ported by the U.S. Department of Defense (DoD) Polygraph Program (2000:4 of 14) on the cases in which significant information was uncovered during DoD counterintelligence-scope polygraph examinations covered in the report:

It should be noted that all these individuals had been interviewed previously by security professionals and investigated by other means without any discovery of the information obtained by the polygraph examination procedure. In most cases, the information was elicited from the subject in discussion with the examiner [italics added].

There is no scientific evidence on the ability of the polygraph to elicit admissions and confessions in the field. However, anecdotal reports of the ability of the polygraph to elicit confessions are consistent with research on the “bogus pipeline” technique (Jones and Sigall, 1971; Quigley-Fernandez and Tedeschi, 1978; Tourangeau, Smith, and Rasinski, 1997). In bogus pipeline experiments, examinees are connected to a series of wires that are in turn connected to a machine that is described as a lie detector but that is in fact nonfunctional. The examinees are more likely to admit embarrassing beliefs and facts than similar examinees not connected to the bogus lie detector. For example, in one study in which student research subjects were given information in advance on how to respond to a classroom test, 13 of 20 (65 percent) admitted receiving this information when connected to the bogus pipeline, compared to only 1 of 20 (5 percent) who admitted it when questioned without being connected (Quigley-Fernandez and Tedeschi, 1978).

Admissions during polygraph testing of acts that had not previously been disclosed are often presented as evidence of the utility and validity of polygraph testing. However, the bogus pipeline research demonstrates that whatever they contribute to utility, they are not necessarily evidence of the validity of the polygraph. Many admissions do not depend on validity, but rather on examinees’ beliefs that the polygraph will reveal any deceptions. All admissions that occur during the pretest interview probably fall into this category. The only admissions that can clearly be attributed to the validity of polygraph are those that occur in the posttest interview in response to the examiner’s probing questions about segments of the polygraph record that correctly indicated deception. We know of no data that would allow us to estimate what proportion of admissions in field situations fall within this category.

Even admissions in response to questions about a polygraph chart may sometimes be attributable to factors other than accurate psychophysiological detection of deception. For example, an examiner may probe a significant response to a question about one act, such as revealing classified information to an unauthorized person, and secure an admission of a



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