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An Ecological Approach to Deception Detection. J. Pete Blair, Ph.D., Department of Criminal Justice, Texas State University Tim R. Levine, Ph.D., Department of Communication, Michigan State University. A test of skill. Some more. 40+ Years of the Traditional Approach.
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An Ecological Approach to Deception Detection J. Pete Blair, Ph.D., Department of Criminal Justice, Texas State University Tim R. Levine, Ph.D., Department of Communication, Michigan State University
40+ Years of the Traditional Approach • The primary theories are leakage based (Ekman, Zuckerman, Burgoon, DePaulo) • Based on these theories, the primary concern is identifying leakage and people’s ability to detect it. • The outcomes of this type of research have been: • Few behaviors reliably indicate deception, and those that do tend to exhibit small effect sizes (DePaulo et al., 2003) • People don’t know the cues to deception • People are only slightly (4%) better than chance at detecting deception and accuracy clusters normally around the mean (Bond & DePaulo, 2006) • There is little variance in judge ability, but enormous variance in sender credibility (Bond & DePaulo, 2008) • Training has a small effect (4%) on accuracy (Frank & Feeley, 2003)
40+ Years of the Traditional Approach • The results of the traditional approach are quite modest • And surprising! • Why? • Lack of realism (low stakes, sanctioned lies)? • Myopic focus on leakage? • In our opinion, there is a need for a new paradigm
Looking for Exceptions • Asch (1956) Line length studies • Milgram (1969) Obedience to authority • Park et al. (2002) How people really detect lies • “Reid” based series of studies • Hartwig et al. (2005 & 2006) – Strategic Use of Evidence • Why are these different? • We think that the answer is Context
Context • All communication occurs in a context • It is difficult to communicate without knowledge of the context • Most deception detection experiments are designed to strip context away because of a leakage focus • Context could provide information which assists in deception detection • We call these “Content in Context Cues” • Contradiction • Normative • Idiosyncratic
Our Big “Content in Context” Study • 6 Samples of Participants in 8 Runs • 3 sets of videos • 2 basic conditions (context/no context) • Context • 176 unique judges who made 2422 judgments • 75% accuracy (1% SE) • No Context • 237 unique judges who made 3132 judgments • 57% accuracy (1% SE) • Clearly context matters! • Blair, J.P., Levine, T.R., & Shaw, A.S. (2010). Content in context improves deception detection accuracy. Human Communication Research, 36, 423-442.
Moving Toward Ecology • Our thinking is strongly influenced by Brunswick and Gigerenzer • A Darwinian understanding of how psychological processes develop • Processes are adapted to environment • Both the process and the environment must be considered (2 blades of the scissors) • Procedure • Identify process(es) • Test environments to identify limits • Modify environments to assist the functioning of process • This is the direction that our research program is currently taking
Processes • Motive • Absent a motive for deception, deception judgments are not made • Levine, T. R., Kim, R. K., & Blair, J. P. (2010). (In)accuracy at detecting true and false confessions and denials: An initial test of a projected motive model of veracity judgments. Human Communication Research, 36, 81–101. • Demeanor • Tim has developed an 11 item demeanor scale • It predicts up to 82% of the variance in judgments • Still under review
Processes • Demeanor
Processes • Consistency • Coherence – consistency of a statement with itself or other’s statements • People adhere to this, but it doesn’t work very well • Granhag, P. A., & Stromwall, L. A. (2000). Deception detection: Examining the consistency heuristic. In C. M. Breur, M. M. Kommer, J. F. Nijboer & J. M. Reintjes (Eds.), New Trends in Criminal Investigation and Evidence II (pp. 309-321). Antwerpen: Intersentia. • Stromwall, L. A., Granhag, P. A., & Jonsson, A. (2003). Deception among pairs: "Let's say we had lunch and hope they will swallow it!". Psychology Crime & Law, 9, 109-124.
Processes • Consistency • Correspondence – consistency with external facts • Appears to operate in a linear fashion • As inconsistencies accumulate more deception judgments made
Processes • Consistency • Correspondence • Hartwig, M., Granhag, P. A., Stromwall, L. A., & Vrij, A. (2005). Detecting deception via strategic disclosure of evidence. Law and Human Behavior, 29, 469-484. • We also have a piece under review
Environments • We haven’t done much specific work in this area, but • Motive seems to be very general • Demeanor as well • Consistency (both coherence and correspondence) require extra information to utilize, but seem to be utilized when present • Only motive and correspondence seem to generally enhance deception detection accuracy • We are starting to work on how these processes operate in conjunction with each other
Modifying Environments • We consider the specific questioning utilized to be an environmental modification • We call this “Question Effects” • A question is effective when it causes a truth-teller to act like a truth-teller, a deceiver to act like a deceiver, or both • Acting like a truth-teller or a liar is defined based upon the previously discussed processes
Question Effects • Correspondence Example – Hartiwig’s (2005 &6) SUE. If the suspects are questioned in a way that gives away what the interviewer knows, the suspect makes his or her statement consistent with the information. Deception detection accuracy is reduced. • Coherence Example – Vrij’s et al.’s (2008) unexpected questions. Pairs of liars will practice their story and be more coherent than truth-tellers. Asking unexpected questions undoes this and makes coherence useful. • Demeanor Example – Levine & Blair’s (under review) question effects. Changed question from “why should I believe you” to “what will your partner say?” • Below chance accuracy with the first and above with the second
Test 2 The Facts: The victim is a Female, Hispanic, and 23 years old. The item stolen is a Black, JanSport backpack No weapon was used
The other ones Background information: The trivia test is extremely difficult. Most people who scored 3 or more probably cheated.
Expertise • A debate over expertise in detecting deception has gone on for some time • One camp has tested large numbers of people using distinct sets of videos to find a few “experts” (who score 80% or better on a subset of trials) • One camp has meta-analyzed the data and come to the conclusion that the is no evidence for expertise • Taking an ecological approach, we argue that there ought to be expertise, but that this expertise is situated within a particular environment • We are seeing if we can develop “experts” (without training) this summer
Summary • The dominant traditional approaches to deception detection research have produced modest results • Adopting an ecological approach seems to provide a flexible way forward • This approach considers the process in the environment • Three parts • Identification of processes • Testing of processes in environments to identify limits • Modification of environments to allow the processes to function effectively
Summary • Processes • Motive • Demeanor • Coherence • Correspondence • Environments • These processes should be available in most investigative contexts • They do not all function well in standard environments • Modification of environments • Question effects have been shown to impact the functioning of the processes in common environments • These effects can be good or bad