Interviewing Suspects Strategically: Factors to Consider when Gathering and Disclosing Information in Interviews with Suspects

Disclosing police information to suspects is a key factor in receiving relevant information during investigative interviews. However, such disclosure must be done with skill: because an innocent suspect may be overwhelmed and may confess falsely or a guilty suspect may manoeuvre around the evidence. In order to (a) minimise such risks, (b) support police interviewers in their work, and (c) amplify potential differences between guilty and innocent suspects, several models of ‘strategic interviewing’ have recently been developed.

The current work offers an original contribution to the literature and the field by further conceptualising the underlying mechanisms that are at play in these strategic interviewing models, by discussing extensively one of these models, and by proposing a way to measure their effects based upon a taxonomy of real suspect interview behaviour. The results of the first empirical study in this work (with 53 interviewers having conducted 100 mock interviews) demonstrate that, with several important naturalistic conditions taken into account, all three of the tested models enable interviewers to collect further information in the probing and challenging phase of the interview; and they sometimes also lead to suspects shifting from denying the crime to admitting to it. Both models that instruct interviewers to challenge suspects by disclosing police information in a gradual manner appear to have a potential slight benefit compared to the third, ‘late approach’ model. The second study (with 29 interviewers having conducted 37 mock interviews) found that these models can easily be combined with a precursory free account phase. Although relatively little information is collected on average in this free account phase, it may be very relevant information, such as confessions or suspects admitting that they have been at the crime scene.

The third and fourth empirical studies focused on the awareness of interviewers and senior investigative officers that within strategic interviewing the police may unwittingly disclose incorrect information to suspects; and on their adaptiveness to handle such a situation when being confronted with it. In a sample of fifty interviewers, four interviewers turned out to be maladaptive in this regard, 35 were neutral in their stance, and eleven responded adaptively. Their stance furthermore tended to have positive associations with expertise (training), and correlated negatively with experience (years of service). Also, about seventy per cent of a sample of 115 senior investigating officers was adaptive in this xiv regard, but significantly more so if the interviewer had been neutral or adaptive, not maladaptive.

Overall, the data and findings offer support for the use of strategic interviewing models in the probing and challenging phase of interviews with suspects. They are not only internally valid and considered ethical, but this work found that they remain effective under more naturalistic conditions. Having a strategy seems in this regard more important than having a specific strategy. The potential risks following from the chance that interviewers’ strategic disclosure of information may include incorrect information can be mitigated by the awareness both interviewers and senior investigative officers have about this phenomenon.