Police Strategies and Suspect Responses in Real-Life Serious Crime Interviews

This research focuses exclusively on real-life taped interviews with serious crime suspects and examines the strategies used and types of questions asked by police, and suspects’ responses to these. The information source was audio-tape-recorded interviews with 56 suspects. These recordings were obtained from 11 police services across England and Wales and were analysed using a specially designed coding frame. It was found that interviewers employed a range of strategies with presentation of evidence and challenge the most frequently observed. Closed questions were by far the most frequently used, and open questions, although less frequent, were found to occur more during the opening phases of the interviews. The frequency of ineffective question types (e.g. negative, repetitive, multiple) was low. A number of significant associations were observed between interviewer strategies and suspect responses. Rapport/empathy and open-type questions were associated with an increased likelihood of suspects admitting the offence whilst describing trauma, and negative questions were associated with a decreased likelihood

Heart rate variability (HRV) and muscular system activity (EMG) in cases of crash threat during simulated driving of a passenger car

Objectives: The aim of the study was to verify whether simultaneous responses from the muscular and circulatory system occur in the driver's body under simulated conditions of a crash threat. Materials and Methods: The study was carried out in a passenger car driving simulator. The crash was included in the driving test scenario developed in an urban setting. In the group of 22 young male subjects, two physiological signals - ECG and EMG were continuously recorded. The length of the RR interval in the ECG signal was assessed. A HRV analysis was performed in the time and frequency domains for 1-minute record segments at rest (seated position), during undisturbed driving as well as during and several minutes after the crash. For the left and right side muscles: m. trapezius (TR) and m. flexor digitorum superficialis (FDS), the EMG signal amplitude was determined. The percentage of maximal voluntary contraction (MVC) was compared during driving and during the crash. Results: As for the ECG signal, it was found that in most of the drivers changes occurred in the parameter values reflecting HRV in the time domain. Significant changes were noted in the mean length of RR intervals (mRR). As for the EMG signal, the changes in the amplitude concerned the signal recorded from the FDS muscle. The changes in ECG and EMG were simultaneous in half of the cases. Conclusion: Such parameters as mRR (ECG signal) and FDS-L amplitude (EMG signal) were the responses to accident risk. Under simulated conditions, responses from the circulatory and musculoskeletal systems are not always simultaneous. The results indicate that a more complete driver's response to a crash in road traffic is obtained based on parallel recording of two physiological signals (ECG and EMG)

Where bias begins: a snapshot of police officers’ beliefs about factors that influence the investigative interview with suspects

The aim of the current study was to obtain a snapshot of police officer’s beliefs about factors that may influence the outcome of the investigative interview with suspects. We created a 26-item survey that contained statements around three specific themes: best interview practices, confessions and interviewee vulnerabilities. Police officers (N = 101) reported their beliefs on each topic by indicating the level of agreement or disagreement with each statement. The findings indicated that this sample of officers held beliefs that were mostly consistent with the literature. However, many officers also responded in the mid-range (neither agree nor disagree) which may indicate they are open to developing literature-consistent beliefs of the topics. Understanding what officers believe about factors within the investigative interview may have implications for future training. It may also help explain why some officers do not consistently apply best practices (i.e. strong counterfactual beliefs) versus officers who reliably apply literature-consistent practices to their interviews (i.e. knowledge-consistent beliefs).This research is supported by a fellowship awarded from the Erasmus Mundus Joint Doctorate Program, The House of Legal Psychology (EMJD-LP) with Framework Partnership Agreement (FPA) 2013-0036 and Specific Grant Agreement (SGA) 2015-1610 awarded to Nicole Adams.Published onlin

Homicide of Strangers during Psychotic Illness

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