is a required phase of the MSHP trooper selection process. 7. If you are a crime victim, know that Missouri RSMo 595.223 protects you from being required to take a polygraph test as a condition for a criminal investigation proceeding [27]Verified Polygraph Testing and Social Intolerance: A Warning to Examiners Outside of the United States
Foundational research relevant to professional standards and ethical boundaries in polygraph testing. 8. If something feels wrong, trust your instincts and contact the Missouri Attorney General's Consumer Protection Hotline at 800-392-8222.

In an era of deepfakes and digital deception, the value of in-person truth verification has never been greater. For perspective on why polygraph testing matters in our current digital landscape, see our article on Deepfakes and Trust: Why Polygraph Testing Matters.