How to tell someone's lying to you by watching their face

Samantha Lee/Business Insider
Detecting high-stakes liars is often the work of the FBI, and they frequently look to facial expressions, body language, and verbal indicators as signals, or "tells," that someone is lying.
Mark Bouton, an FBI agent for 30 years and author of "How to Spot Lies Like the FBI," tells Business Insider that he used certain tells to help identify Timothy McVeigh as a suspect in the Oklahoma City bombing. But being able to read facial expressions to detect lies can be beneficial even if you're not conducting criminal investigations, he says.
"There are a number of facial expressions and associated reactions that could indicate someone is lying to you," he says. "Some are caused by nervousness, some by chemical reactions, and others by physical reactions."
To start, he says it's important to understand how the person in question normally acts.
"It's best to observe someone for a while as you make small talk or ask innocuous questions, in order to see what his usual reactions are, including tics he may have," he says. "Then if he exhibits several lying indicators when you ask more pointed or suggestive questions, and these are not ones he previously performed, you can be confident that he's likely lying."
Here are some of the facial expressions Bouton suggests looking out for:
How to find out how much you have spent on Swiggy so far
Mukesh Ambani's Reliance Industries spends Rs 1,184 crore on CSR in 2021-22
In yet another setback to Ola's quality control, a user has alleged that his Ola S1 Pro's front suspension broke while driving
Kia EV6 is now up for pre-booking in India — All you need to know about the futuristic electric vehicle
IT jobs are safer than startup jobs but a salary bubble burst awaits them