The broad topic of constitutional law deals with the interpretation and implementation of the United States Constitution. Constitutional law deals with some of the fundamental relationships within our society, including the relationships among the states, the states and the federal government, the three branches (The Executive, Legislature, Judiciary) of the federal government, and the rights of the individual in relation to both federal and state government. The Supreme Court plays an important role in interpreting the Constitution. States have constitutions of their own, but the case of Marbury v. Madison (1803) firmly established the power of the Supreme Court to strike down federal statutes it found unconstitutional, making the Supreme Court the final arbiter of constitutional interpretation. The "equal rights" provision of the 14th Amendment established that the rights in the first ten amendments ("Bill of Rights") applied to state governments.
The Constitution establishes the three branches of the federal government and enumerates their powers. Article I establishes the House of Representatives and the Senate. See U.S. Const. art. I. Section 8 enumerates the powers of Congress. Congress has specifically used its power under the commerce clause to regulate commerce with foreign nations and among the states by passing broad and powerful legislation throughout the nation. The sixteenth Amendment gives Congress the power to collect a national income tax without apportioning it among the states. Section 9 of Article I prohibits Congress from taking certain actions.
Article II of the Constitution establishes the presidency and the executive branch of government. The role of the Supreme Court and the rest of the judicial branch of the federal government is covered by Article III. Article V of the Constitution provides the procedures to be followed to amend the Constitution. There have been 27 amendments to the Constitution to date (including the Bill of Rights).
Article VI, the Supremacy Clause of the United States Constitution, states that the "Constitution, and the Laws of the United States which shall be made in Pursuance thereof; and all treaties made or shall be made, under the Authority of the United States, shall be the Supreme Law of the Land." The first section of the fourth article of the Constitution contains the "full faith and credit clause", requiring that each state must recognize the public acts (laws), records, and judicial proceeding of the other states. The Fourth Article also guarantees that a citizen of a state be entitled to the "privileges and immunities" in every other state.
The first ten amendments, called the Bill of Rights, were enacted in 1791 to provide a check on the new federal government. These rights include some of the fundamental rights on individuals, such as freedom of speech and due process in application of the laws. Other rights granted in the Constitution include: writ of habeas corpus, no bill of attainder, no duties or taxes on transporting goods from one state to another (Article I, Section 9); jury trials (Article III, Section 1); freedom of religion, speech, press (which includes all media), assembly and petition (First Amendment); state militia to bear arms (Second Amendment); no quartering of troops in homes (Third Amendment); no unreasonable search and seizure (Fourth Amendment); major ("capital and infamous") crimes require indictment, no double jeopardy (more than one prosecution) for the same crime, no self-incrimination, right to due process, right to just compensation for property taken by eminent domain (Fifth Amendment); in criminal law, right to a speedy trial, to confront witnesses against one, and to counsel (Sixth Amendment); trial by jury (Seventh Amendment); right to bail, no excessive fines, and no cruel and unusual punishments (Eighth Amendment); unenumerated rights are reserved to the people (Ninth Amendment); equal protection of the laws (14th Amendment); no racial bars to voting (15th Amendment); no sex bar to voting (19th Amendment); and no poll tax (24th Amendment)