Do actors bias the judgments of lie detectors more than non-actors?

The ability of actors and non-actors to influence truthfulness judgments of their statements was investigated. Students judged the truthfulness of true and false statements made by actors and non-actors. The actors were considered more truthful when they were lying, whereas the non-actors were considered more truthful when they told the truth. Analysis of actors and non-actors' behavior indicated that lying actors produced full (felt) smiles and suppressed half (feigned) smiles. Actors also suppressed bodily movements in making both truthful and false statements. It was suggested that actors were able to suppress behavioral cues that are erroneously believed to indicate deception.