Article D147-37-1 of the French Code of Criminal Procedure
If judicial supervision includes placement under mobile electronic monitoring, the sentence enforcement court or the sentence enforcement judge shall notify the sentenced person, before his release and the installation of the device provided for by article 763-12, that this placement cannot be implemented without his consent, but that, if he refuses it or fails to fulfil his obligations, all or part of the period of sentence reductions he has benefited…