The French upper house of parliament, the Senate, began to debate Wednesday a controversial immigration bill which would authorise voluntary DNA testing on foreigners wishing to join their families in France.
The debate, which opened overnight, was to resume in the afternoon after the government made new concessions to win over critics. These include the left-wing opposition, but also some government supporters, as well as religious leaders and campaigning groups.
On Tuesday the chief executive of the African Union, Alpha Oumar Konare, added his voice to the bill's opponents, describing the proposed DNA tests as "unacceptable at an ethical, moral and cultural level."
Supporters say the measure would make it possible for would-be immigrants to speed up the application process by proving their kinship with family-members in France. They point out that 12 other EU countries carry out similar tests. However opponents say it would set a dangerous precedent by making genetic affiliation a criterion for citizenship.
The measure - part of a wider immigration bill - has been approved by the lower house, the National Assembly, but it was rejected last week when it was examined by the Senate's laws committee. That decision can be overturned by a vote in plenary session. Immigration Minister Brice Hortefeux has backed a series of concessions in order to convince waverers.
Under the changes, DNA tests will only be permitted in countries where civil status documents - otherwise the main proof of kinship - are known to be widely counterfeited. And the measure would only be authorised for two years, ahead of an evaluation by an expert panel.
Overnight Hortefeux gave new ground. Under the latest formulation, the cost of the tests will be borne entirely by the French state - in order to avert the charge that they discriminate against poor families. And applicants' DNA will be compared only with their mothers' - this to avoid the danger of intrusive revelations about paternity.
Defending the text late Tuesday, Hortefeux said the aim of the tests was "to give a new right to foreigners of good faith" and he "refused to allow people to caricature a text which the government wants to be fair and protective."
For some critics, the measure fails to take into account the loose nature of African families. For others, it evokes bad memories of France's World War II past, when the Vichy government collaborated with the racial policies of the Nazis. "This type of law is unacceptable, it has no place in our society. Our memory, our history, should lead us to condemn this kind of legal arsenal, given all that we have seen - the round-ups, the rejection of the other," said former prime minister Dominique de Villepin.
The DNA clause was not part of Hortefeux's original immigration law, whose principle measures are to impose new financial and linguistic demands on would-be immigrants seeking to join families in France.
It was introduced as an amendment by Thierry Mariani, a member of the ruling Union for a Popular Movement (UMP), and only cautiously taken up by the government. President Nicolas Sarkozy has refused to comment on the proposal.