He said there is a particular expression that sociopaths and malignant narcissists use much more frequently than normal people: what he calls the Elevated Central Forehead Contraction with a Partial (Insincere) Mouth Smile. It’s a closed mouth, fake smile with the eyebrows drawn together as if the person is frowning. It’s similar to a smirk, but not quite. The overall effect is mocking condescension and cruel contempt. Brown says this expression is used often by serial killers, mass murderers, hardened criminals, and by everyday bullies and other people who lack empathy.