The BAI starts with the question “ What is your understanding of the aim of this interview ? ” followed by questions such as “ Did you commit the crime ? ” or “ Do you know who committed the crime ? ” or “ Who would have had the best opportunity to commit the crime if they had wanted to ? ” and “ Once we complete our entire investigation, what do you think the results will be with respect to your engagement in the crime ? ” Despite its name, behavior analysis interview, the BAI predicts that guilty and innocent suspects will differ in their nonverbal demeanor and besides in their verbal responses .
Regarding the nonverbal responses, it is assumed that liars feel more uncomfortable than accuracy tellers in patrol interviews. Guilty suspects should therefore show more skittish behaviors, such as crossing their legs, shifting about in their chairs, performing grooming behaviors, or looking away from the investigator while answering questions such as “ Did you commit the crime ? ” Regarding the verbal responses, it is assumed that compared with guilty suspects, impeccant suspects expect to be exonerated and consequently should be more incline to offer helpful information. thus, truth tellers should be less evasive in describing the purpose of the interview, more helpful in naming potential suspects when asked who they think may have committed the crime, and more likely to divulge who had an opportunity to commit the crime, and they should express more confidence in being exonerated when asked what they believe the result of the investigation will be.
Investigators who use the BAI protocol admit that not every response to a BAI doubt will systematically match the descriptions presented for guilty and innocent suspects. consequently, investigators should evaluate the responses to the integral BAI quite than to the 15 questions individually. There is lone one study with real-life suspects that used the BAI protocol successfully. When only conclusive decisions were scored, 91 % of the deceptive suspects and 80 % of the innocent suspects were classified correctly. Although these results appear impressive, the authors themselves noted an significant restriction of the analyze : They could not establish with certainty that the guilty suspects were sincerely guilty and the innocent suspects were truly innocent .
The BAI assumption that guilty suspects will feel less comfortable than truth tellers in a patrol interview is not universally accepted by the scientific community. For example, in situations where the consequences of being disbelieved are severe, both liars and truth tellers will be concerned about not being believed. The prediction that guilty suspects will show more anxious behaviors than innocent suspects is not supported by deception research. In a mock larceny testing ground study, where guilty and innocent suspects were interviewed via the BAI protocol, guilty suspects ( those who had taken the money ) did not differ from innocent suspects ( those who had not taken the money ) in center contact. With other behaviors, just the antonym of the BAI prediction occurred : guilty suspects displayed fewer movements than innocent suspects. A meta-analysis review more than 100 deception studies showed precisely the like practice : Eye contact is not related to magic trick, and liars tend to decrease rather than increase their movements. This radiation pattern was besides obtained in a real-world cogitation examining the nonverbal responses of suspects in police interviews. The decrease in movements much found in deception research could be the resultant role of liars ( guilty suspects ) having to think harder than accuracy tellers ( innocent suspects ). numerous aspects of lying lend to mental load. For model, liars must avoid making slips of the clapper, should not contradict themselves, and should refrain from providing possible leads. If people are engaged in cognitively demanding tasks, their overall animation is probably to decrease. An alternative explanation of liars ’ decrease movements is that liars typically experience a greater sense of awareness and slowness in their performance, because they take their credibility less for granted than do truth tellers. Although truth tellers are besides keen to be seen as truthful, they typically do not think that this will require any special feat or attention. As a result, liars are more inclined than truth tellers to refrain from exhibiting excessive movements that could be construed as nervous or fishy .
This latter impression management explanation ( liars put more attempt into making a convincing impression than accuracy tellers ) conflicts with the BAI ’ randomness prediction that guilty suspects will be less helpful than innocent suspects. The stamp management hypothesis states that guilty suspects will be keener than innocent suspects to create a golden impression on the detective, because liars will be less likely to take their credibility for granted. indeed, the results from the mock larceny lab study in which the BAI protocol was used showed good that pattern : guilty suspects were more helpful than innocent suspects .
References:
- Horvath, F., Jayne, B., & Buckley, J. (1994). Differentiation of truthful and deceptive criminal suspects in behavior analysis interviews. Journal of Forensic Sciences, 39, 793-807.
- Inbau, F. E., Reid, J. E., Buckley, J. P., & Jayne, B. C. (2001). Criminal interrogation and confessions (4th ed.). Gaithersburg, MD: Aspen.
- Vrij, A., Mann, S., & Fisher, R. (2006). An empirical test of the behavior analysis interview. Law and Human Behavior, 30, 329-345.
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