When Jean-Jacques Reboux was stopped in his battered Citroën AX by police in Paris and accused of obstructing the traffic, he protested his innocence. “I was in a traffic jam at a crossroads and I wasn't obstructing anything at all,” he told The Times.

First, Mr Reboux called the police officer a canard (a duck). Then he lost his cool and called him a connard, which translates roughly as stupid bastard.

The term landed the Parisian publisher in court and he was fined €150 (£118) this month for the peculiarly Gallic crime of outrage, or insulting a public official.

The offence — which carries a maximum sentence of six months in prison and a €7,500 fine — dates from Napoleonic times and is designed to protect “the dignity ... of a person charged with a public service mission”.

Behind the legalese is the belief that civil servants are the embodiment of a French State that deserves the respect and support of all its citizens. The number of prosecutions for insulting police officers and other civil servants has risen from 17,700 in 1996 to 31,731 last year in what critics say is an abuse of government power.

Now Mr Reboux has begun a high-profile campaign for outrage to be taken off the criminal statute books.

“If you tell the owner of your local café or your banker that he's a connard, you might get into a row but you won't get prosecuted,” the mild-mannered intellectual said. “But if you say the same thing to a policeman, you find yourself in court. Why should civil servants be different? It's like something from the ancien régime.”

Mr Reboux has founded the Association for the Decriminalisation of the Offence of Outrage with Romain Dunand, a left-wing activist from eastern France who also believes that he was a victim of injustice.

Mr Dunand wrote a private e-mail to one of President Sarkozy's advisers comparing government immigration policy to that of the Vichy administration, which collaborated with the Nazis during the Second World War. The upshot was an €800 fine for insulting the head of state.

Mr Dunand is not alone in facing prosecution for outrage involving the President. A homeless man was given a one-month prison term for shouting out that Mr Sarkozy — Interior Minister at the time — was a “bloody Hungarian” in reference to his family origins. A 21-year-old was given a similar sentence for insulting the President's mother.

Amid a drive to reassert the authority of the State, Mr Reboux said, politicians and civil servants were increasingly quick to claim that they had been the victims of insults — especially as they could seek damages ranging from several hundred to several thousand euros.

Post office employees, tax inspectors, railway staff and teachers are all starting to file lawsuits when they believe that they have been slighted.

Even Gérard Depardieu has fallen foul of the law. A description of three work inspectors as “jokers” when they raided the film set where the actor was performing left him with him a €3,500 fine.

Nicolas Comte, general secretary of the Workers' Force Police Officers' Union, said that prosecutions for outrage were increasingly common only because insults were increasingly common.

“If we got rid of this offence, it would be an open door for those who want to insult police officers. The problem is that the relationship between the police and the population is more and more difficult these days.”

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