United States constitutional law is the body of law governing the interpretation and implementation of the United States Constitution. The subject mainly concerns the scope of power of the United States federal government as compared to the individual states and the fundamental rights of individuals. As the ultimate authority on matters of constitutional interpretation, the decisions of the Supreme Court of the United States make up a large portion of constitutional law.
Interpreting the Constitution and the authority of the Supreme Court.
The power of judicial review.
Early in its history, in Marbury v Madison, (1803) and Fletcher v Peck, (1810), the Supreme Court of the United States declared that the judicial power granted to it by Article III of the United States Constitution included the power of judicial review, to consider challenges to the constitutionality of a State or Federal law. According to this jurisprudence, when the Court measures a law against the Constitution and finds the law wanting, the Court is empowered and indeed obligated to strike down that law. In this role, for example, the Court has struck down state laws for failing to conform to the Contract Clause (see, e.g., Dartmouth College v Woodward) or the Equal Protection Clause (see, e.g., Brown v Board of Education), and it has invalidated federal laws for failing to arise under the Commerce Clause of the Constitution (see, for example, United States v Lopez).
Scope and effect.
The Supreme Court's interpretations of constitutional law are binding on the legislative and executive branches of the federal government, on the lower courts in the federal system, and on all state courts. This system of binding interpretations or precedents evolved from the common law system (called "stare decisis"), where courts are bound by their own prior decisions and by the decisions of higher courts. While neither English common law courts nor continental civil law courts generally had the power to declare legislation unconstitutional (only the power to change law), the United States Supreme Court has long been understood to have the power to declare federal or state legislation unconstitutional.
