La Bocca della Verità (Italian: the Mouth of Truth) is a river god used to be a drain cover, but since the Middle ages, served as a lie detector.

It was believed that if one told a lie with his or her hand in the mouth of this god, it would be bitten off. Of course it had to be helped sometimes by a servant with a blade. The Bocca was placed in the portico of the Santa Maria in Cosmedin church in Rome, Italy in the 17th century.

The sculpture is thought to be part of a roman fountain or perhaps a "manhole" cover.