Oglesby v. Adams

“Contracts to which a State is a party are within the constitutional prohibition against the impairment of the obligation of contracts. An act of a legislature may be an obligation of the State within the constitutional prohibition, and whatever rights are created by such act a subsequent legislature cannot impair. It is a well established principle that a contract to which a State, or a subdivision thereof, is a party is as much within the constitutional prohibition of statutes impairing the obligation of contracts as a contract between individuals, particularly with respect to contracts…