Commandeering is an act of appropriation by the military or police whereby they take possession of the property of a member of the public.In United States law, it also refers to federal government actions which would force a state government to take some action that it otherwise would not take. The US Supreme Court has held that commandeering violates the separation of powers principles designed to prevent either the state or federal government from becoming too powerful. Writing for the majority in 1997, Justice Scalia said, "[t]he Federal Government may neither issue directives requiring the States to address particular problems, nor command the States' officers, or those of their political subdivisions, to administer or enforce a federal regulatory program."