In Italy the Codice delle comunicazioni elettroniche legally bind ISPs to guarantee the functionality and security of the network (both from a physical and logical perspective). This means that if traffic shaping is needed to handle traffic overload this can be done with no specific provision.
Every proposal of nailing down traffic shaping options is a trojan horse because – for instance – copyright lobbies might whistleblow that P2P is creating an international emergency thus forcing ISPs to violate the net neutrality “for security sake”.