Since the adoption of the European Convention on Human Rights and, above all, since the implementation of the European Court of Human Rights, national criminal law has been constrained. The legal authorities of the Member States must respect a certain number of obligations provided for by the text and interpreted by the European jurisdiction. If this is not the case, the applicants can appeal at the Court of Strasbourg and demand compensation for the violation of their fundamental rights. This is how the European Court, through its many decisions, has enabled a certain harmonization within the Council of Europe, which is now made up of 47 States. France does not escape condemnation. Even if it has sometimes resisted the Court’s injunctions, the latter’s judgments have nonetheless obliged France to contain its incriminations and to limit the restrictions on the rights of persons placed in detention. Freedom of expression is quite a remarkable illustration of the necessary delimitation of incriminations. While the Court accepts that States retain a margin of appreciation, it exercises an attentive and rigorous eye when States reduce the exercise of this freedom. The balance is always difficult to determine, but it must be right. Concerning the rights of detainees, the Court seems more flexible regarding States and hesitates in its positions. However, even if there is a restriction of freedoms, the incarcerated individuals remain citizens. They must therefore be able to exercise a certain number of rights. This is linked to their status as subjects of law.