Law enforcement must be strategic in the questions they ask during interviews.

Law enforcement must be strategic in the questions they ask during interviews. Image source: Flickr user Stefan Baudy

“How was your day?” That’s a simple question, but would your answer be the same if I asked the question a different way?  “You seem frazzled. Did something happen today?”  Or, “What specifically happened today that upset you?”

How we formulate questions is just as important as the content, especially in a police interview where you have one chance to get it right. You don’t just jump in with the question meant to give the defining answer—in most cases, you first make the subject feel comfortable about opening up and then work up to the big question. Of course, if someone is standing there holding the smoking gun, it’s a different scenario than interviewing someone who has suffered trauma as a witness or victim.

There are different types of questions used in police interviews during the rapport-building phase, where you can be more casual in your conversational style. These questions are the foundation for a positive outcome—clearing a suspect or working towards a confession. Once you get down to the nitty-gritty, it’s all about focus, planning, and structure. After building a connection with the subject, the CVSA Examiner can administer Zone of Comparison (ZOC) or General Series. Both of these methods use control questions as a key element of the interview process, although some formats, such as Peak of Tension (POT), do not. Regardless, these are all standardized CVSA interview approaches which are vital in validating the truthfulness of a suspect’s answers.

Measuring Accurate Responses with the ZOC

As with any standardized test, there is a formula that needs to be followed—with allowances for modifications, of course, as each interview is unique. The ZOC method, which is the standard format for CVSA exams, uses nine questions. Out of these nine, two are control questions, two are relevant questions, and the rest are irrelevant questions.

CVSA Examiners start with a series of irrelevant questions such as, “Is today Monday?” as a baseline for measuring truthfulness. No one will get stressed out by such a question. Well, maybe Brenda Spencer, the teenager who went on a shooting rampage at her school in 1979 and claimed she didn’t like Mondays. That’s what we mean by each situation being unique and why you need to ask more than one irrelevant question.

Moving into relevant questions is when stress really starts to show in the suspect. These are questions directly related to the crime such as, “Did you take that money?” or less specific queries like, “Have you ever taken money that wasn’t yours in the past?”

A relevant question is similar to a control question, but the control question is designed to achieve a measurable response that truth verification technology can validate and can be historical in nature, such as asking about past activities. Although these questions are not directly related to the crime under investigation, they measure stress and provide a control, just as a scientific control does in a lab study. Control questions compare the individual’s responses to those of people who have given non-deceptive answers as a means of standardization for the examination.

The Peak of Tension Test

Control questions are a core element of the truth verification examination, but sometimes you need to ask more pointed questions known as the Peak of Tension Test (POT), another preferred method for CVSA Examiners. The format involves multiple-choice questions that can only be answered by someone with knowledge of the crime. For example, “Do you know if $10, $100, or $1000 is missing?” and then follow up with “Is $10 missing?”

This line of questioning helps gain more specifics and measure deception on a truth verification examination, but not every guilty person knows all the answers. For example, if you ask a suspect if there were drugs in the house, he might say, “yes.” Asking if the drugs were in the kitchen might also elicit a “yes”; asking if they were hidden in a cereal box, “yes, they were.” What brand of cereal was it? Well, he might not remember that. Law enforcement should carefully consider how to use these details when formulating POT or similar questions built around guilty knowledge.

Although interviewing suspects and administering a truth verification examination is a fluid process, investigators need to maintain control over the situation. Think of it like a body of water that is constantly moving but is restricted by a dam or a levee. A flood of information is only positive when the investigator is the one who regulates the flow, and using reliable standardized questioning techniques enables officers to do so.

Please reach out to us at NITV Federal Services to learn more about our CVSA systems and training programs.