The power of the courts to declare laws or actions unconstitutional was established by which case in 1803?

• A. Marbury v. Madison
• B. McCulloch v. Maryland
• C. Brown v. Board of Education
• D. Gibbons v. Ogden

Answer: (A)

Judicial review—the power of the courts to strike down laws or actions that conflict with the Constitution—was established in Marbury v. Madison in 1803. In that decision, Chief Justice John Marshall argued that the Constitution is the supreme law of the land and that it is the duty of the judiciary to interpret what the law requires. The ruling held that some acts of Congress exceeded constitutional authority, and therefore could be voided by the courts. This decision sets the precedent that the judiciary acts as a check on both the legislature and the executive by reviewing the constitutionality of laws and government actions.

The other cases illustrate different constitutional principles. McCulloch v. Maryland dealt with federal supremacy and implied powers of Congress, Brown v. Board of Education addressed equal protection and the end of racial segregation in schools, and Gibbons v. Ogden focused on regulating interstate commerce. None of these established the specific power of the courts to declare laws unconstitutional, which is why Marbury v. Madison is the defining case for this authority.