Maryland Polygraph Court Admissibility: Legal Guide

Historical Foundation: From Lusby to Rawlings

Maryland's exclusionary stance on polygraph evidence traces back to the 1958 decision in Lusby v. State, 217 Md. 191, where the Court of Appeals observed that "the result of a lie detector test is almost universally excluded as evidence" [1]Verified Lusby v. State, 217 Md. 191, 141 A.2d 893 (1958)
Confirms the Maryland Court of Appeals observed polygraph results are 'almost universally excluded as evidence' in 1958. While the Lusby court did not directly rule on polygraph admissibility — the mention of a lie detector test by a witness was addressed through a jury instruction to disregard — the court's language signalled Maryland's alignment with the overwhelming majority of jurisdictions rejecting such evidence [1]Verified Lusby v. State, 217 Md. 191, 141 A.2d 893 (1958)
Confirms the Maryland Court of Appeals observed polygraph results are 'almost universally excluded as evidence' in 1958.

The first direct Maryland holding came in Rawlings v. State, 7 Md. App. 611 (1969), a case of first impression in which the defendant sought to introduce polygraph results from a test administered at his own request [2]Verified Rawlings v. State, 7 Md. App. 611, 256 A.2d 704 (1969)
Confirms Maryland's first direct holding that polygraph evidence is inadmissible, establishing the foundational precedent. The Court of Special Appeals followed the general rule that polygraph evidence is inadmissible, citing the landmark New Hampshire decision in State v. LaForest (1965), which held that polygraph test results "have not yet attained sufficient scientific acceptance as an accurate and reliable means of ascertaining truth or deception" [2]Verified Rawlings v. State, 7 Md. App. 611, 256 A.2d 704 (1969)
Confirms Maryland's first direct holding that polygraph evidence is inadmissible, establishing the foundational precedent. The Rawlings court found this rationale represented "the sounder approach to the issue" despite assertions that advances in polygraph science might warrant a different result [2]Verified Rawlings v. State, 7 Md. App. 611, 256 A.2d 704 (1969)
Confirms Maryland's first direct holding that polygraph evidence is inadmissible, establishing the foundational precedent.

Johnson v. State: Polygraph Use in Interrogation Context

The 1976 decision in Johnson v. State, 31 Md. App. 303, carved out an important distinction within Maryland's polygraph jurisprudence [3]Verified Johnson v. State, 31 Md. App. 303 (1976)
Confirms that while polygraph results are inadmissible, the fact of polygraph use during interrogation may be disclosed to juries evaluating confession voluntariness. The court held that while polygraph results themselves remain inadmissible, the fact that a polygraph was used during an interrogation may be disclosed to the jury when evaluating the voluntariness of a confession [3]Verified Johnson v. State, 31 Md. App. 303 (1976)
Confirms that while polygraph results are inadmissible, the fact of polygraph use during interrogation may be disclosed to juries evaluating confession voluntariness. In Johnson, police used a polygraph machine twice during questioning, and the interrogating officer repeatedly told the defendant he had failed the test. The court reasoned that the jury should have the opportunity to decide whether the psychological impact of the polygraph had a coercive effect rendering the resulting confession involuntary [3]Verified Johnson v. State, 31 Md. App. 303 (1976)
Confirms that while polygraph results are inadmissible, the fact of polygraph use during interrogation may be disclosed to juries evaluating confession voluntariness.

This distinction remains significant for defense attorneys in Maryland, as it opens a limited pathway for polygraph-related information to reach the jury — not for its truth-finding value, but as context for evaluating law enforcement interrogation methods. For more on how polygraph results affect legal proceedings, see our guide to criminal issues for lie detector testing.

Akonom v. State: Stipulations Cannot Override Inadmissibility

In the landmark 1978 decision Akonom v. State, 40 Md. App. 676, the Court of Special Appeals addressed whether a stipulation between the prosecution and defense could render polygraph evidence admissible [4]Verified Akonom v. State, 40 Md. App. 676, 394 A.2d 1213 (1978)
Confirms that even a stipulation between parties cannot make polygraph evidence admissible in Maryland; adherence to exclusionary policy from Rawlings. The defendant Gregg had signed a pre-examination agreement stating that either party could introduce conclusive test results at trial [4]Verified Akonom v. State, 40 Md. App. 676, 394 A.2d 1213 (1978)
Confirms that even a stipulation between parties cannot make polygraph evidence admissible in Maryland; adherence to exclusionary policy from Rawlings. The court firmly rejected the stipulation approach, holding that a party agreement "neither enhances in any significant way the inherent reliability of evidence produced by a so-called scientific process or art" [4]Verified Akonom v. State, 40 Md. App. 676, 394 A.2d 1213 (1978)
Confirms that even a stipulation between parties cannot make polygraph evidence admissible in Maryland; adherence to exclusionary policy from Rawlings.

The Akonom court emphasized that polygraph evidence fails to meet the Frye-Reed standard of general scientific acceptance and that its admission would be highly prejudicial because of its "apparent conclusiveness" [4]Verified Akonom v. State, 40 Md. App. 676, 394 A.2d 1213 (1978)
Confirms that even a stipulation between parties cannot make polygraph evidence admissible in Maryland; adherence to exclusionary policy from Rawlings. This ruling placed Maryland among the minority of states that refuse to admit polygraph evidence even by mutual consent — a position that remains unchanged. The court reversed both defendants' convictions, finding the introduction of the polygraph evidence "necessarily so prejudicial" as to warrant reversal [4]Verified Akonom v. State, 40 Md. App. 676, 394 A.2d 1213 (1978)
Confirms that even a stipulation between parties cannot make polygraph evidence admissible in Maryland; adherence to exclusionary policy from Rawlings. For a comparison of how other states handle stipulated polygraph evidence, see the Corbett v. State Nevada stipulation standard.

State v. Hawkins: The Red Flag Doctrine

The Maryland Court of Appeals cemented the state's per se exclusion rule in State v. Hawkins, 604 A.2d 489 (Md. 1992), establishing what has become known as the "red flag" doctrine [5]Verified State v. Hawkins, 604 A.2d 489, 326 Md. 270 (1992)
Confirms Maryland Court of Appeals established per se rule of polygraph inadmissibility and the 'red flag' doctrine for any polygraph references in criminal prosecutions. The court declared that the word "polygraph," when it crops up in a criminal prosecution, "raises a red flag" [5]Verified State v. Hawkins, 604 A.2d 489, 326 Md. 270 (1992)
Confirms Maryland Court of Appeals established per se rule of polygraph inadmissibility and the 'red flag' doctrine for any polygraph references in criminal prosecutions. In this first-degree felony murder case, even incidental references to polygraph testing by two police officers during testimony were considered potentially prejudicial to the defendant [5]Verified State v. Hawkins, 604 A.2d 489, 326 Md. 270 (1992)
Confirms Maryland Court of Appeals established per se rule of polygraph inadmissibility and the 'red flag' doctrine for any polygraph references in criminal prosecutions.

The Hawkins decision reinforced decades of Maryland precedent by making clear that not only are polygraph results inadmissible, but even indirect references to polygraph examinations can taint criminal proceedings. This broad prohibition extends to a witness's willingness or refusal to take a polygraph test, as established in earlier decisions citing Kosmas v. State [5]Verified State v. Hawkins, 604 A.2d 489, 326 Md. 270 (1992)
Confirms Maryland Court of Appeals established per se rule of polygraph inadmissibility and the 'red flag' doctrine for any polygraph references in criminal prosecutions. The Maryland State Police Polygraph Unit operates under this framework, emphasizing that polygraph examinations are voluntary and their results serve investigative rather than evidentiary purposes [6]Verified Maryland State Police Polygraph Unit — Commonly Asked Questions
Confirms the three-phase polygraph examination process, voluntary nature of testing, and quality control procedures used by Maryland State Police.

Rochkind v. Stevenson (2020): A Landmark Shift

On August 28, 2020, the Maryland Court of Appeals issued a 4-3 decision in Rochkind v. Stevenson, 471 Md. 1, adopting the Daubert standard as the governing framework for evaluating expert testimony and retiring the long-standing Frye-Reed standard [7]Verified Rochkind v. Stevenson, 471 Md. 1, 236 A.3d 630 (2020) — Court of Appeals Opinion
Confirms Maryland Court of Appeals retired Frye-Reed standard and adopted Daubert framework for expert testimony on August 28, 2020. The court recognized that Maryland had experienced a "jurisprudential drift" over four decades, with the Frye-Reed standard slowly morphing into a "Frye-Reed Plus" standard that implicitly incorporated Daubert principles [7]Verified Rochkind v. Stevenson, 471 Md. 1, 236 A.3d 630 (2020) — Court of Appeals Opinion
Confirms Maryland Court of Appeals retired Frye-Reed standard and adopted Daubert framework for expert testimony on August 28, 2020.

The Rochkind decision brought Maryland in line with the supermajority of states and the federal courts that follow the Daubert framework [8]Verified Maryland Adopts Daubert Standard for Expert Testimony — Expert Institute
Confirms the 4-3 decision in Rochkind replaced Frye-Reed with Daubert and Maryland joined the supermajority of states following Daubert. Under Daubert, trial judges serve as gatekeepers who evaluate expert testimony based on multiple factors including whether the theory or technique has been tested, whether it has been subjected to peer review and publication, its known or potential error rate, and whether it is generally accepted in the relevant scientific community [7]Verified Rochkind v. Stevenson, 471 Md. 1, 236 A.3d 630 (2020) — Court of Appeals Opinion
Confirms Maryland Court of Appeals retired Frye-Reed standard and adopted Daubert framework for expert testimony on August 28, 2020. This more flexible standard replaces the rigid Frye-Reed requirement that expert opinions must be based on methods "generally accepted as reliable" within the scientific community [8]Verified Maryland Adopts Daubert Standard for Expert Testimony — Expert Institute
Confirms the 4-3 decision in Rochkind replaced Frye-Reed with Daubert and Maryland joined the supermajority of states following Daubert.

Implications for Polygraph Admissibility

The shift to Daubert creates a potentially significant opening for future polygraph admissibility challenges in Maryland [9]Verified Maryland Adopts Daubert Standard — Faegre Drinker on Products
Confirms Maryland officially joined the supermajority of states following Daubert with the Rochkind decision on August 28, 2020. Under the old Frye-Reed standard, the Akonom court's 1978 finding that polygraph evidence lacked "general acceptance" among psychologists and physiologists effectively closed the door on admissibility arguments. The Daubert framework, by contrast, allows courts to evaluate scientific evidence on a case-by-case basis using multiple reliability factors rather than relying solely on general acceptance [7]Verified Rochkind v. Stevenson, 471 Md. 1, 236 A.3d 630 (2020) — Court of Appeals Opinion
Confirms Maryland Court of Appeals retired Frye-Reed standard and adopted Daubert framework for expert testimony on August 28, 2020.

The Fifth Circuit's experience following Daubert is instructive. In United States v. Posado (1995), the court overturned its per se rule against polygraph evidence, reasoning that the rule "was based on antiquated concepts about the technical ability of the polygraph and legal precepts that have been expressly overruled" [10]Verified Polygraph Case Law — Veridicus Inc.
Confirms the Fifth Circuit in United States v. Posado (1995) overturned its per se rule against polygraph evidence after Daubert. Defense attorneys in Maryland who wish to challenge the state's per se polygraph exclusion now have a stronger legal framework for doing so, particularly when they can demonstrate that a specific polygraph technique has been validated through peer-reviewed research, has a known error rate, and meets the other Daubert criteria [9]Verified Maryland Adopts Daubert Standard — Faegre Drinker on Products
Confirms Maryland officially joined the supermajority of states following Daubert with the Rochkind decision on August 28, 2020. Research on the evolving science of polygraph testing can be found in our Polygraph Research Database.

Post-Rochkind Developments

Since Rochkind, Maryland courts have actively grappled with the practical application of Daubert standards [11]Verified Maryland Courts Continue to Provide Guidance on Newly-Adopted Daubert Standard — Franklin & Prokopik
Confirms increasing post-Rochkind challenges to expert testimony and appellate reversals including State v. Matthews (2022) and Oglesby (2023). The Supreme Court of Maryland has reversed several Appellate Court rulings on expert testimony admissibility, including State v. Matthews (2022) and Oglesby v. Baltimore School Associates (2023), indicating that the state's highest court is taking the Daubert gatekeeping function seriously [11]Verified Maryland Courts Continue to Provide Guidance on Newly-Adopted Daubert Standard — Franklin & Prokopik
Confirms increasing post-Rochkind challenges to expert testimony and appellate reversals including State v. Matthews (2022) and Oglesby (2023). For practitioners and defense attorneys, this evolving landscape means that challenges to the per se exclusion of polygraph evidence are now at least procedurally viable, even if success remains uncertain.

The ongoing development of how software changed the lie detector test adds additional weight to future Daubert challenges, as computerized scoring algorithms provide more standardized and measurable results than earlier manual methods.

Maryland Labor Code §3-702: Employer Prohibitions

Under Maryland Labor and Employment Code §3-702, employers are broadly prohibited from requiring polygraph examinations as a condition of employment, prospective employment, or continued employment [12]Verified Maryland Labor and Employment Code §3-702 — Lie Detector Tests (2024)
Confirms employer prohibition on requiring polygraph tests, misdemeanor penalties, and detailed exemptions for law enforcement and corrections. The statute mandates that every employment application must include, in bold-faced upper case type, a notice informing applicants that employers may not require polygraph examinations under Maryland law [12]Verified Maryland Labor and Employment Code §3-702 — Lie Detector Tests (2024)
Confirms employer prohibition on requiring polygraph tests, misdemeanor penalties, and detailed exemptions for law enforcement and corrections. Employers who violate this provision are guilty of a misdemeanor and subject to a fine not exceeding $100 [12]Verified Maryland Labor and Employment Code §3-702 — Lie Detector Tests (2024)
Confirms employer prohibition on requiring polygraph tests, misdemeanor penalties, and detailed exemptions for law enforcement and corrections.

If an employer violates the statute, applicants and employees may submit a written complaint to the Commissioner, who may attempt to resolve the matter through mediation or refer the case to the Attorney General for legal action [12]Verified Maryland Labor and Employment Code §3-702 — Lie Detector Tests (2024)
Confirms employer prohibition on requiring polygraph tests, misdemeanor penalties, and detailed exemptions for law enforcement and corrections. The Attorney General may bring an action for injunctive relief, damages, or other relief in the county where the violation occurred [12]Verified Maryland Labor and Employment Code §3-702 — Lie Detector Tests (2024)
Confirms employer prohibition on requiring polygraph tests, misdemeanor penalties, and detailed exemptions for law enforcement and corrections. For a comparison of how other states handle employer polygraph rights, see our guides on Nevada NRS 613.440, New Jersey statute 2C:40A-1, and Louisiana employer polygraph rights.

Law Enforcement and Corrections Exemptions

Maryland's employer polygraph prohibition includes extensive exemptions for public safety positions [12]Verified Maryland Labor and Employment Code §3-702 — Lie Detector Tests (2024)
Confirms employer prohibition on requiring polygraph tests, misdemeanor penalties, and detailed exemptions for law enforcement and corrections. The law does not apply to individuals who apply for employment or are employed as law enforcement officers, employees of law enforcement agencies of the state, county, or municipal corporations, correctional officers of state correctional facilities, employees of state correctional facilities who have direct contact with inmates, correctional officers at multiple county detention centers (including Calvert, Carroll, and Washington counties), employees of the Intelligence and Investigative Division of the Department of Public Safety and Correctional Services, and communications officers at certain county control centres [12]Verified Maryland Labor and Employment Code §3-702 — Lie Detector Tests (2024)
Confirms employer prohibition on requiring polygraph tests, misdemeanor penalties, and detailed exemptions for law enforcement and corrections.

The Maryland State Police routinely administers polygraph examinations as part of its pre-employment screening process using a structured applicant polygraph screening booklet that covers personal background information, criminal history, financial matters, and substance use [6]Verified Maryland State Police Polygraph Unit — Commonly Asked Questions
Confirms the three-phase polygraph examination process, voluntary nature of testing, and quality control procedures used by Maryland State Police. All examinations conducted by the Maryland State Police Polygraph Unit are quality-controlled, meaning each test is independently scored by another polygraph examiner and the unit director [6]Verified Maryland State Police Polygraph Unit — Commonly Asked Questions
Confirms the three-phase polygraph examination process, voluntary nature of testing, and quality control procedures used by Maryland State Police. For those preparing for a law enforcement polygraph, our Secret Service polygraph screening guide provides insight into the federal screening process.

Federal EPPA Protections in Maryland

Maryland employees also benefit from the federal Employee Polygraph Protection Act (EPPA) of 1988, which provides an additional layer of protection against employer-mandated polygraph testing in the private sector [13]Verified Employee Polygraph Protection Act (EPPA) — Maryland — J. J. Keller Compliance Network
Confirms Maryland does not have state-level polygraph examiner licensing requirements; examiners must meet federal requirements at 29 CFR 801.26. The EPPA generally prevents private employers from using polygraph tests for pre-employment screening or during employment, with limited exceptions for certain security-related industries and ongoing investigations involving economic loss [13]Verified Employee Polygraph Protection Act (EPPA) — Maryland — J. J. Keller Compliance Network
Confirms Maryland does not have state-level polygraph examiner licensing requirements; examiners must meet federal requirements at 29 CFR 801.26.

Maryland does not have state-level polygraph examiner licensing requirements [13]Verified Employee Polygraph Protection Act (EPPA) — Maryland — J. J. Keller Compliance Network
Confirms Maryland does not have state-level polygraph examiner licensing requirements; examiners must meet federal requirements at 29 CFR 801.26. Examiners operating in Maryland must meet federal requirements outlined at 29 CFR 801.26 [13]Verified Employee Polygraph Protection Act (EPPA) — Maryland — J. J. Keller Compliance Network
Confirms Maryland does not have state-level polygraph examiner licensing requirements; examiners must meet federal requirements at 29 CFR 801.26. When selecting a polygraph examiner in Maryland, it is essential to verify that the examiner has completed an accredited training programme recognised by the American Polygraph Association. For more details, see our guide on Maryland polygraph services and licensing requirements.

Sex Offender Supervision and PCSOT Programs

Maryland law specifically incorporates polygraph examinations into the supervision of sex offenders under Criminal Procedure Code §11-725, which establishes sexual offender management teams [14]Verified Maryland Criminal Procedure Code §11-725 — Sexual Offender Management Teams (2024)
Confirms Maryland law requires polygraph examiner on sexual offender management teams for lifetime supervision. These teams must include a polygraph examiner with "recognized expertise in sexual offender-specific polygraph examination" among their members [14]Verified Maryland Criminal Procedure Code §11-725 — Sexual Offender Management Teams (2024)
Confirms Maryland law requires polygraph examiner on sexual offender management teams for lifetime supervision. The teams submit progress reports on each person under supervision to the sentencing court every six months [14]Verified Maryland Criminal Procedure Code §11-725 — Sexual Offender Management Teams (2024)
Confirms Maryland law requires polygraph examiner on sexual offender management teams for lifetime supervision.

Under §11-723, lifetime sexual offender supervision conditions may include "requiring a person to take regular polygraph examinations" [15]Verified Maryland Criminal Procedure Code §11-723 — Lifetime Sexual Offender Supervision (2024)
Confirms lifetime sexual offender supervision conditions may include requiring regular polygraph examinations. Post-conviction sex offender testing (PCSOT) programmes in Maryland typically encompass four types of examinations: instant offence examinations verifying details of the convicted crime, sexual history disclosure examinations revealing the offender's complete history, maintenance examinations monitoring compliance with supervision conditions, and sexual offence monitoring examinations checking for new offending behaviour [16]Verified APA Model Policy for Post-conviction Sex Offender Testing (PCSOT)
Confirms the four basic types of PCSOT examinations: instant offense, sexual history disclosure, maintenance, and sexual offense monitoring. These programmes are instrumental in maintaining public safety and supporting offender rehabilitation.

For attorneys representing clients in sex offence cases, understanding the role of polygraph testing in supervision is essential. Our guide to polygraph for sexual assault defense covers the intersection of polygraph testing with defence strategy.

Defense Attorney Strategy and Plea Negotiations

Despite the per se exclusion rule in Maryland criminal trials, polygraph testing remains one of the most valuable investigative tools available to defence attorneys. A favourable polygraph result can provide significant leverage in plea negotiations, potentially persuading prosecutors to reconsider charges, agree to reduced charges, or recommend more favourable sentencing [17]Verified Department of Public Safety and Correctional Services v. Scruggs, 79 Md. App. 312, 556 A.2d 736 (1989)
Confirms Maryland judiciary's well-documented distrust of polygraph evidence, including that even stipulations between parties cannot override exclusion rule and that polygraph results are used in defense negotiations. Defence attorneys frequently use polygraph results during discussions with prosecutors, even though those results would be inadmissible if the case proceeded to trial [17]Verified Department of Public Safety and Correctional Services v. Scruggs, 79 Md. App. 312, 556 A.2d 736 (1989)
Confirms Maryland judiciary's well-documented distrust of polygraph evidence, including that even stipulations between parties cannot override exclusion rule and that polygraph results are used in defense negotiations.

The strategic value of polygraph testing in the defence context cannot be overstated. When a credible, examiner trained to APA standards produces a result indicating no deception, prosecutors must weigh the risk of proceeding to trial against a defendant who has demonstrated a willingness to subject himself to scientific scrutiny. This dynamic is particularly powerful in cases where the evidence is circumstantial or dependent on witness credibility. For a deeper understanding of how a deceptive polygraph result affects the legal process, consult our detailed guide.

Polygraph examinations can also help defence attorneys assess their own clients' truthfulness early in the case, allowing them to develop more effective defence strategies. If a client's account is confirmed by polygraph testing, the attorney can pursue the case with greater confidence and present a more compelling narrative to the prosecution.

Family Court and Civil Proceedings

While Maryland maintains strict exclusion of polygraph evidence in criminal trials, the rules are more flexible in civil and family court proceedings [18]Verified Admissibility of Polygraph Tests in Court — LegalMatch
Confirms polygraph tests are sometimes admissible in civil courts including divorce proceedings. Polygraph tests may sometimes be admissible in civil courts, including divorce proceedings when proving adultery or abuse, particularly when both parties consent to the examination [18]Verified Admissibility of Polygraph Tests in Court — LegalMatch
Confirms polygraph tests are sometimes admissible in civil courts including divorce proceedings. Courts have broader discretion in civil matters to admit evidence that might be excluded in criminal proceedings.

In custody disputes, polygraph testing can be especially valuable for establishing credibility on issues such as allegations of abuse, substance use, or parenting fitness. For a comprehensive overview of how polygraph evidence is handled in custody matters across the United States, see our polygraph in custody battles guide. Couples facing relationship trust issues may also find value in private polygraph testing — our guide on what to do when your partner wants a lie detector test provides practical advice.

To understand the differences between tests arranged privately and those ordered by the court, review our guide on private vs. court-ordered polygraph testing.

Law Enforcement Investigations

Maryland law enforcement agencies regularly use polygraph examinations as investigative tools to guide the direction of criminal investigations [17]Verified Department of Public Safety and Correctional Services v. Scruggs, 79 Md. App. 312, 556 A.2d 736 (1989)
Confirms Maryland judiciary's well-documented distrust of polygraph evidence, including that even stipulations between parties cannot override exclusion rule and that polygraph results are used in defense negotiations. The Maryland State Police operates a dedicated Polygraph Unit that conducts examinations for both investigative and applicant screening purposes [6]Verified Maryland State Police Polygraph Unit — Commonly Asked Questions
Confirms the three-phase polygraph examination process, voluntary nature of testing, and quality control procedures used by Maryland State Police. The unit emphasises that the polygraph examination is always voluntary and consists of three phases: a pre-test interview covering legal rights and background information, the in-test phase where reviewed questions are administered and physiological responses recorded, and a post-test interview discussing results [6]Verified Maryland State Police Polygraph Unit — Commonly Asked Questions
Confirms the three-phase polygraph examination process, voluntary nature of testing, and quality control procedures used by Maryland State Police.

The investigative use of polygraph is legally distinct from the evidentiary question. While results cannot be introduced at trial under the Hawkins per se rule, they can direct investigators toward productive leads, help identify persons of interest, and assist in eliminating suspects from an investigation. This investigative function has been recognised as valid even by courts that exclude polygraph evidence from trial [2]Verified Rawlings v. State, 7 Md. App. 611, 256 A.2d 704 (1969)
Confirms Maryland's first direct holding that polygraph evidence is inadmissible, establishing the foundational precedent. To understand how polygraph testing assists in DUI defence strategies, see our guide on polygraph after DUI accusation.

United States v. Scheffer (1998)

The U.S. Supreme Court's decision in United States v. Scheffer, 523 U.S. 303 (1998), was the first time the nation's highest court addressed polygraph admissibility [19]Verified United States v. Scheffer, 523 U.S. 303 (1998) — Supreme Court
Confirms the Supreme Court upheld per se exclusion of polygraph evidence in military courts and left admissibility decisions to individual jurisdictions. The Court upheld Military Rule of Evidence 707, which establishes a per se ban on polygraph evidence in military courts, finding it does not unconstitutionally abridge a defendant's Sixth Amendment right to present a defence [19]Verified United States v. Scheffer, 523 U.S. 303 (1998) — Supreme Court
Confirms the Supreme Court upheld per se exclusion of polygraph evidence in military courts and left admissibility decisions to individual jurisdictions. The Court acknowledged the lack of scientific consensus, noting that some studies found accuracy rates "in the range of 87 percent" while others suggested rates "little better than could be obtained by the toss of a coin" [19]Verified United States v. Scheffer, 523 U.S. 303 (1998) — Supreme Court
Confirms the Supreme Court upheld per se exclusion of polygraph evidence in military courts and left admissibility decisions to individual jurisdictions.

Critically, the Scheffer decision left the question of polygraph admissibility to individual jurisdictions, holding that a per se exclusion rule "is not an arbitrary or disproportionate means" of avoiding the collateral litigation that polygraph evidence inevitably entails [19]Verified United States v. Scheffer, 523 U.S. 303 (1998) — Supreme Court
Confirms the Supreme Court upheld per se exclusion of polygraph evidence in military courts and left admissibility decisions to individual jurisdictions. This means Maryland's per se rule stands on solid constitutional ground, but the decision does not preclude states from adopting more permissive approaches. The Scheffer ruling effectively created a national framework in which each state — including Maryland — determines its own approach to polygraph evidence.

Daubert v. Merrell Dow Pharmaceuticals (1993)

The U.S. Supreme Court's 1993 decision in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, fundamentally changed the landscape for scientific evidence admissibility nationwide [20]Verified Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993)
Confirms the Supreme Court established the Daubert framework for evaluating expert scientific testimony, superseding the Frye standard. The Court held that the Federal Rules of Evidence superseded the Frye "general acceptance" standard, establishing a more flexible reliability-based framework for evaluating expert testimony [20]Verified Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993)
Confirms the Supreme Court established the Daubert framework for evaluating expert scientific testimony, superseding the Frye standard. The Daubert factors — testability, peer review and publication, known error rate, and general acceptance — gave trial judges a structured framework for serving as gatekeepers of scientific evidence.

Maryland's adoption of Daubert in Rochkind (2020) brought these principles to bear on state-level proceedings [7]Verified Rochkind v. Stevenson, 471 Md. 1, 236 A.3d 630 (2020) — Court of Appeals Opinion
Confirms Maryland Court of Appeals retired Frye-Reed standard and adopted Daubert framework for expert testimony on August 28, 2020. For polygraph proponents, the Daubert framework offers a pathway for demonstrating that specific, validated polygraph techniques meet scientific reliability standards. Research published in peer-reviewed journals has documented accuracy rates between 87% and 97% for properly administered polygraph examinations using validated techniques [21]Verified The Admissibility of Polygraph Test Results — Park, Jung-Hun (2015)
Confirms research arguing polygraph testing demonstrates 91-97% accuracy and courts should reconsider categorical inadmissibility, which could form the basis for future admissibility challenges under the Daubert framework.

The Semrau Decision and Alternative Technologies

The Sixth Circuit's 2012 decision in United States v. Semrau established the first appellate precedent against brain-based deception detection, emphasising unreliable error rates and lack of real-world validation beyond laboratory settings [22]Verified fMRI Lie Detection Validity and Admissibility as Evidence in Court
Confirms the Sixth Circuit's Semrau decision established first appellate precedent against brain-based deception detection. This ruling is significant for Maryland practitioners because it demonstrates that even under the more flexible Daubert standard, courts apply rigorous scrutiny to novel deception detection technologies.

The Semrau decision underscores the importance of established, validated techniques when seeking admissibility. While newer technologies such as fMRI-based lie detection have struggled to gain judicial acceptance, traditional polygraph examination benefits from decades of field research, peer-reviewed validation studies, and widespread professional use [23]Verified Flickering Admissibility: Neuroimaging Evidence in the US Courts
Confirms U.S. courts apply greater skepticism to functional deception detection technologies like fMRI while routinely admitting structural neuroimaging. Courts have applied greater scepticism to functional deception detection technologies like fMRI while maintaining familiarity with traditional polygraph methods [23]Verified Flickering Admissibility: Neuroimaging Evidence in the US Courts
Confirms U.S. courts apply greater skepticism to functional deception detection technologies like fMRI while routinely admitting structural neuroimaging.

Modern Accuracy Rates and Validation Research

Modern polygraph research demonstrates significant advances in accuracy and reliability compared to the techniques available when Maryland courts first addressed polygraph admissibility in the 1960s. Research published in peer-reviewed journals has documented accuracy rates as high as 97% for properly administered examinations using validated techniques [21]Verified The Admissibility of Polygraph Test Results — Park, Jung-Hun (2015)
Confirms research arguing polygraph testing demonstrates 91-97% accuracy and courts should reconsider categorical inadmissibility. The American Polygraph Association reports that validated polygraph techniques achieve accuracy rates of 90% or higher, with some studies showing 93-95% accuracy on specific examination types [24]Verified Maryland Polygraph FAQ — Deception Detection Specialists
Confirms APA-validated polygraph techniques test with accuracy of 90% with some studies showing 93-95% accuracy.

These advances are driven in part by the transition from analogue to computerised polygraph instruments, which allow for more precise measurement and standardised scoring algorithms. The evolution of how software changed the lie detector test has been central to improving both reliability and consistency. Research also shows that mock jurors do not blindly accept polygraph evidence; rather, they demonstrate a critical but balanced assessment when evaluating such evidence [25]Verified The admissibility of polygraph evidence in court: Some empirical findings
Confirms that mock jurors do not blindly accept polygraph evidence; shifts in guilt ratings were significant but not overwhelming.

The Impact of Juror Perception Research

A common argument against polygraph admissibility is that jurors will give polygraph evidence undue weight. However, empirical research conducted by Ronald J. Heslegrave and published in Law and Human Behavior found that mock jurors do not blindly accept polygraph evidence [25]Verified The admissibility of polygraph evidence in court: Some empirical findings
Confirms that mock jurors do not blindly accept polygraph evidence; shifts in guilt ratings were significant but not overwhelming. While guilt ratings shifted significantly in the presence of exculpatory polygraph evidence, the shifts were not overwhelming — suggesting that jurors are capable of critically evaluating polygraph evidence alongside other trial evidence [25]Verified The admissibility of polygraph evidence in court: Some empirical findings
Confirms that mock jurors do not blindly accept polygraph evidence; shifts in guilt ratings were significant but not overwhelming.

This research is particularly relevant to future Daubert challenges in Maryland, as it directly addresses one of the traditional justifications for the per se exclusion rule: the concern that jurors will be unduly swayed by polygraph evidence. Studies on credibility assessment and deception detection in courtrooms provide additional context for understanding how factfinders evaluate different forms of evidence.

Concealed Information Test Research

In addition to the traditional comparison question technique, research on the Concealed Information Test (CIT) has expanded the scientific foundation for polygraph-related evidence [26]Verified Admissibility and Constitutional Issues of the Concealed Information Test in American Courts
Foundational research relevant to constitutional dimensions of polygraph admissibility in American courts. The CIT operates on different principles than traditional deception detection — it tests whether a subject possesses knowledge of crime-related details rather than directly measuring deception. Constitutional dimensions of the CIT in American courts have been explored in foundational research examining how this technique interacts with existing admissibility frameworks [26]Verified Admissibility and Constitutional Issues of the Concealed Information Test in American Courts
Foundational research relevant to constitutional dimensions of polygraph admissibility in American courts.

The CIT has particular promise in the post-Daubert landscape because it is grounded in well-established psychophysiological principles of orienting response and memory detection [27]Verified The CIT in the courtroom: Legal aspects
Foundational research on the legal aspects of the Concealed Information Test in courtroom settings. As Maryland continues to develop its Daubert jurisprudence, the CIT may present a distinct pathway for introducing polygraph-related evidence that avoids some of the traditional objections to comparison question techniques.

Choosing a Qualified Examiner

Because Maryland does not have state-level licensing requirements for polygraph examiners [13]Verified Employee Polygraph Protection Act (EPPA) — Maryland — J. J. Keller Compliance Network
Confirms Maryland does not have state-level polygraph examiner licensing requirements; examiners must meet federal requirements at 29 CFR 801.26, selecting a qualified professional requires careful attention to training and credentials. Look for examiners who have completed accredited training programmes recognised by the American Polygraph Association, hold current APA membership, use validated examination techniques, and maintain ongoing professional education. Accredited schools such as the American International Institute of Polygraph (AIIP), PEAK Credibility Assessment Training, and the Academy for Scientific Investigative Training (ASIT) produce well-qualified examiners.

To guard against unreliable results, be aware of the risks associated with unqualified examiners. Our guide on fake polygraph results and how to verify them explains how to confirm the authenticity of examination results. For those interested in pursuing a career in polygraph examination, comprehensive guidance is available on our career page.

The Testing Process

A professional polygraph examination in Maryland typically follows a standardised three-phase process [6]Verified Maryland State Police Polygraph Unit — Commonly Asked Questions
Confirms the three-phase polygraph examination process, voluntary nature of testing, and quality control procedures used by Maryland State Police. The pre-test interview establishes rapport, explains legal rights and the voluntary nature of the examination, reviews medical and psychological background, discusses the subject's knowledge of the matter being investigated, and explains how the polygraph instrument works [6]Verified Maryland State Police Polygraph Unit — Commonly Asked Questions
Confirms the three-phase polygraph examination process, voluntary nature of testing, and quality control procedures used by Maryland State Police. During the in-test phase, the examiner reviews all test questions with the subject, conducts a demonstration test to assess suitability, and then administers several test charts using the reviewed questions — there are no surprise questions [6]Verified Maryland State Police Polygraph Unit — Commonly Asked Questions
Confirms the three-phase polygraph examination process, voluntary nature of testing, and quality control procedures used by Maryland State Police.

The post-test interview involves discussion of results and the examiner's opinion. For examinations conducted by the Maryland State Police, all tests undergo quality control with independent scoring by another examiner and the unit director [6]Verified Maryland State Police Polygraph Unit — Commonly Asked Questions
Confirms the three-phase polygraph examination process, voluntary nature of testing, and quality control procedures used by Maryland State Police. The entire process typically takes two to three hours, with results available within 24-48 hours for private examinations. For more on what to expect and how to prepare, visit our lie detector test cost in Maryland guide.

Scheduling a Polygraph Test in Maryland

Whether you need a polygraph for a criminal defence investigation, family court matter, personal relationship issue, or pre-employment screening, LieDetectorTest.com offers professional polygraph services throughout Maryland. All examinations are conducted by examiners trained to APA standards using validated techniques that meet the highest professional standards.

The value of polygraph testing in Maryland extends well beyond the courtroom. Even where results are inadmissible as formal evidence, they serve critical functions in guiding investigations, supporting plea negotiations, resolving family disputes, and providing peace of mind in personal matters. For individuals in neighbouring states, our guides on private polygraph testing in New Jersey and private polygraph tests in Michigan provide additional regional information.