SCAN is largely driven by 12 criteria: results from sexual abuse statements

Abstract

Scientific Content Analysis (SCAN) is increasingly used by investigative authorities to evaluate the credibility of statements made by witnesses and suspects. SCAN, however, lacks a well-defined list of criteria, and does not involve a standardised scoring system. In the current study, we investigated which SCAN criteria are represented in actual statements. To this end, we analysed 82 sexual abuse cases of the Dutch police in which SCAN had been applied. Two independent coders scored the presence of various SCAN criteria in the: (1) written statements from victims, suspects, and witnesses; and also looked at the (2) recommendations for follow-up investigations that were derived from SCAN. Results showed that SCAN is primarily driven by 12 criteria. Results also indicated a low inter-rater agreement for most SCAN criteria, suggesting SCAN is insufficiently developed as a forensic tool. Still, the 12 criteria can be used as a starting point for future research on their psychometric properties.

Keywords:

• lie detection
• scientific content analysis
• verbal cues

Acknowledgement

This research was funded by a grant from the Ministry of the Interior and Kingdom Relations of the Netherlands.

Notes

1. High correlations were expected as differences between coders merely reflected counting errors.

2. No McNemar statistic could be computed, because one of the variables showed no variation.