The following techniques to telling if someone is lying are often used by police, and security experts. This knowledge is also useful for managers, employers, and for anyone to use in everyday situations where telling the truth from a lie can help prevent you from being a victim of fraud/scams and other deceptions.
I was doing some reading on this a while ago and found that many of their items, like “will not look you in the eye” and poor indications. Most practical and learnable lie detection skills come from analysis of facial muscles and eye movements.
It is true that a lot of what was listed is used by police. My father-in-law was a state cop and said they had training with similar suggestions. Too bad the police are still following outdated practice.