RESEARCHERS at a Scottish university say an ancient Roman “lie detector” made famous by an Audrey Hepburn film was nothing more mysterious than a drain cover.
Legend has it the Bocca della Verita, “Mouth of Truth”, will bite anyone who lies while their hand is inside the mouth of the marble carving.
It featured in the 1953 film Roman Holiday starring Audrey Hepburn, which brought the medieval legend that it could be used as a lie detector to a global audience.
But Dr Fabio Barry of St Andrews University says the face depicted river god Oceanus, and was a drain cover commissioned by the emperor Hadrian.
The Bocca, located in the church of Santa Maria in Cosmedin, Rome, dates back to the second century and has holes in its mouth, eyes and nostrils.
Thousands of couples visit the site every year to try their hands at the lie detector test and prove their honesty to each other.
According to Dr Barry, they are merely dipping their hands in a Roman drain cover.
Dr Barry, an art historian who is half Italian, said: “The famous scene in the film Roman Holiday, where Gregory Peck gets Audrey Hepburn to put her hand in the ‘Bocca’ because he knows she is hiding the truth about her identity, sums up at least five centuries of tradition in a minute and a half: what is first recorded as a chastity or fidelity test in 1450 had become a general lie detector by 1800.
“Today, droves of expectant tourists still line up to try their hands at it.
“But it is an enduring irony that the myth continues to prosper, because while the ‘Bocca’ condemns the lies of others, it refuses to disclose its own secret.
“Despite its worldwide fame, we know next to nothing about the original meaning of the ‘Mouth of Truth’.
“For three centuries, archaeologists have attempted to identify the face on this marble disk as Jupiter, Mercury, the Nile and even a totem of a man-eating lion from Asia Minor, but without ever reaching any consensus.”
Remarkably, although Dr Barry had seen the Bocca countless times, it was only after looking at a postcard sent by his late mother from Rome that the true identity of the famous face dawned on him.
He said: “I was working in the National Gallery in Washington DC, and I had the postcard pinned over my desk.
“From time to time I would glance at it when I got bored with whatever I was writing.
“One day I noticed the face had horns, and that they were forked like crab pincers.
“I immediately grabbed a lexicon of mythological imagery and realised that this face could only be Oceanus, the god who personified the unending river that was believed to surround the flat earth like a moat.”
He said the Bocca was originally a drain cover for a temple or religious area dedicated to Hercules on the present site.
A spokesman for the Italian State Tourist Board said: “Whatever conclusions researchers draw, the Mouth of Truth will always have popular appeal.