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Workplace Investigations

Mining for Details from the Eyewitness: The Latest Research in Cognitive Interviewing & Practical Tips

Interviewing Witness
© Marcel De Grijs | Dreamstime

One of the key challenges of a workplace investigator is to determine who did what and when – a challenge that becomes much more arduous when eyewitnesses fail to recall important details. In RT’s workplace investigation training course, Assessing Credibility, we teach participants about different interviewing strategies to enhance an interviewee’s memory.

New Approaches to Cognitive Interviewing

Elizabeth Fontaine, a PhD candidate at the University of Adelaide, Australia, recently produced a thesis that examines ways to enhance the “cognitive interviewing” technique. While Fontaine’s study is preliminary, it highlights two helpful tactics for conducting interviews in situations where an interviewee’s ability to recall key information is essential, or even merely helpful, in determining the outcome of an investigation.

Cognitive interviewing is an interview method created by psychologists to enhance the quantity and accuracy of eyewitness testimony. This is achieved by posing questions that mimic the way in which the human brain retains memories of past events. Since it was first introduced in the 1980s, it has been tested across various types of investigations and cultural contexts, and many scholars have critiqued the various tools that comprise this interviewing method and added additional tools based on further experiments.

In Fontaine’s thesis she explains the four main elements – or “retrieval mnemonics” – that comprise the cognitive interviewing technique:

  1. Mental Reinstatement of Context – an interviewee is either taken to the scene of a particular event or is asked to remember all aspects of the scene (time of day, smell, level of light, etc.) and the interviewee’s personal context at that time (what they were doing, how they were feeling, etc.).
  2. Report Everything – an interviewee is encouraged to discuss all aspects of a particular event, regardless of how trivial they may be.
  3. Change Order – an interviewee is asked to reframe their memory in a different time sequence, such as starting from the most recent event and going back to the oldest event.
  4. Change Perspective – an interviewee is encouraged to re-examine an event from the perspective of another individual, such as a bystander.

In Fontaine’s study she assessed how additional instructions could improve the quality and accuracy of information evinced from interviewees. These instructions included:

  • The Naivety Instruction – an interviewer tells the interviewee that because the interviewer was not present for the events in question, they have no conception of what happened. Psychologically, this places the interviewee in a position whereby they control the flow of information, and encourages them to divulge as much as possible. In the context of Fontaine’s study, in which subjects were asked to inform the interviewer of what they had seen in a film, the interviewer expressed the naivety instruction in the following way:

“I have not seen it [the film] myself, so I do not know what you witnessed. You have all the Information and I’d like you to share it with me.”

  • The Report-Detail Instruction – an interviewer tells the interviewee to describe everything they report in detail. In Fontaine’s study, they were simply told to “recall as many details as possible.” This is similar to the Report Everything component of cognitive interviewing, but is intended to encourage the interviewee to provide a more finely detailed account. For example, instead of saying that an individual was wearing dark clothing, the interviewee may recall that the individual wore a navy t-shirt and black jeans.

Fontaine’s study found that using both of these instructions had the following effects on interviewee’s reports:

  • An increase in correct information
  • An increase in more finely detailed information
  • An increase in central, as opposed to peripheral, information

Each interviewer will have a set of tools that reflect their personal style. But seeing how certain methods fare in a rigorous study like Fontaine’s offers interviewers an opportunity to reflect on their practices and experiment with new ones.

Key Takeaways

If you are involved in an investigation where the details of the eyewitness are instrumental to your fact-finding mission, consider including these three instructions in the preamble to your interview to incorporate elements of the cognitive interviewing technique:

  1. “I want to take you back to this specific moment in time. It’s important that you try your best to picture that day as clearly as possible. For example, can you think about how you were feeling that day, perhaps what you were wearing and how you went about your day?”
  2. “I want you to give me as much detail as possible when you tell me what happened. Don’t worry if the detail seems insignificant to you. Reporting on every aspect of your memory of this moment will be extremely helpful to me.”
  3. “I want you to remember that I have no preconceived notions about this. I have no idea what happened in that moment. I am here talking to you because you are the source of all the knowledge I will have about this.”

William Goldbloom


About the Author: William Goldbloom develops and delivers training sessions that educate clients about their legal obligations in the workplace. William also conducts workplace assessments and investigations to help employers prevent, address and resolve issues related to discrimination, physical, verbal and psychological harassment, violence, poisoned environments and bullying.