Identification of the best interview technique for polygraph examinations

The present research explores the best interview and interrogation techniques to obtain effective and conclusive information in the framework of a polygraph test. The PEACE method and the Reid and SCAnR techniques are compared, and the different types of interviews (structured, semi-structured and
cognitive) are taken into account. The research is mixed: in a first phase, the techniques under study are analyzed with the categories of analysis: rapport, admissions, duration, false positives/false negatives, inconclusive evidence, types of interview, credibility assessment and flexibility. Subsequently, surveys are applied to expert polygraphists of the Credibility and Reliability Group of
the Police Intelligence Directorate, to finally analyze in a theoretical-practical way the technique with the lowest margin of error. As a result, the relevance of the rapport to obtain significant information in a polygraph examination is highlighted. The relevance of the SCAnR technique is underlined, although
78% of the respondents do not implement it due to its requirement in terms of specific knowledge. The PEACE technique is preferred by more than 70%, and is endorsed for its flexibility and compliance with analytical criteria. Caution in the use of the Reid technique stands out, preferred by 22% of the professionals, mainly among experienced male polygraphists, despite its rigidity.