During the last three decades of the 19th century, extradition was a highly debated issue, both in the legal and political sphere. The study of the debates amongst international lawyers, who gathered in the Institut de droit international and in the International Law Association makes it possible to specify what was. at stake then. Most of the participants in these debates consider that the practice must be redefined and codified because the intensification of circulations makes its a necessary tool for penal justice. These liberal circules wish however to avoid liberal states giving up their right to protect exiles. The task is made difficult by the anarchist upsurge of the century leading them to define a balance that would make it possible to hunt down the criminal and the anarchist without rejecting exiled freedom fighters. They succeed in doing so, after several decades of debate, only at the cost of criminalizing the anarchist movement’s mores, thus elaborating an international norm, the traces of which can be found in the domestic law and practices of the north-western European states. The connection between international standards and national practices is ensured by agents, of which Louis Renault is a good example for France, who simultaneously occupy dominant positions in the international sphere and the domestic legal order.