Article 550 of the French Code of Criminal Procedure
Subpoenas and service, unless otherwise provided by laws and regulations, shall be made by writ of bailiff. Notifications shall be made by administrative means. The bailiff may not instrument for himself, for his spouse, for his parents and relatives and those of his spouse, in the direct line ad infinitum, or for his relatives and relatives in the collateral line, up to and including the degree of cousin descending from…