USN not taxable

U.S. Supreme Court
M'CULLOCH v. STATE, 17 U.S. 316 (1819)
February Term, 1819
[17 U.S. 316, 317] ERROR to the Court of Appeals of the State of Maryland. This was an action of debt, brought by the defendant in error, John James, who sued as well for himself as for the state of Maryland, in the county court of Baltimore county, in the said state, against the plaintiff in error, McCulloch, to recover certain penalties, under the act of the legislature of Maryland, hereafter mentioned. Judgment being rendered against the plaintiff in error, upon the following statement of facts, agreed and submitted to the court by the parties, was affirmed by the court of appeals of the state of Maryland, the highest court of law of said state, and the cause was brought, by writ of error, to this court.
The court has bestowed on this subject its most deliberate consideration. The result is a conviction that the states have no power, by taxation or otherwise, to retard, impede, burden, or in any manner control, the operations of the constitutional laws enacted by congress to carry into execution the powers vested in the general government. This is, we think, the unavoidable consequence of that supremacy which the constitution has declared. We are unanimously of opinion, that the law passed by the legislature of Maryland, imposing a tax on the Bank of the United States, is unconstitutional and void.
This opinion does not deprive the states of any resources which they originally possessed. It does not extend to a tax paid by the real property of the bank, in common with the other real property within the state, nor to a tax imposed on the interest which the citizens of Maryland may hold in this institution, in common with other property of the same description throughout the state. But this is a tax on the operations of the bank, and is, consequently, a tax on the operation of an instrument employed by the government [17 U.S. 316, 437] of the Union to carry its powers into execution. Such a tax must be unconstitutional.
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