4. Factors influencing detection accuracy
- Investigation Guides
- An Employer's Guide to Conducting Internal Investigations
- 47 Quick Tips: Better Investigation Interviews
- Checklist for Sexual Harassment Investigations
- Black Book of Lie Detection
“A half-truth is a whole lie” – Yiddish Proverb
It will be easier for you to detect whether or not your `suspect is lying if one or more of the following factors are present:
- The lie is concerned with an issue that the suspect has strong emotions about.
- The suspect has not anticipated they will be questioned about lying and has not had time to prepare.
- You have a close relationship with the suspect.
- The suspect trusts you.
- There will be an amnesty for the suspect if they confess.
- The suspect has to invent a fictitious account rather than simply withhold information. Commission rather than omission.
- You and your suspect come from similar cultural and national backgrounds.
"The naked truth is always better than the best dressed lie" - Ann Landers
If you want to increase your chances of getting to the truth, then you need to use all of your senses. In his landmark research, Professor Albert Mehrabian established that 55% of our messages are communicated through our physical behavior and appearance, 38% from the sound of our voice, while only 7% of what we actually say, has any impact.
So if you want to accurately interpret the veracity of what your suspect is telling you, you need to adopt a holistic approach to lie detection. This means closely observing your suspect's body language and facial expressions. Listening carefully to how they are speaking, focusing on their pitch and tone. And looking for inconsistencies and discrepancies in the account they are giving.
Because no single behavior can be relied on as an accurate indicator of deception, experienced lie detectors look for `clusters' of signals. A change in a person's physical behavior, coupled with a raising in the pitch of their voice mayindicate stress, which may indicate deception. The more you develop your observation skills the better a lie detector you will become. The best lie detectors are always those with the highest levels of sensory acuity.
There are many steps you can take to develop your lie detection skills. Once you have read this book and learned how to interpret the signals, start people-watching. Do it in a restaurant or public place where you can hear what people are saying. Look at how they use gestures and their body to support what they are saying. Observe their facial expressions.
Watch video clips on YouTube of politicians and celebrities that are believed to be lying. Listen for the vocal indicators and look for the physical signals. And if you are watching a clip where it is widely believed that the person lied, watch with volume turned off. And then reverse things and listen to the liar without looking at the picture.
Arm yourself with as much information about your suspect and alleged deception before you talk to them. Their personality and reputation, history and track record, the context at the time they are alleged to lie, possible motivations. Lawyers and investigators often try to avoid questioning a witness or suspect without knowing the suspect's background first. The more you know, the more accurate you are likely to be in detecting lies.
Table of Contents
- We all want to be lie detectors
- Types of liars and degrees of lying
- You need to be cautious
- Factors influencing detection accuracy
- Setting the scene
- Your body wants to confess
- Eye think you are lying to me
- Time to face the truth
- Listen like a lawyer
- Download the PDF