10 ways you can tell someone is hiding the truth

4. Contradicting Expressions 

While some of us may not be the best at expressing emotions, this may be problematic when telling a lie. According to previous studies, if the timing of the emotions are off, more than likely than not the story is off too. For example, if a person smiles after making a statement instead of smiling simultaneously while making the statement, the emotion is not genuine and neither is the story. To go more in depth, when a person is insincere, they will not use all of the required muscles used naturally to express an emotion—i.e. smiling and frowning.