The effects of cognitive load on investigative interviewer performance

Project code: PSYC3130217

Accurate and reliable witness testimony is essential to ensure fairness for all in the criminal justice system. Over the past thirty years, international psychological research has explored the encoding, retention and recall of information by witnesses. This research has informed forensic practice and guidance regarding best practice for the conduct of optimum investigative interviews. However, despite this advice, police officers do not, or perhaps cannot, comply with the guidance provided. This can have serious consequences for criminal justice, as poor interviews may be deemed inadmissible in court or may negatively impact upon the perceived credibility of witnesses. In the proposed project we explore some of the challenges faced by interviewers which may impair their performance and preclude them from following best practice guidelines.

During an interview there are numerous attentional demands that are imposed upon interviewers. For example, listening carefully to an interviewee, evaluating the information provided, deciding on which questions to ask, ensuring that optimum evidence is recorded and adhering to strict interview guidance. From a psychological perspective, interviewers have limited capacity to perform all of these difficult tasks.

The effort and attention required to conduct a complex interview is likely to result in fewer cognitive resources being available for other mental processes. As such, memory failure, susceptibility to bias and poor questioning may arise for interviewers. Furthermore, an interviewer’s ability to obtain ‘best evidence’ from a witness may be compromised if other attentional demands are present.
In sum, it is likely that cognitive load for interviewers is one of the reasons for their failure to comply with guidance. Investigative interviewers simply have too much to contend with. Previous research has explored the effects of cognitive load on interviewees although how it affects an interviewer in an applied setting has, to date, been overlooked. This programme of research has been designed to explore cognitive capacity limitations and their impact upon interviewers’ performance.