Sitting on a desk somewhere in the depths of the French interior ministry is a document that, if the ministry would only send it to the local authorities, would make Kouly Konate's life an awful lot easier.
Mr Konate, 59, arrived in France from Mali half a lifetime ago, in 1972. Until a couple of years ago he had a full residence permit and a job in the building industry. He paid taxes and was no trouble to anyone, despite the fact that he was married to two women and had 15 children.
Now, after nearly 30 years' legal residence in France, Mr Konate's 10-year permit has been exchanged for a three-month one. No employer will hire him; banks and post offices look at him askance. Until he divorces either Awa or Hatouba, he is not wanted in France.
"How can I do that?" he asked. "It's not humane, you can't just say to a wife after 20 or 25 years, there is no more marriage between us. And what will she do? Where will she go? I can't afford two homes here and I've nothing in Mali. They've changed their minds and it's not fair, not fair at all."
It is not fair because, like his friend Touamany Diarra and perhaps 10,000 other men in France, Mr Konate told the authorities all about his two wives when they arrived in 1976 and 1981. Both were given residence papers; no one said there might be a problem.
There was even a government directive, in 1980, stipulating that the presence of a foreign national's second wife on French soil was not "contrary to the public order" if he could meet the financial needs of both families.
France, in those days, wanted as many immigrant workers as it could get; it also believed, according to Béatrice de la Chappelle, author of a book on the subject, in their right to a "normal" family life. "Normal, for several thousand families from Mali and Senegal, meant polygamous," she said. "It was never a difficulty."
Now, said Mr Diarra, who lives with two wives and their 11 children in a flat in the Paris suburbs, "Our lives are being made impossible. I have split up my family, I have rented a second apartment for my younger wife and her children, but they are denying her the right to work unless she is divorced."
Under the hardline interior minister Charles Pasqua polygamy was in fact outlawed in France in 1993. The conservative government of the day decided it was one of many foreign customs that were a threat to French society.
No one knows why it took local authorities five or six years to start implementing the loi Pasqua, and it barely matters for those now being targeted by town hall officials who insist, as the law decrees, that work and residence permits "will be denied to a polygamous resident who has brought more than one wife into France".
What exasperates Mr Konate and Mr Diarra is that the law is being applied retroactively, to families who were told on arrival that their marital arrangements were just fine. France can, of course, outlaw polygamy if it chooses. Indeed, many heads of polygamous families in France - and their wives - recognise that the custom does not travel well.
"In Mali, each wife has a separate home for herself and her children," explained Bintou Boiguille of Afrique Parternaire Service (APS), a Paris-based charity that helps polygamous families in difficulty.
"In France, only a very few husbands can afford that_ Forcing two wives to live under the same roof causes unimaginable emotional problems."
Nadia, 40, is one such second wife who has suffered. A member of one of the few polygamous families from North Africa now living in France, she was pushed into an arranged marriage in Algeria with a cousin whose first wife was supposedly very ill.
She arrived in France in 1982, on a tourist visa, to join her husband, his first wife and their four children in a flat outside Paris. A year later, Nadia gave birth to the first of her five children. She loved her husband, she said, and at first she got on well with his first wife.
"But when my children started growing up, things got much worse," she said. "They clashed with her and her children_It became a nightmare."
In 1996, Nadia was one of hundreds of illegal immigrants in France for more than 15 years who went on a month-long hunger strike for their residence papers. She succeeded at the end of 1997 - but was caught up in the crackdown on polygamy. She filed for divorce as the only solution.
For Claudette Bodin, who runs the APS charity, the impossible situation of Mr Konate, Mr Diarra and the rest could be resolved. Thanks to the charity's lobbying, a circular has been drafted by the interior ministry instructing local authorities give polygamous families time to reorganise their lives, to accept a physical separation of the two wives and not to insist on divorce, and to make rehousing second wives a priority.
"But we're coming up to elections next year, and a circular like that won't win many votes," said Ms Bodin. "So it hasn't been sent out. In the meantime, Kouly Konate doesn't know how to feed his family - men of 50, 60 years old, who have worked all their lives, are having to steal food. This problem is of the government's making, not theirs."