A polygraph, or what’s commonly called a “lie detector test”, is a device or procedure that measures and records body responses like blood pressure, pulse, respiration, and skin conductivity while the participant is asked a series of questions. It is generally believed that a person’s physiological responses change when giving a truthful answer versus a false answer.

Use of Polygraph Examinations in the Workplace

It is not unheard of for a boss to ask their employee to submit to a polygraph examination if they believe the employee has done something dishonest. To prevent abuses on the part of employers, 1998 the United States enacted the Employee Polygraph Protection Act (“EPPA”). 1 The EPPA prohibits most private employers from using any lie detector test either for pre-employment screening or during the course of employment. 2 Specifically, employers are prohibited from: “(1) Requiring, requesting, suggesting or causing, directly or indirectly, any employee or prospective employee to take or submit to a lie detector test; (2) Using, accepting, or inquiring about the results of a lie detector test of any employee or prospective employee; and (3) Discharging, disciplining, discriminating against, denying employment or promotion, or threatening any employee or prospective employee to take such action for refusal or failure to take or submit to such test, on the basis of the results of a test, for filing a complaint, for testifying in any proceeding, or for exercising any rights afforded by the Act.” 3

However, these protections are not absolute; there are exemptions. Subject to restrictions, the EPPA permits polygraph tests to be administered to certain job applicants of security service firms (armored car, alarm, and guard) and of pharmaceutical manufacturers, distributors and dispensers. 4 Additionally, there is a limited exemption for ongoing investigations. An employer is permitted to request an employee submit to a lie detector test if (1) the test is administered in connection with an ongoing criminal investigation related to an economic loss to the employer’s business, (2) the employee had access to the property that was the subject of the investigation, (3) the employer has a reasonable suspicion that the employee was involved in the incident or activity under investigation, and (4) the employer issues a statement to the examinee, before the test, containing the grounds set forth in points 1-3. 5

The “under ongoing investigations exemption” also contains some caveats. The exemption will not apply if an employee is discharged, disciplined, denied employment or promotion, or otherwise discriminated against in any manner on the basis of the analysis of a polygraph test chart or the refusal to take a polygraph test, without additional supporting evidence. 6 In addition, throughout all phases of the “under ongoing investigations” test, the examinee shall be permitted to terminate the test at any time; shall not be asked needless or degrading questions; and shall not be asked about religious beliefs, political affiliations, sexual behaviors, or labor organizations. 7 The are additional requirements concerning notice provided pre-test to the examinee, the examinee’s right to ask questions, and a copy of the results must be provided to the examinee following the test. 8

If an employer violates any provisions of the EPPA, they may be subject to fines and other penalties. 9 The employer may also be civilly liable to the employee, in that the employee may bring a lawsuit seeking money damages against the employer who violates this law. 10 The employee may also seek relief such as employment, reinstatement, promotion, and the payment of lost wages and benefits. 11

Use of Polygraph Examinations in the Law

Lie detectors, and their applicability to trial proceedings have long been the subject of debate among scholars and courts alike. The issue of lie detector admissibility in a legal context first arose in the landmark D.C. Court of Appeals decision, Frye v. United States. There, the Court of Appeals held that the “systolic blood pressure deception test”, as it was referred, lacked scientific standing and recognition from psychological and physiological authorities and therefore the results of that test were excluded from trial. 12 Since Frye, courts across the country have take three general positions on the admissibility of polygraph result evidence. First, there is the traditional rule that the results of a lie detector test are inadmissible by either party as evidence to prove, or disprove a fact, or when related to the credibility of a witness. 13 Second, a minority of jurisdictions allow that a court has the discretion to accept lie detector evidence if the parties stipulate to the admission of the results prior to testing. 14 Third, a small number of jurisdictions give a judge the discretion to admit results without stipulation from the parties, but historically, this has happened so rarely it is considered an aberration when it has occurred. 15

The reason that polygraph examinations do not have more widespread acceptance within the legal community seems to be that there are serious questions concerning the accuracy of the results. In 2003, a National Research Council panel appointed to study the scientific validity of the polygraph found no evidence of polygraph validity. 16 The American Psychological Association has stated that “most psychologists agree that there is little evidence that polygraph tests can accurately detect lies.” 17 The United States Supreme Court has recognized that in the courtroom, “the jury is the lie detector” and that “there is simply no consensus that polygraph evidence is reliable.” 18

  1. 29 USC § 2001 et seq.
  2. 29 C.F.R. § 801.1
  3. 29 C.F.R. § 801.4
  4. 29 USC § 2006
  5. Id.
  6. 29 USC § 2007
  7. Id.
  8. Id.
  9. 29 USC § 2005
  10. Id.
  11. 29 C.F.R. § 801.40
  12. Frye v. United States, 293 F. 1013 (D.C. Cir. 1923)
  13. McCormick on Evidence § 206.3, Psychology – Detection of Deception – Admissibility of lie-detector results (8th Ed.)
  14. Id.
  15. Id.
  16. R. Adelson, The polygraph in doubt, American Psychological Association, Monitor on Psychology (July/August 2004), https://www.apa.org/monitor/julaug04/polygraph
  17. The Truth About Lie Detectors (aka Polygraph Tests), American Psychological Association (August 5, 2004), https://www.apa.org/research/action/polygraph
  18. U.S. v. Scheffer, 523 U.S. 303 (1998)