This principle also applies in the public service

Is it possible, in the current state of French law, to prohibit the wearing of the burqa in France

The issue is above all a political question that decision political. But if you want to prohibit the wearing of the burqa, need necessarily to go through the Act because it is a prohibition on the exercise of a public freedom. Three types of arguments could then be invoked: equal, or even the dignity of women; the principle of secularism; Finally, security and public order.As regards the argument of the dignity, it is very difficult legally to use. To put it simply, cannot, in principle, prohibit a person to dress as she wants to for the idea that one of his dignity. It is freedom which prevails. Must be that this person is consenting and the reality of consent will be very difficult to establish.The principle of secularism, there is still more difficult to use. In addition to the link with the exercise of a religion remains to show the free manifestation of beliefs is a constitutional principle. Moreover, prohibit the secularism and outside assumptions where the requirement of neutrality is particularly heavy (education, public services...) would open a Pandora's box regarding the wearing of clothing in public religious.

Is there another possible reason

The principle of public order and security is both relevant and relatively easily invokable: the safety requirement is evident with regard to controls on identity of any kind they are.But, more broadly, everyone has the right, in the public sphere, to identify the person with whom he is related to. Thus all clothing hiding the face of the person so that it renders impossible identification could be prohibited both in relations with public services, payments by card or cheque, or even access to a bank... And, of course, in any situation where the identity of the person is controlled or is likely to be (health, commercial transaction, police, access to buildings...). The assertion of such a principle makes it in fact impractical wearing such clothing in public.

So far, a law yet prohibits the wearing of the veil at school...

The ban in this case is specific and is linked to the requirement of philosophical and religious neutrality in public school. This principle also applies in the public service.

Would a law of prohibition be compatible with the French Constitution and the European convention on human rights

The ban, direct or indirect, of the port of such and such clothing is the personal freedom is a fundamental right as constitutional in conventional terms. However, apart from the fact that dress in public could already be regulated for the public order (e.g. naturism on the beach...), no principle is absolute. The objectives of security and the rights of third parties can justify a limitation of the right to dress freely.The European Court of the human rights, whose jurisprudence is quite respectful State choices on such matters, has already admitted a more restrictive policy than that of the France on wearing religious symbols (judgment in Leyla Sahin v. Turkey - 2005). On the other hand, the convention provides for possible restrictions on the exercise of rights provided that they are prescribed by law and form "of measures necessary in a democratic society to public safety, the protection of the order, health or public morals, or the protection of the rights and freedoms of others". It seems to me that it would be perfectly in this case.