CCTV, Live and Videotapes: How Presentation Mode Affects the Evaluation of Witnesses
Abstract
Videotaped and closed circuit testimonies are often used in legal procedures, but little is known about the psychological effects of these courtroom technologies. The present thesis examines how different presentation modes affect observers’ perception, veracity assessment and memory. In Study I truth-telling and lying adult witnesses were interviewed. Mock jurors (N = 122) viewed the testimonies, either live or on video, and rated their perception and assessed the veracity of the witnesses’ statements. Live observers rated the witnesses’ appearance in more positive terms and assessed them as being more honest than did video observers. Furthermore, both live and video observers’ deception detection performance was at chance level (49.2% vs. 50.8%). Live observers incorrectly believed they had a better memory of the witnesses’ statements than video observers. Study ΙΙ was structurally similar to Study I (but used child witnesses). Mock jurors (N = 136) viewed truth-telling and lying children’s testimonies (either live or on video), rated their perception of the children and assessed the children’s veracity. Live observers rated the children’s statements as being more convincing than did video observers. The overall deception detection performance was 59.6%, which was significantly different from the level of chance. Live observers were better than chance, but not better than the video observers, in assessing veracity. Moreover, live observers believed they had a better memory of the children’s statements than video observers, and they also showed a significantly better memory performance. In Study III truth-telling and lying children were viewed and assessed by adult mock jurors (N = 240) either live, via two-way closed-circuit television (CCTV), or via pre-recorded video. The mock jurors rated their perception of the children’s testimonies and assessed the children’s veracity. The results showed that live observers perceived the children in more positive terms than did the CCTV observers, who in turn perceived the children in more positive terms than did the video observers. The observers’ overall deception detection accuracy was mediocre (58.3%). Study IV investigated the effects of different camera perspectives on adults’ perception and assessment of videotaped child testimonies. Truth-telling and lying children were interviewed and videotaped simultaneously by four cameras, each taking a different visual perspective (close-up shot/child only, medium shot/child only, medium shot/child and interviewer, long shot/child and interviewer). Mock jurors (N = 256) rated their perception of the children and assessed the veracity of the statements. Children seen in long shot were perceived in more positive terms, and children seen in close-up were perceived as having to think harder. The adult’s deception detection accuracy was at chance level. Taken together, the results showed that the presentation mode affected the observers’ perception of the witnesses’ testimonies. Thus, the thesis suggests that legal policy-makers should consider the outcome of psycho-legal research on different presentation modes when establishing and/or reforming standards for police interviews and courtroom procedures.
Parts of work
I. Landström, S., Granhag P.A., & Hartwig, M. (2005). Witnesses appearing live versus on video: Effects on observers' perception, veracity assessments and memory. Applied Cognitive Psychology, 19, 913-933.::doi::10.1002/acp.1131 II. Landström, S., Granhag, P.A., & Hartwig, M. (2007). Children’s live and videotaped testimonies: How presentation mode affects observers’ perception, assessment and memory. Legal and Criminological Psychology, 12, 333–347.::doi::10.1348/135532506X133607 III. Landström, S., & Granhag, P.A. (2007). In-Court vs. Out-of-Court Testimonies: Children’s Experiences and Adults’ Assessment. Manuscript submitted for publication. IV. Landström, S., & Granhag, P.A. (in press). Children’s truthful and deceptive testimonies: How camera perspective affects adult observers’ perception and assessment. Psychology, Crime and Law.
Degree
Doctor of Philosophy
University
Göteborgs universitet. Samhällsvetenskapliga fakulteten
University of Gothenburg. Faculty of Social Sciences
Institution
Department of Psychology
Disputation
Department of Psychology, Haraldsgatan 1, Göteborg, lecture hall F1, at 10.00
Date of defence
2008-05-16
Date
2008-04-29Author
Landström, Sara
Keywords
Presentation Mode
Live
Video
Two-way CCTV
Deception detection
Publication type
Doctoral thesis
ISBN
978-91-628-7480-3
ISSN
1101-718X
Series/Report no.
Doctoral Dissertation
Language
eng