Article R53-20 of the French Code of Criminal Procedure
Where it has not been taken in the course of the investigation, enquiry or trial proceedings, the sample shall be taken, on the instructions of the public prosecutor or the public prosecutor and in accordance with the procedures set out in I of Article 706-56, within one year at the latest: 1° Either, if the person has been definitively sentenced to a penalty, from the end of the execution of…