Under the Articles of Confederation, under which Congress possessed the power to appropriate, there was no independent executive authority. With the creation of an executive under the Constitution, the Founders decided, in the words of Justice Joseph Story in Commentaries on the Constitution of the United States, “to preserve in full vigor the constitutional barrier between each department...that each should possess equally...the means of self-protection.” An important means of self-protection for the legislative department was i
ts ability to restrict the executive’s access to public resources “but in Consequence of Appropriations made by Law.” Justice Story continues:
And the [legislature] has, and must have, a controlling influence over the executive power, since it holds at its own command all the resources by which a chief magistrate could make himself formidable. It possesses the power over the purse of the nation and the property of the people. It can grant or withhold supplies; it can levy or withdraw taxes; it can unnerve the power of the sword by striking down the arm that wields it.
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The courts have consistently recognized the primacy given to Congress by the Appropriations Clause in allocating the resources of the Treasury. As the Supreme Court declared in Cincinnati Soap Co. v. United States (1937),
the Appropriations Clause “was intended as a restriction upon the disbursing authority of the Executive department.” It means simply that
“no money can be paid out of the Treasury unless it has been appropriated by an act of Congress.” In United States v. MacCollom (1976), the Court articulated an “established rule” that
“the expenditure of public funds is proper only when authorized by Congress, not that public funds may be expended unless prohibited by Congress.”