Postcard from...Paris

Our new Interior Minister, Manuel Valls, was named by the French press this week as one of the great successes of the "Normal", or Hollande, era in French politics. He has managed to appear tough on crime and illegal immigration while reversing some of the authoritarian excesses of the Sarkozy years.

Mr Valls, pictured, is an ambitious man with Latin film-star looks. He was born in Barcelona 50 years ago this month. He is, in other words, himself an immigrant.

One of his edicts to the police and gendarmerie shows how well he understands his adopted country. Mr Valls has ordered all police officers and gendarmes never to say tu – the informal form of "you" – to members of the public.

Tu is an explosive little word. It can be a way of asserting membership of a family or a profession. It can be a term of endearment or it can be an insult. Used by police to young blacks or North Africans, it is the equivalent of the word "boy" in apartheid South Africa or the southern United States.

My wife once heard two Parisian policemen sneeringly calling a young black man tu. He started to tutoie them (call them tu) in return. He was warned that such insulting behaviour could lead to his arrest.

On the other hand, the formal word for you – vous – can also be used to devastating effect.

My teenage daughter once heard a friend say to her mother: "Maman, vous êtes une salope." She was shocked –not so much because her friend had called her mother a "bitch", but that she had addressed her as vous.