Preparing an Investigative Interview

May 31, 2021

A couple of years ago, I went downtown to see the musical “Les Miserables”. Although it was touted as an incredibly cultural event that would make me a better person, all I got from it was that pre-revolution France sure had a lot of extremely loud citizens, many of whom were dirty and owned at least one pitchfork. 

I readily admit that my lack of appreciation was more due to my musical taste (or lack thereof), but I was only able to stay in my seat until the intermission by distracting myself. I paid attention to everything except the throng of unwashed yellers, and I was far from bored. 

There was so much going on in the background that I could have kept myself amused for days. I activated my selective attention and noticed aspects of the production that I probably wouldn’t have picked up on had I appreciated the music and acting; aspects that were as important to the end result as the singing, dancing and yelling. The costumes, the make-up, the set design, the acoustics, the lighting, and the audio-visual equipment were exquisitely prepared, and played a huge role in the success of the production. On the way home, it struck me that we often undervalue what goes on in the background and focus primarily on the “main event”. 

Understanding goals and agendas is often integral to conducting an efficient interview.

As a police interviewer, I recognized that the planning and preparation of an interview, as with a stage production, could have a profound effect on the end result. With interviewing, it could be a deciding factor in the quantity and quality of information received. 

Let’s look at some factors that should be considered when planning to interview an adult – whether a witness, victim or suspect. This is not an exhaustive list and, as with many facets of interviewing, it is not cast in stone. They are to be applied according to the context and circumstances unique to each situation.

While the word “agenda” may have various definitions in relation to investigative interviewing, I prefer to think of it as the information a person, either witness or suspect, chooses to mention or omit during the interview. This agenda may differ between witnesses for many reasons, some of which may be purely idiosyncratic. Regardless, it is what they are willing to mention in a free-recall narrative and, therefore, might be open to being questioned on further into the interview process. 

Generally, a witness or victim will have an agenda similar to the interviewer’s. Both parties share a desire to provide the investigation with complete and reliable information. A suspect, on the other hand, due to potential jeopardy associated with providing truthful information, may have an agenda that differs from the interviewer’s. This term, whether used in relation to a witness or a suspect, might dictate the route the interview should take if the goals are to be reached. 

In general, the suggestion is to exhaust the interviewee’s agenda before moving on to the interviewer’s agenda. This general rule allows for a more conversational tone and could motivate the interviewee to provide fine-grain detail in a non-threatening, conflict-free manner. 

Moving to the interviewer agenda prematurely could have the deleterious effect of shutting the interviewee down before s/he had provided all the information that would have otherwise been provided.

Goals of a witness interview

The primary goal of an investigative interview is to obtain information that is both complete and reliable. This means that a Cognitive Interview framework should be used as the environment in which the interview would take place would be consistent with what we know about human memory and recall. More specifically, the interview should be conducted in an atmosphere conducive to achieving the goals of completeness and accuracy. Whereas some may argue that an appropriate framework should also ensure a credible account, this is often misleading. Reliability and accuracy are related to the content provided (the words uttered by the interviewee), however, credibility holds a closer link to the attitude or agenda of the interviewee. 

The reason these terms must be differentiated is that there may be times that an interviewee might be credible, he or she has chosen to provide accurate and complete information; however, due to one of many possible factors, is unable to achieve the qualitative or quantitative goals of the interview. (R. v. Mitchell (ONSC) [November 13, 2018]), (R. v. H.C., 2009 ONCA 56)

An additional goal of any interview is to commit the interviewee to a version of events so that their version could not evolve with time to either intentionally mislead or because of some frailty associated to human memory. When recording equipment is used (which should always be a best practice), the history of a person’s account could be tracked and assessed as the investigative process unfolds. Even if a witness says they don’t remember what happened, the mere fact that this has been caught on audio will allow a prosecutor to prepare for trial knowing what each witness would or would not be able to say. It would also help the prosecutor deal with a hostile or adverse witness by being able to prove to the Courts that a prior inconsistent statement had been given.

Goals of a suspect interview

The witness goals would still apply, complete and reliable information, but there would be more emphasis on aspects related to Court admissibility and adherence to ethical standards. Moreover, it could be argued that the aspect of credibility could present more often in a suspect interview due to an increased desire on the part of some suspects to present an agenda that differed from the interviewer’s. What this means is that, generally, a witness would present in a more neutral manner and provide information based more on memory than a guarded or protective agenda. The witness’ agenda would be to tell the truth as s/he believed it. Conversely, a suspect, who had reason to hide from detection, might modify his or her account to suit a pre-determined agenda.

Examples of this agenda are:

  • Telling the complete truth.
  • Complete denial … “I didn’t do it.”
  • Partial truth … “I was there, but was only a witness.”
  • An alibi … “I wasn’t even there. I was on the other side of town at that time.”
  • Technical denial … “I did not hit her with my fist.”
  • Providing an objection … “I am not a violent person.”
  • Rationalization by minimizing the moral gravity … “This was the only time.”
  • Rationalization by projecting all or an aspect of blame on someone or something else … “She started it.”

In presenting the potential agenda differences between a witness and suspect, I am in no way suggesting that all witnesses have a saintly agenda, or that all suspects aim to mislead in some way. Nor am I suggesting that considering the interviewee agenda before and during an interview would relieve us of implicit and confirmation bias. 

What I do hope to achieve by raising this point is simply to ensure interviewers consider the potential of an interviewee agenda that conflicts with their own and that he or she hold firm to a framework that reduces the likelihood that any resultant biases would leak into the interview process. In short, suspect interviews are often inherently different than witness interviews so a one-size-fits-all approach would not be recommended. 

Bruce Pitt-Payne would like to acknowledge those whose work has greatly influenced his writing: Dr. Andy Griffiths, Dr. Eric Shepherd, Dr. John Yuille and Dr. Hugues Herve.