Um.... There's no law doing what now? [0]
Loi no 2001-1062 du 15 novembre 2001 relative à la sécurité quotidienne, article 30 (Law #2001-1062 of 15 November 2001 on Community Safety) allows a judge or prosecutor to compel any qualified person to decrypt or surrender keys to make available any information encountered in the course of an investigation. Failure to comply incurs three years of jail time and a fine of €45,000; if the compliance would have prevented or mitigated a crime, the penalty increases to five years of jail time and €75,000.[22]
https://en.wikipedia.org/wiki/Key_disclosure_law#France