In my first article in this series on the polygraph, I introduced a bit of history about the "lie detector." Today I'll review some of the applications of these devices in the 20th century.

A report dated September 2006 on “Use of Polygraph Examinations in the Department of Justice” from the Office of the Inspector General of the Department of Justice reveals some applications:

“During fiscal years (FY) 2002 through 2005, Department components conducted over 49,000 polygraph examinations. The examinations were used for a variety of reasons, including making pre-employment and personnel security decisions; investigating criminal, administrative, and security violations; ensuring witness security; providing sex offender treatment; and providing operational support in examining or ‘vetting’ foreign task force members and validating intelligence sources.”

The American Polygraph Association (APoA) summarizes applications of the polygraph as follows:

“Among the many applications of the polygraph are: police applicant screening, evidentiary polygraphy, criminal asset location, sex offender management, counterintelligence screening, political asylum validation, pre-trial stipulation, counter-narcotics programs, and counter-terrorism programs. The polygraph continues to be a mainstay in criminal investigations… resolving a substantial number of cases every day from behind the scenes.”

One of the most controversial applications of the polygraph is in pre-employment screening.

Security officers in industry who are trying to strengthen pre-employment screening to improve security for their organizations in collaboration with their human resources teams should be cautious about recommending polygraph examinations as a primary or stand-alone criterion for accepting or rejecting candidates (the emphasis in this warning is critically important). A wide range of studies confirms that polygraph results cannot by themselves determine the trustworthiness of the people being examined.

The APoA elaborates:

“Preemployment Test Accuracy – To date, there has been only a limited number of research projects on the accuracy of polygraph testing in the pre-employment context, primarily because of the difficulty in establishing ground truth. However, since the same physiological measures are recorded and the same basic psychological principles may apply in both the specific issue and pre-employment examinations, there in no reason to believe that there is a substantial decrease in the accuracy rate for the preemployment circumstance. The few studies that have been conducted on pre-employment testing support this contention. While the polygraph technique is not infallible, research clearly indicates that when administered by a competent examiner, the polygraph test is one of the most accurate means available to determine truth and deception.”

M. E. Kabay, PhD, CISSP-ISSMP, specializes in security and operations management consulting services. CV online.