Article 230-32 of the French Code of Criminal Procedure
Any technical means intended for real-time location, throughout the national territory, of a person, without that person’s knowledge, of a vehicle or of any other object, without the consent of its owner or possessor, may be used if this operation is required by the necessities: 1° An investigation or enquiry into a crime or offence punishable by at least three years’ imprisonment; 2° An investigation or enquiry into the causes…