Information is the lifeblood of investigations and it is the ability of investigators to obtain useful and accurate information from witnesses that is most crucial. Yet full and accurate memory recall is difficult to achieve. The Cognitive Interview (CI) technique developed by Geiselman and Fisher is a systematic approach to interviewing witnesses toward increasing the amount of relevant information obtained without compromising the rate of accuracy. The CI is based on scientifically derived principles of memory and communication theory as well as extensive analyses of law-enforcement interviews. The CI has been found in scientific studies to produce significantly more information than standard police questioning.
The CI as an information-gathering technique has been tested in approximately 100 laboratory tests, most of which were conducted in the United States, England, Germany or Australia. In these studies, volunteer witnesses (usually college students) observed either a live, innocuous event or a videotape of a simulated crime. Shortly thereafter (ranging from a few hours to several days), the witnesses were interviewed by a trained researcher—or in some cases by experienced police officers—who conducted either a CI or a control interview. The control interview was either modeled after a typical police interview or after a generally accepted interview protocol, e.g., the Memorandum of Good Practice (1992). Across these studies, the CI typically elicited between 25 % – 40% more correct statements than did the control interview. The effect is extremely reliable: Of the 55 experiments examined in a meta-analysis conducted in 1999, 53 experiments found that the CI elicited more information than did the comparison interview (median increase = 34%). Equally important, accuracy was as high or slightly higher in the CI interviews than in the comparison interviews.
The CI has been taught and adopted by several policing agencies and allied investigative agencies worldwide. Those agencies include: FBI, NTSB, Department of Homeland Security, Defense Intelligence Agency, UK Home Office, Calgary Police Service, Singapore Police Force, ICAC (Hong Kong), as well as several mid-level police departments around the United States.
More recently, research on investigative interviewing in my laboratory has focused on potential suspects. This work was designed to examine a select group of indicators of deception and truthfulness from the existing literature toward identifying a more reliable and manageable subset of such indicators. Participants were asked to generate narrative accounts of true autobiographical events and narrative accounts of confabulated autobiographical events. Immediately before generating these stories, each participant was informed of a reverse chronological order requirement taken from the basic CI protocol. This was to increase the cognitive load on the story teller. The contents of the tape-recorded stories told in reverse order were examined for select verbal and vocal indicators of deception and truthfulness. The results suggested that confabulated oral reports most often are limited in contextual details and interactions, and contain spontaneous justifications for what is said. These bare-bones reports often are spoken in sentence fragments with frequent stops and starts at an uneven rate of speech. As a practical application, McCormack, Geiselman, et al. reasoned that first responders might be able to rely on this limited set of indicators, in addition to behavioral cues, to assess the likelihood of deception in conversations with persons who have already raised suspicion.
Therefore, a set of experiments was designed to refine the limited, manageable set of verbal, vocal, and behavioral indicators to discriminate truthful from deceptive oral narratives and exchanges, and then to evaluate the ability of laypersons to accurately judge the veracity of oral statements both before and after training. The results of the training experiments demonstrated that laypersons without training do not discriminate prototypical truthful and deceptive exchanges very well, but instead exhibit a significant bias toward labeling an exchange as deceptive even when the exchange contains the more reliable signs of truth. The results further demonstrated that laypersons with limited training do not discriminate actual truthful and deceptive narratives and exchanges very well either, and they also appear to focus on indicators of deception rather than truthfulness. These findings are consistent with data from some past studies with laypersons and illustrate that insufficient training can lead to more errors and inflated confidence in the errors compared with no training at all.
Our research on training law enforcement officers to detect deception has shown that plenty of practice with video clips and feedback is necessary to improve the accuracy of their judgments reliably. The same is likely to be true with laypersons. Otherwise, more limited exposure to the training guidelines can produce an outcome that is less accurate than before the training. In contrast, with extensive experience in detecting deception, both police detectives and Marine Intelligence officers can detect deception with high accuracy. Therefore, current research is exploring more substantial protocols for training to detect deception. In particular, the training must emphasize skills for relying on multiple indicators and for weighing indicators of truthfulness as well as deception. This research is underway at the present time to evaluate a 4-day, 12-hour training program toward improving laypersons’ skills for detecting deception. This work is being conducted jointly with faculty at Hong Kong University.
For further readings on this research, please see:
Fisher, R. P. & Geiselman, R. E. (1992). Memory-enhancing techniques in investigative interviewing: The cognitive interview. Springfield, IL: C.C. Thomas.
Geiselman, R.E., Elmgren, S., Green, C., & Rystad, I. Training laypersons to detect deception in oral narratives and exchanges. American Journal of Forensic Psychology, 32, 1-22 (2011)
Geiselman, R.E. & Fisher, R.P. (1997). Ten years of cognitive interviewing. In D. Payne & F. Conrad (Eds.) Intersections in basic and applied memory research. New York: Lawrence Earlbaum (pp 291-310).
Geiselman, R.E., Saywitz, K.J., & Bornstein, G.K. (1993). Effects of cognitive questioning
techniques on children’s recall performance. In G. Goodman and B. Bottoms (Eds.), Understanding and improving children’s testimony: Developmental, clinical, and legal issues. New York: Guilford Publ. (pp. 71-94).
McCormack, T., Ashkar, A., Hunt, A., Chang, E., Silberkleit, G., & Geiselman, R.E. (2009). Indicators of deception in an oral narrative: Which are more reliable? American Journal of Forensic Psychiatry, 30, 49-56.