The assessment of physiological parameters of the innocent subjects in the SPOT in the presented cases has its limits, while a comparison of these parameters with the charts of the perpetrators causes doubts as to the methodological soundness (lack of a sufficient number of cases). There are as many as four reasons hindering the assessment.
First of all, the number of presented charts of the innocent subjects is small; they are practically isolated cases and with tests featuring mainly names (given names, pseudonyms).
Secondly, I did not repeat the SPOT if it did not cause any reaction and at the same time the preliminary assessment of the CQT charts was positive for the subjects. Th is makes it impossible to compare physiological parameters of the subject in at least two SPOT charts in order to assess the evolution of the emotional activation. The parameters recorded during a SPOT were compared with the fi rst CQT chart, but this article does not present them.
Another problem results from the fact that the category of the ‘innocent’ includes the charts of two subjects (the witness of the behaviour of the possible perpetrator after the murder and the instigator of a murder). I included them in the groups of the ‘innocent’ only because the version before the examination assumed that they were the murderers, while their reactions to the control questions in the CQT were greater than those to the fundamental relevant question (‘Did you do it?’). As I mentioned above, physiological parameters of the two men in the consecutive CQT charts hinted at intensifi cation of emotions and the subjects themselves also displayed external manifestations of emotions. In principle, their charts should be presented in the group of ‘the perpetrators’. Although the manifestations of emotions were distinct, their assessment was subjective – and it cannot be verifi ed. Both subjects interfered with the examination: one refused to have his blood pressure and pulse recorded and the other interrupted the examination. This behaviour is typical for ‘the perpetrators’. Both subjects were involved in the cases, but not in the way the investigators had originally assumed. Let me add here that this is my opinion and it has not been backed by legal decisions.
Physiological parameters of the innocent subjects presented in the SPOT charts can only be assessed visually, because the Lafayette polygraphs which I used did not record them digitally. A visual assessment is not precise and to great extent subjective. Only one parameter – the pulse rate – lends itself to digital assessment, but with the reservations mentioned above.
This paper involves fifty-one re-examinations of original polygraph tests that resulted in conflicted outcomes and examinations where deliberate distortions were believed to have been employed. The Polygraph Validation Test (PVT) was successfully employed in these re-examinations to rectify the original problems and/or confirm attempts by examinees at countermeasures or augmentations.