Validated Polygraph Techniques


The polygraph techniques listed below met the scientific requirements of the American Polygraph Association to be classified as Evidentiary Polygraph Techniques which require a minimum criterion accuracy of 90% with an inconclusive rate not to exceed 20%.

Three types of studies were used to validate these polygraph techniques:

Field study

Uses actual real-life polygraph examinations whose results are confirmed with acceptable scientific or judicial evidence.

Laboratory study

Uses a mock crime with participants assigned the role of Guilty or Innocent examinees.

Monte Carlo study

Uses a statistical method that is based on repeated random sampling of data from independent source of confirmed field cases that is used to estimate polygraph decision accuracy.

A full discussion of the merits of field versus laboratory studies entitled "Guiding Principles and Benchmarks for the Conduct of Validity Studies of Psychophysiological Veracity Examinations Using The Polygraph" is available for review on this website.

Evidentiary Polygraph Techniques

 

Matte Quadri-Track Zone Comparison Technique

Raw Data for Matte Quadri-Track Zone Comparison Technique

Integrated Zone Comparison Technique - (Horizontal Scoring System)

Utah Zone Comparison Technique - Canadian Police College, RCMP.

  • Honts, Hodes, Raskin, 1985. Laboratory Study published in Applied Psychology, Vol. 70, Nr. 1.
    Sample Nr. 38. Accuracy: 83.3% without Inconclusives. 23.7% Inconconclusives.
  • Driscoll, Honts, Jones 1987. Laboratory Study published in Polygraph, Vol.16, Nr. 3.
    Sample Nr.40. Accuracy: 100% without Inconclusives. 10% Inconclusives.
  • Honts 1996. Field Study published in Journal of General Psychology, Vol. 123.
    Sample Nr. 32. Accuracy: 96.9% without Inconclusives. 21% Inconclusives.

Utah Zone Comparison Technique – Probable Lie Test

  • Kircher, Raskin, 1988. Laboratory Study published in Applied Psychology, Vol. 73, Nr. 2.
    Sample Nr. 100. Accuracy: 93.5% without Inconclusives. 7% Inconclusives.
  • Honts, Raskin, Kircher, 1987. Laboratory Study published in Psychophysiology, Vol. 1, Nr. 3.
    Sample Nr. 20. Accuracy: 88.9% without Inconclusives. 15% Inconclusives.

Federal You-Phase - (Empirical Scoring System)

  • Nelson 2011. Monte Carlo Study published in Polygraph, Vol. 40.
    Sample Nr. 100. Accuracy 89.7% without Inconclusives. 9.6% Inconclusives.
  • Nelson, Handler, Blalock, Cushman 2012. Field Study. (Polygraph, in Press).
    Sample Nr. 22. Accuracy 90.6% without Inconclusives. 23.5% Inconclusives.

Utah Zone Comparison Technique – Directed Lie Test

  • Honts, Raskin 1988. Field Study published in Journal of Police Science and Administration,
    Vol. 16, Nr. 1. Sample Nr. 25. Accuracy: 95.8% without Inconclusives. 7.7% Inconclusives.
  • Horowitz, Kircher, Honts, Raskin 1997. Laboratory Study published in Psychophysiology,
    Vol. 34, Nr. 1. Sample Nr. 30. Accuracy: 85.6% without Inconclusives. 6.7% Inconclusives.

Backster Zone Comparison Technique

The Backster Zone Comparison Technique from which all other Zone Comparison Techniques originate is undergoing further validation that is expected to raise its standing as an evidentiary technique. The following studies reflect its current validation status.

  • Nelson, Handler, Adams, Backster (2012). Survey of Reliability and Criterion Accuracy of Backster Numerical Scores of You-Phase Exams from Confirmed Field Investigations. Published in Polygraph, Vol. 41, Nr. 2. Sample Nr. 22. Accuracy 82.8% without Inconclusives, 11.7% Inconclusives.
  • Nelson (2012). Monte Carlo Study of Criterion Validity of Backster You-Phase Examinations. Published in Polygraph, Vol. 41, Nr. 1. Sample Nr. 100. Accuracy 92.7% without Inconclusives, 32.1% Inconclusives.

NOTE: The Nelson, Handler, Adams, Backster 2012 study used field cases from a government agency, some of which used formats that deviated from the Backster Zone Comparison Technique protocol which resulted in an accuracy rate below the expected minimum 90% criterion accuracy required for classification as an evidentiary technique.

Army Modified General Question Technique (MGQT)

Notice: There are several other polygraph techniques currently in use in the public and private sector with accuracy rates that range from 87% to as low as 61%, the latter being the Army Modified General Question Technique (MGQT) whose accuracy rate in the identification of Truthful cases (25% correct) should be of concern to defense attorneys in particular. The following published research studies on the MGQT are listed below:

  • 1988 Field Study published in Polygraph, Vol. 28, Nr. 2: 149-175.
  • 2000 Field Study published in Polygraph. Vol. 29, Nr. 2: 185-194.
  • 1993 Laboratory Study published in Journal of Applied Psychology. Vol. 75, Nr. 5: 788-794. Reprinted in Polygraph, Vol. 23, Nr. 3, 195-218.

    MGQT accuracy for Deceptive cases: 97% correct. 7% Inconclusives.
    MGQT accuracy for Truthful cases: 25% correct. 35% Inconclusives.
    Overall accuracy. 61% correct without Inconclusives. 21% Inconclusives.
    Source: Polygraph, Vol. 35, Nr. 3: 149-155, 2006.