A vital aspect of working as an investigator is skill as an interviewer. Numerous systems and methods exist for interviewing suspects and witnesses, as well as various types of interview training. For new or experienced interviewers looking to improve their skills, the options may seem overwhelming. When looking for an interviewing style or method to suit one’s skills, it makes sense to learn the differences between them, strengths and weaknesses of each, and latest related science.

1. Preparation and planning
2. Engage and explain
3. Account clarification and challenge
4. Closure
5. Evaluation

The PEACE model focuses on determining relevant facts, as opposed to seeking confessions. With this technique, “interviewers are encouraged to be fair and open-minded and to pursue reliable, true and accurate information.”⁶

While there certainly are similarities between the PEACE and Reid methods, especially the interviewing phase of the Reid technique, distinct differences exist in the way interviewers approach subjects. In interviews reflecting the PEACE model:

The investigators frequently asked open-ended, leading, and repetitive questions; disclosed evidence to suspects; and challenged suspect’s accounts, often by pointing out contradictions and inconsistencies. Yet, they never resorted to threats, promises and intimidation, or the kinds of maximization and minimization tactics through which threats and promises are often implied.⁷

To date, the PEACE technique has proven as successful as the Reid at obtaining confessions from the guilty.⁸

Cognitive Approach

The Cognitive Interview technique also shares similarities with the PEACE model. This method hinges on three psychological processes: 1) memory and cognition, 2) social dynamics, and 3) communication. The Cognitive method attempts to guide interviewees through their memories to obtain the richest and most relevant information possible. This usually is accomplished by using cognitive resources efficiently and asking open-ended questions followed by more specific probing inquiries. In this technique, there are separate approaches for witnesses and suspects.⁹

For witnesses, the Cognitive approach involves five steps.

1. Introduction
2. Open-ended narration
3. Follow-up questions
4. Review
5. Closing

In this model, subjects are “encouraged to generate large amounts of information before any challenge is made.”¹⁰ In effect, the Cognitive technique allows interviewees to provide the details they deem important to their experience. The interviewer’s purpose in the process is “to guide the witness to those memory records that are richest in relevant information and to facilitate communication when these mental records have been activated.”¹¹

This technique does not rely on confrontation, but rather on the interviewer helping the witness revisit the scene and recall as much as possible. Interviewees should do approximately 80 percent of the talking. This distribution can be accomplished by an interviewer who relies on open-ended questions and careful guidance to assist the interviewee in invoking the external (e.g., weather, room details), emotional (e.g., fear, mood) and cognitive (e.g., thoughts) factors around the event.¹²

When interviewing a suspect, the Cognitive model differs in that it includes eight steps.

1. Introduction
2. Narrative
3. Drawing/sketch
4. Follow-up with open-ended questions
5. Reverse-order technique
6. Challenge
7. Review
8. Close¹³

Much like the PEACE method and the interviewing stage of the Reid system, the Cognitive technique is generally nonconfrontational. However, there are built-in mechanisms designed to increase the cognitive load on the brain.

One example of this is the reverse-order technique, wherein interviewees must tell their stories backwards. Research reveals that the reverse-order process is particularly difficult for people with fabricated stories.¹⁴ This is because people are used to telling stories chronologically. Changing the order requires more thinking and processing, causing liars to make mistakes in their narratives, which collected evidence and witness testimony can disprove.

Kinesic Method

The Kinesic Interview Technique is like the Cognitive method in that it relies on moving the mind and body out of equilibrium and on the human reaction to stress. Advocates of the technique believe that this reaction, prompted by questioning, will lead to meaningful behaviors exhibited by verbal and nonverbal indicators of deception.¹⁵

The Kinesic method identifies three distinct categories into which meaningful behavior can be divided.

1. Self-initiated statements by suspects, which they make without prompting
2. Prompted verbal responses after interviewers ask certain questions
3. Nonverbal body positioning—physiological changes and gestures or lack thereof ¹⁶

After establishing baseline behaviors for the interviewee, investigators watch and listen for deviations from the norm.

Strengths and Weaknesses

In recent years, the number of studies done on each of these techniques has increased, with intriguing findings. Scientists have found positives in the Reid technique, which, “among others, can be effective in eliciting true confessions largely as a result of social influence processes that have been shown to produce powerful effects in psychological studies of conformity, obedience to authority, and compliance to requests.”¹⁷

However, these same social influence processes also can have a negative effect in the form of false confessions, particularly when “the techniques of interrogation which rely on pressure and persuasion, sometimes coercion, steadily break down a suspect and change their perceptions of their situation such that they come to see the act of confessing as being in their self-interest or the only way to get out of a situation.”¹⁸

Although most Reid technique-trained investigators do not wish to extract a false confession, they sometimes are unaware of the psychological impact of their approach, as well as their own potential biases.

There are three sequential errors, which occur during a police-solicited false confession, that lead to a wrongful conviction. Investigators first misclassify an innocent person as guilty; they next subject him to a guilt-presumptive, accusatory interrogation that invariably lies about evidence and often involves the repeated use of implicit and explicit promises and threats as well. Once they have elicited a false admission, they pressure the suspect to provide a postadmission narrative that they jointly shape, often supplying the innocent suspect with the (public and nonpublic) facts of the crime.¹⁹

The Reid and Kinesic techniques rely on the interpretation of verbal and nonverbal behaviors classified as deceptive, but science has shown that humans are not good at interpreting such signals. Research actually indicates that people are better at detecting deception when they listen only to the audio of a statement, instead of both watching and listening.²⁰ In general, individuals “have little more than coin-flipping odds of guessing if someone is telling the truth, and numerous surveys have shown that police do no better.”²¹

In one study, the only difference in the detection of deception between random people on the street and trained law enforcement officers was the confidence in their ability to do so. Students actually outperformed police officers, but the officers were more certain they were correct.²²

Implicit and explicit biases also come into play with each of the interview techniques described. As investigators listen to and assess interviewees, they may not take into account their own preformed opinions concerning guilt or innocence. This internal bias can be a fatal problem for each interview technique:

A volume of research has demonstrated that when a person generates a specific hypothesis early in an investigation (e.g. this person is guilty), their attention becomes focused on information that confirms their hypothesis (e.g. evidence that suggests the person is guilty), while information that contradicts their hypothesis (e.g. exculpatory evidence) tends to be ignored or overlooked.²³

The Cognitive and PEACE techniques have their own unique sets of strengths and weaknesses, in addition to the issues described previously. Early studies of the PEACE model have shown promise, revealing a significantly lower rate of false confessions. Still, considering the fact that most of the relevant research is from the United Kingdom, there remains some question as to how much culture plays a role in the success.²⁴

Meanwhile, studies have shown that the Cognitive system provides more valid details than other methods while maintaining accuracy. This approach also can assist individuals in recalling complex events and enhance episodic memory. Investigators were able to elicit 55 percent more information from a subject after receiving Cognitive technique training.²⁵

Weaknesses of the Cognitive method include the time it takes to administer the interview, the focus needed by the interviewer to administer the technique successfully, and the fact that it does not work as effectively on certain segments of the population.²⁶

Importance of Silence

The future of interviewing, regardless of technique, may be best advanced if interviewers allow their subjects to do more of the talking.

One afternoon in January 2012, a man’s head and other severed body parts were found in Los Angeles, California. Police identified a suspect, but because they had nothing but circumstantial evidence, they needed a confession to charge him. However, despite consenting to three different interviews, he revealed nothing of substance.²⁷

In March 2014, detectives arranged for another interview of the suspect, who since had established a new life in Texas. He told the interviewing officers that he only had half an hour to talk before he had to return to his job. The detectives agreed and told the man that they wanted to hear his side of the story. They did not interrupt his narration or ask many questions.

What happened next completely surprised them. The suspect spoke with the two interviewers for almost 5 hours. During this time, he called his work to say he was sick and his wife to tell her that he would be home late. In the interview, the man revealed details that later would lead to information needed to obtain an arrest warrant and a conviction. “It was the strangest thing. He should have been on his guard. But, the less police talked, the more he did.”²⁸

Conclusion

There are proponents for any kind of interviewing method, but an interviewer who knows the strengths, weaknesses, and science behind each technique is better prepared to obtain the truth. Each of the techniques described can be effective in a given situation, and investigators must decide which of these methods best suits their personal style, as well as what combination of tactics fits the needs of their suspects and witnesses. They also must remember that all interviewers seek the truth, but if they are doing most of the talking, even the best technique will not get them the information they need.