Brown v. Maryland, 12 Wheaton (25 U.S.) 419; 6 L. Ed. 678 (1827)
Facts—A Maryland law required all importers of foreign goods to have a license issued by the state. The indictment in this case charged Brown with having imported and sold some foreign goods without having a license to do so.
Issue—Can the legislature of a state constitutionally require the importer of foreign goods to take out a license from the state before he shall be permitted to sell the goods imported?
Decision—C.J. Marshall (6–1). The powers remaining with the states as a result of the Constitution may be so exercised as to come in conflict with those vested in Congress. When this happens, that which is not supreme must yield to that which is supreme. It results necessarily from this principle that the taxing power of the states must have some limits. The Maryland statute authorizing a tax on imports interfered with the federal government’s control of commerce with foreign countries. Although not denying the right of a state to tax property within the state, state taxing of imports would derange the measures of Congress to regulate commerce, and affect materially the purpose for which that power was given. “It is sufficient for the present to say, generally, that when the importer has so acted upon the thing imported, that it has become incorporated and mixed up with the mass of property in the country, it has, perhaps, lost its distinctive character as an import, and has become subject to the taxing power of the state; but while remaining the property of the importer, in his warehouse, in the original form or package in which it was imported, a tax upon it is too plainly a duty on imports to escape the prohibition in the Constitution.” The Court held the action of Maryland also to be contrary to the provision in the Constitution expressly forbidding states to tax imports.