McCulloch v. Maryland

McCulloch v. Maryland, 17 U.S. (4 Wheat.) 316 (1819), is a landmark decision of the Supreme Court of the United States that defined the scope of the U.S. Congress's legislative power and how it relates to the powers of American state legislatures. The dispute in McCulloch involved the legality of the Second Bank of the United States and a tax that the state of Maryland imposed on it. In its ruling, the Supreme Court established firstly that the Necessary and Proper Clause of the U.S. Constitution gives the U.S. federal government certain implied powers necessary and proper for the exercise of the powers enumerated explicitly in the Constitution, and secondly that the American federal government is supreme over the states, and so states' ability to interfere with the federal government is restricted. Since the legislature has the authority to tax and spend, the court held that it therefore has authority to establish a national bank, as being "necessary and proper" to that end.

The state of Maryland had attempted to impede an operation by the Second Bank of the United States through a tax on all notes of banks not chartered in Maryland. Though the law, by its language, was generally applicable to all banks not chartered in Maryland, the Second Bank of the United States was the only out-of-state bank then existing in Maryland, and the law was thus recognized in the court's opinion as having specifically targeted the Bank of the United States. The Court invoked the Necessary and Proper Clause of the Constitution, which allows the federal government to pass laws not expressly provided for in the Constitution's list of enumerated powers of Congress if such laws are necessary and proper to further the powers expressly authorized.

McCulloch has been described as "the most important Supreme Court decision in American history defining the scope of Congress's powers and delineating the relationship between the federal government and the states." The case established two important principles in constitutional law. First, the Constitution grants to Congress implied powers to implement the Constitution's express powers to create a functional national government.