A Field Study on Polygraph Accuracy

A field study on the validity of the Quadri-Track Zone Comparison Technique☆
Daniel J. Mangan ⁎, Thomas E. Armitage, Gregory C. Adams
8 Warren Way, Amherst, NH 03031, United States
A R T I C L E I N F O A B S T R A C T
Article history:
Received 4 November 2007
Received in revised form 18 February 2008
Accepted 3 March 2008

This field study tested and demonstrated the validity and reliability of the Quadri-Track Zone Comparison
Technique designed for specific Single-Issue Psychophysiological Veracity (PV) examinations using the
polygraph, using one hundred and forty confirmed real-life cases from a private polygraph firm under
contract with a metropolitan police department. The Quadri-Track Zone Comparison Technique's unique
Inside Track accurately increased the scores for the innocent by 43.6% and the guilty by 37.1% thereby
reducing the overall inconclusive rate from 19.5% to 1.4%, which effectively remedies the major cause (Fear/
Hope of Error) of inconclusive results in single-issue polygraph tests. The Quadri-Track Zone Comparison
Technique correctly identified 100% of the innocent as truthful with no inconclusives and no errors. It further
correctly identified 97.8% of the guilty as deceptive and 2.2% as inconclusive, with no errors. Inconclusives
excluded, the Quadri-Track Zone Comparison Technique was 100% accurate in the identification of the
innocent and the guilty. Inconclusives included, the utility rate was 98.6%. Blind scoring of polygraph charts
showed extremely high correlations for the individual and total scores with a combined accuracy of 98.3%.
© 2008 Elsevier Inc. All rights reserved.
1. Background of the Quadri-Track ZCT
This field study is the second published research on the validity of
the Quadri-Track Zone Comparison Technique (ZCT). The Quadri-Track
ZCT was initially developed in 1977 by James Allan Matte as a result of
field experiments designed to resolve the problem of false positives1
in psychophysiological veracity (PV) examinations using the polygraph
in a “zone comparison” test. The zone comparison test is a
polygraph technique developed by Cleve Backster in 1960 [3,12] that
encompasses three zones (black, red and green)2, two of which (red
and green) are compared and quantified for a determination of truth
or deception. Since Backster's development of the technique, zone
comparison polygraph tests in various formats have comprised the
vast majority of polygraph tests conducted in both the private and
government sectors. Generally speaking, the zone comparison polygraph
technique remains the standard operating method in polygraph
circles world wide.
Physiology & Behavior 95 (2008) 17–23
☆ The authors wish to express their gratitude to James Allan Matte for permission to
use his illustrations in Tables 1 and 2.
⁎ Corresponding author. Tel.: +1 603 801 5179; fax: +1 603 886 0001.
E-mail address: [email protected] (D.J. Mangan).
1 A false positive occurs when a truthful examinee is erroneously identified as
deceptive regarding the relevant issue. A false negative occurs when a deceptive
examinee is erroneously identified as truthful regarding the relevant issue. Fear of error
by an innocent examinee can cause an autonomic response on the relevant questions
that mimic deception [8,19].
2 The black zone consists of symptomatic questions designed to gain the examinee's
confidence regarding avoidance of unreviewed questions embracing outside issues.
The red zone consists of relevant questions dealing with the issue for which the
examinee is being polygraphed. The green zone consists of control questions that are
designed to elicit a negative answer from the examinee to questions that encompass
unknown offenses or misdeeds during a period earlier than the time the alleged
offense was committed. Each control question is compared against its neighboring
relevant question for a determination of truth of deception.
0031-9384/$ – see front matter © 2008 Elsevier Inc. All rights reserved.
doi:10.1016/j.physbeh.2008.03.001