In public law, abrogation is the proposing away of a right, power or value, by a public body in delegating power or failing to carry out a responsibility or duty. The abrogation of such a responsibility or duty, unless required by primary legislation would amount to an unconstitutional delegation of power to a foreign government or other sovereign power. It is a protected value at Common Law that Parliament has legislative supremacy even to the point that the sovereign power extends to the breaking of treaties, if need be.