Prosecuting the ‘Psychological Set’: Polygraph’s Silver Bullet Unmasked?

The ‘success’ of a polygraph examination is predicated on the establishment of differential or emotional salience (a ‘psychological set’) with an examinee. This, according to polygraph proponents, guarantees that an examinee will respond appropriately during the administration of the in-test (questioning) phase of the polygraph examination. However, polygraph procedure, as prescribed by its governing body, the American Polygraph Association (APA), is a static clinical Westernised process that does not make any provision for human multiplicity (culture/ethnicity, idiosyncrasies, level of education, language proficiency, ideologies, and so forth). Identical (one size fits all) test procedures are applied across the board – a highly controversial methodology.

The objectives of this study were to explore the degree to which certain intentional and unintentional human behaviour modification strategies have the potential to counterbalance claimed polygraph probity from an ontological and discursive standpoint and expose disquiet (potential flaws) regarding polygraph theory in the context of the ‘psychological set’. This article, furthermore, seeks to create an awareness of polygraph’s epistemic ambivalence and provide food-for-thought regarding its unadulterated application.