Interviewing to assess and manage threats of violence

Persons who pose threats of violence can be rich sources of information for professionals charged with ensuring safety and security. The interviewing of threateners is thus considered important among such professionals, but research on the topic is scarce. This thesis seeks to advance current knowledge by proposing a scientific perspective on effective threat assessment and management (TAM) interviewing. What are the expected dynamics when interacting with persons who threaten to cause harm and, given these dynamics, which interview methods work best? A novel experimental paradigm was developed and employed in Studies I, II, and III. Participants were given a fictitious case describing two conflicting parties and were then asked to take on the role of the threatening party in a subsequent interview with the conflicting party. 
Study I (N = 157) examined whether individuals’ intent to actualise a threat becomes evident in how they verbalise that threat. Intent was manipulated across three conditions through the likelihood to actualise the threat: low likelihood (no intent: bluffers), medium likelihood (weak intent: conditional actualisers), and high likelihood (strong intent: decisive actualisers). Based on theory and research in cognitive psychology, it was predicted that decisive actualisers would provide the most detail about the implementation of the threat, followed by conditional actualisers, and bluffers would provide the least. The opposite trend was found: Persons more likely to actualise a threat were found less informative about its implementation. 
Study II (N = 179) tested the effect of two interview techniques (low vs. high suspicion-oriented) on the information provided by bluffers and actualisers. Drawing on psychological research examining lie detection, it was theorised that the need to be believed would be more urgent for bluffers than for actualisers. Hence, bluffers were expected to be more forthcoming when questioned about their threats and, in particular, when the questions communicated suspicion. As expected, bluffers provided more information in response to specific questions as compared to actualisers, especially with regard to implementation details (replicating Study I). However, the difference between bluffers and actualisers was not further accentuated by the use of suspicion-oriented questions. Furthermore, Study II explored whether threatening participants had used counter-interview strategies. Participants were found to be forthcoming, while also being strategic and adaptive to interviewers’ responses. 
Study III (N = 120) tested the hypothesis that rapport-based interviewing would be more effective for threat assessment and management purposes than direct interviewing. Against expectations, no differences were found between interview protocols pertaining to the threateners’ use of counter-interview strategies, their information provision, or their willingness to pursue/discuss the threat. Furthermore, the study advanced Study II by exploring what types of counter-interview strategies threateners employ. Again, threateners were found to be both forthcoming and strategic. The most frequently reported strategies were to prove capability and to conceal information. 
Study IV was an online study that investigated whether threat assessments made by professionals were of higher quality than those made by non-professionals. Threat assessment professionals, university students, and laypersons assessed the risk for violence in three fictitious cases. In alignment with the literature on expert decision-making, it was predicted that professionals (vs. students and laypersons) would agree more with one another with respect to risk assessments, and that their information search would show more resemblance with empirically supported threat cues. The results supported both hypotheses. 
Taking the results of the studies together, it could be concluded that threateners are semi-cooperative interviewees, whose attitudes may not be impacted by general interview approaches (e.g. rapport-based, suspicion-oriented). Instead, the findings suggest that more strategic techniques developed from the perspective of threateners (which result in their motivation to be informative prevailing over their need to be strategic) are needed