Drug dealers, illegal arms salesmen and purveyors of dangerously dodgy secondhand cars might have thought all their Christmases had come together last week.

If the principles behind a new law on prostitution that was passed in France were to be applied to those criminal enterprises, the operators will, in future, be deemed as innocent as a newborn baby in the eyes of the law.

Only the customer who buys their wares will feel the heat of the bogey’s hand on his collar and the custodial consequences of the beak’s displeasure.

This unusual approach to criminal responsibility – reversing legal tendencies that have developed for decades in the West to protect the customer – will be the obvious, logical outcome of France’s latest regulations governing prostitution.

In that country, in future, seeking to buy sex will be illegal while offering sex for sale incurs no criminal consequence. The legislators have, they say, legalised prostitution while outlawing the financial transaction on which the trade subsists.

This development follows the passing of similar laws elsewhere in Europe. Sweden was the first country to criminalise those who pay for sex rather than the prostitutes, introducing a law to that effect in 1999.

Norway followed in 2008, Iceland in 2009 and Northern Ireland in 2014. The European parliament has adopted a resolution calling for this legal approach to be adopted throughout the continent.