The author(s) shown below used Federal funds provided by the U.S. Department of Justice and prepared the following final report: Document Title: Assessing the Validity of Voice Stress Analysis Tools in a Jail Setting Author(s): Kelly R. Damphousse ; Laura Pointon ; Deidra Upchurch ; Rebecca K. Moore Document No.: 219031 Date Received: June 2007 Award Number: 2005-IJ-CX-0047 This report has not been published by the U.S. Department of Justice. To provide better customer service, NCJRS has made this Federally- funded grant final report available electronically in addition to traditional paper copies. Opinions or points of view expressed are those of the author(s) and do not necessarily reflect the official position or policies of the U.S. Department of Justice. This document is a research report submitted to the U.S. Department of Justice. This report has not been published by the Department. Opinions or points of view expressed are those of the author(s) and do not necessarily reflect the official position or policies of the U.S. Department of Justice. Assessing the Validity of Voice Stress Analysis Tools in a Jail Setting Kelly R. Damphousse University of Oklahoma Laura Pointon University of Oklahoma Deidra Upchurch KayTen Research and Development and Rebecca K. Moore Oklahoma Department of Mental Health and Substance Abuse Services March 31, 2007 Acknowledgements: This research project was made possible through a grant from the National Institute of Justice (2005-IJ-CX-0047) to the Oklahoma Department of Mental Health and Substance Abuse Services. The report reflects the views of the research team and do not necessarily represent the official positions or policies of the United States Department of Justice or the Oklahoma Department of Mental Health and Substance Abuse Services. The research team gratefully acknowledges the assistance of John Whetsel, Oklahoma County Sheriff for allowing access to the Oklahoma County Jail. We also would like to thank Chief Bill Endler (CVSA) and Tom Winscher (V Worldwide) and the training staff at CVSA and LVA who were so helpful throughout the entire project. We also thank Christine Crossland and the external reviewers whose critical insights greatly improved this report. Finally, we acknowledge the participation of the research subjects, without whom the project would not have been possible. This document is a research report submitted to the U.S. Department of Justice. This report has not been published by the Department. Opinions or points of view expressed are those of the author(s) and do not necessarily reflect the official position or policies of the U.S. Department of Justice. Table of Contents Page Number Abstract..................................................................................................................................i Executive Summary...............................................................................................................ii Narrative 1. Introduction and Project Background ....................................................................1 2. Review of relevant literature..................................................................................8 a. VSA Computer Programs ..........................................................................8 b. VSA Evaluations........................................................................................19 3. Research design and Analysis Strategy .................................................................25 a. Research Design.........................................................................................26 b. Analysis Strategy .......................................................................................35 4. Findings..................................................................................................................41 a. Evaluating Validity of VSA Software for Deception Detection................45 b. Evaluating the Reliability of the VSA Programs.......................................69 c. Bogus Pipeline Effect.................................................................................82 5. Conclusions and Implications for Policy and Practice ..........................................87 6. Bibliography/References........................................................................................101 7. Appendices a. Jail Officer/Research Associate Checklist for VSA...................................106 b. VSA Facesheet...........................................................................................108 c. CVSA Survey Form ...................................................................................109 d. LVA Survey Form .....................................................................................110 e. Verbal Consent Script ................................................................................111 f. Summary of Drug Testing ..........................................................................112 g. Tests Comparing Validity of VSA Programs for Deceptiveness Related to All Drugs Including Those Who Reported Marijuana Use but Tested Negative ....................................................................................114 h. Table Comparing CVSA and LVA data ....................................................116 This document is a research report submitted to the U.S. Department of Justice. This report has not been published by the Department. Opinions or points of view expressed are those of the author(s) and do not necessarily reflect the official position or policies of the U.S. Department of Justice. Assessing the Validity of Voice Stress Analysis Tools in a Jail Setting Abstract Manufacturers of Voice Stress Analysis (VSA) devices have suggested that their devices are able to measure deception with great accuracy, low cost, and little training. As a result, police departments across the country have purchased costly VSA computer programs with the intention of supplementing (or supplanting) the use of the polygraph at an estimated cost of more than $16,000,000. Previous VSA studies have been conducted using simulated deception in laboratory conditions. These earlier research projects suggest that VSA programs have the capacity to detect changes in vocal patterns as a result of induced stress. To date, however, no published research studies have demonstrated that VSA programs can distinguish between “general” stress and the stress related to being deceptive. The goal of this study was to test the validity and reliability of two popular VSA programs (LVA and CVSA) in a “real world” setting. Questions about recent drug use were asked of a random sample of arrestees in a county jail. Their responses and the VSA output were compared to a subsequent urinalysis to determine if the VSA programs could detect deception. Both VSA programs show poor validity - neither program efficiently determined who was being deceptive about recent drug use. The programs were not able to detect deception at a rate any better than chance. The data also suggest poor reliability for both VSA products when we compared expert and novice interpretations of the output. Correlations between novices and experts ranged from 0.11 to 0.52 (depending on the drug in question). Finally, we found that arrestees in this VSA study were much less likely to be deceptive about recent drug use than arrestees in a non-VSA research project that used the same protocol (i.e., the ADAM project). This finding provides support for the “bogus pipeline” effect. i This document is a research report submitted to the U.S. Department of Justice. This report has not been published by the Department. Opinions or points of view expressed are those of the author(s) and do not necessarily reflect the official position or policies of the U.S. Department of Justice. Voice Stress Analysis in a Jail Setting Assessing the Validity of Voice Stress Analysis Tools in a Jail Setting Executive Summary Purpose. • Manufacturers of Voice Stress Analysis (VSA) devices have suggested that their devices are able to measure deception with great accuracy, low cost, and little training. • The devices claim to measure the physiological effect experienced by subjects who try to deceive. • Developers suggest that the effect of this stress on the vocal cords is measurable and deception can be observed as output using their product. • There are no known tests of the ability of VSA to determine deception among arrestees. • This project assesses the validity of two of the more popular VSA tools currently on the market - Layered Voice Analysis (LVA) and Computer Voice Stress Analyzer (CVSA) among a group of arrestees. • Each of the VSA programs was tested to assess: (1) Validity – can the instruments correctly detect deception? (2) Reliability – How do novices and experts compare in interpretation of output? (3) The “bogus pipeline” effect – Do individuals deceive less likely when they think that the interviewer “knows” that they are being deceptive. Method. • We interviewed a random sample of arrestees in a county jail during the booking process to simulate the stress of a detention-related interview. • We used the VSA programs to ask about recent drug use. • Each survey was followed by a urinalysis to determine if the subject was being deceptive. • The resulting data allowed for a comparison between “actual deception” and the VSA output. ii This document is a research report submitted to the U.S. Department of Justice. This report has not been published by the Department.