Expect the Unexpected? Variations in Question Type Elicit Cues to Deception in Joint Interviewer Contexts DOMINIC J. SHAW 1 *, ALDERT VRIJ 1 , SHARON LEAL 1 , SAMANTHA MANN 1 , JACKIE HILLMAN 1 , PÄR ANDERS GRANHAG 2 and RONALD P. FISHER 3 1 Psychology Department, University of Portsmouth, UK 2 Psychology Department, University of Gothenburg, Sweden 3 Psychology Department, Florida International University, US Summary: We examined the effect of (i) a second interviewer’s demeanour and (ii) asking expected and unexpected questions on cues to deception. We predicted that liars compared with truth tellers would provide more detail to expected questions and less detail to unexpected questions, particularly when the second interviewer is supportive. Liars prepare answers for expected questions, and a supportive interviewer will encourage them to provide more detail. By definition, liars have not prepared answers for unexpected questions, and their answers to such questions will be less detailed. Participants (N = 168) appeared before two interviewers: The first asked all the questions, and the second remained silent. The second interviewer exhibited either a supportive or a neutral demeanour. As predicted, liars provided more detail to expected questions and less detail to unexpected questions, particularly when the second interviewer was supportive. In conclusion, a supportive second interviewer elicits cues to deceit. Copyright © 2013 John Wiley & Sons, Ltd. Suspects are frequently interviewed with two interviewers present in the room. For example, a survey amongst UK police officers revealed that 68% of interviews with juvenile suspects are conducted with more than one investigator present (Sim & Lamb, 2012). In addition, suspect interviews in human intelligence settings are also frequently carried out with two interviewers (Soufan, 2011). Research papers on using pairs of interviewers, outside the intelligence (or police) context, have revealed three advantages of this technique (Huber & Power, 1985; Kincaid & Bright, 1957). First, it is efficient as one interviewer can engage in conversation while the other can concentrate on recording answers accurately and completely. Second, when the interview becomes unstruc- tured or when the first interviewer vigorously pursues one train of thought, a second interviewer can pick up on points missed by the first interviewer. Third, when analysing the interviews, the second interviewer can aid the recall of the first. Despite the frequent use of two interviewers, there is not much forensic research examining the effect of using a second interviewer on suspect’s responses. In the present experiment, we exam- ined which demeanour (being supportive or neutral) a second interviewer should adopt to maximise verbal differences between truthful and deceptive interviewees. We examined the effect of the second interviewer’s demeanour on the answers to (i) questions that were in all likelihood anticipated and (ii) questions that were in all likelihood not anticipated. THE EFFECT OF THE SECOND INTERVIEWER Mann et al. (in press) are to our knowledge the only researchers to date to have examined the effect of a second interviewer on the verbal recall of truth tellers and liars. They found that truth tellers were more detailed than liars, partic- ularly when the second interviewer displayed a supportive demeanour (head nodding, smiling and an open posture). A supportive interviewer facilitates talking and encourages cooperative witnesses (e.g. truth tellers) to talk (Bull, 2010; Fisher, 2010; Memon, Meissner, & Fraser, 2010; Milne & Bull, 1999). For example, an experiment examining the effect of rapport on eyewitness recall of a dramatic videotaped event showed that participants in the ‘rapport’ interviewer-attitude condition recalled more correct, and the same amount of incorrect, information as participants in the ‘neutral’ and ‘abrupt’ conditions (Collins, Lincoln, & Frank, 2002). Talkative truth tellers raise the standard for liars, who also need to become more talkative to match truth tellers. Liars will not always be able or willing to do this. Liars may be unable to because they lack fantasy to fabricate additional de- tail (Köhnken, 1996; 2004), or they may be unwilling because they fear that the additional detail sounds implausible or that it increases the opportunity for interviewers to verify these details and discover that they are lying (Hartwig, Granhag, & Strömwall, 2007; Masip & Ces, 2011; Nahari, Vrij, & Fisher, 2012a, 2012b). In sum, a supportive second interviewer makes truth tellers, but not liars, more willing to talk, resulting in enhanced differences in the amount of detail truth tellers and liars provide when a second interviewer is present. The questions used by Mann et al. (in press) originated from a previous study (Warmelink, Vrij, Mann, Leal, & Poletiek, 2011, published online), and were rated as unexpected by the participants. Unexpected questions require liars to provide unprepared, spontaneous answers. Spontaneous lies contain fewer details than spontaneous truthful stories (DePaulo, Lindsay, Malone, Muhlenbruck, Charlton, & Cooper, 2003; Masip, Sporer, Garrido, & Herrero, 2005; Sporer, 2004; Vrij, 2005; 2008), and as Mann et al. (in press) found, a supportive second interviewer enhances this difference between truth tellers and liars. The opposite effect, that liars provide more detail than truth tellers which is further enhanced by a support- ive second interviewer, may occur when liars expect the questions and prepare answers to them. Observers pay attention to detail, and the richer an account is perceived to be, the more *Correspondence to: Dominic Shaw, University of Portsmouth, Psychology Department, King Henry Building, King Henry 1 Street, Portsmouth, PO1 2DY, UK. E-mail: dom.shaw@port.ac.uk Copyright © 2013 John Wiley & Sons, Ltd. Applied Cognitive Psychology, Appl. Cognit. Psychol. 27: 336–343 (2013) Published online 25 February 2013 in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/acp.2911