A Frenchman is fighting to overturn a ban on passport photos which show the person smiling, claiming the rule is keeping people depressed.

A citizen who French media are calling "Thierry" has gone to court to challenge the regulation.

He took up the case after his Mona Lisa-esque passport photo was rejected because it showed a "slightly ironic grimace that borders on a discreet smile", according to Le Parisien.

The man, understood to be a 40-year-old senior civil servant, has accused the French state of "abuse of power".

In a letter sent to French news agency AFP, the man asks: "Is it responsible, in a depressed France, for the authorities to accuse people if they smile?"


French passport rules, like those in the UK, state that: "The subject must adopt a neutral expression and should not smile."

The British rule is understood to have been brought in with the introduction of biometric passports which allow the features of a face to be compared with those held in a database.

Because the width of a smile varies, it can leave facial recognition technology unable to verify a person's identity.

The lawyer for "Thierry", Romain Boulet, claims a previous court judgment that banned smiling was incorrect and based on a note with no legal value.

Image: The man says smiley photos would "give the French a friendly face" at airports

He argues the law simply states that subjects must look at the camera, maintain a neutral expression and keep their mouths shut - with no mention of not smiling.

In his submission, Mr Boulet referred to Leonardo da Vinci's Mona Lisa, famous for its subject sporting an enigmatic half-smile.

For over 500 years people have wondered if the Mona Lisa is smiling," said the lawyer.

"That so many leading experts have failed to agree on this, shows that it is not (for) the authorities to determine whether a smile is neutral or not."

Allowing French people to smile on their passport photos would "give the French a friendly face" when they arrive "at borders around the world", Mr Boulet added.