Interviewing techniques and the assessment of statement credibility

Abstract The objective of this study is the development of an applicable comprehensive questioning and statement analysis procedure. One hundred and thirty‐six male residents of the Wynne Unit of the Texas Department of Criminal Justice—Institutional Division (TDCJ—ID) witnessed a staged theft, and provided testimony. Interview formats followed semi‐standardized scripts derived from Structured Interview, Inferential Interview and Cognitive Interview techniques. Participants were randomly assigned to one of six experimental conditions in a 2(honesty of reporting) × 3(interview technique) matrix. Results found a 62% classification accuracy for the Structured Interview, 68% for the Cognitive Interview and 82% for the Inferential Interview, when comparisons were made between treatment phases of each interview condition. When responses given to each interview segment were analysed, 83% of the Structured Interview transcripts were correctly identified, as were 91% of the Inferential and 92.9% of the Cognitive Interview statements. The desire to prevaricate while escaping detection produced statements which were systematically different from honest reporting, as seen in the variables of coherence, response length, type‐token ratio, and verbal hedges. These results indicate a potential forensic utility for strategies which attempt to detect deception through a combination of qualitative and quantitative statement characteristics, and underscore the need for systematic, question‐by‐question analysis of eyewitness statements. Copyright © 2002 John Wiley & Sons, Ltd.