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Constitutional Law: An Overview

The broad topic of constitutional law deals with the interpretation and application of the United States Constitution. As the Constitution is the source of legal authority for the United States, questions of constitutional law often relate to fundamental questions of sovereignty and democracy. 

The Supreme Court has authority to conclusively decide questions of constitutional law through their power of judicial review. Judicial review allows courts to declare actions of governmental bodies unconstitutional and, therefore, prevent the actions from being enforced. Consequently, study of constitutional law focuses heavily on Supreme Court rulings. 

The Constitution follows a system of enumerated powers and separation of powers between three branches of the federal government (executive, legislative and judicial). Structurally, these three branches are designed to check and balance any potential overreach of power by the other branches. The text of the Constitution is split between 7 Articles and a collection of underlying sections. 

The Articles

Article I of the Constitution establishes the Congress; including the bicameral House of Representatives and the Senate, and Section 8 lists the powers Congress possesses. Due to the wide interpretation of some of these powers, namely the Commerce Clause, the Constitution grants Congress wide reaching authority to pass laws on a variety of topics. That said, Section 9 of Article I prohibits Congress from taking certain actions.

  • For example, until the passage of the Sixteenth Amendment, Congress could not directly tax the people of the United States unless it was proportioned to the population of each state.

Section 10 of Article I is unique in that it directly applies to the states rather than the federal government. This section prevents states from taking certain actions which are reserved exclusively for the Congress.

Article II of the Constitution establishes the executive branch of government and the office of the Presidency. Unlike Article I, Article II is less specific with the powers it grants the President.

  • Section I grants the office general "executive" power.
  • Section 2 establishes the office as the "commander in chief" and empowers it to grant pardons, except in cases of impeachment, for offenses against the United States.
  • Section 3 provides the power to make treaties (with the advice and consent of two-thirds of the Senate) and the power to nominate ambassadors, ministers, Judges of the Supreme Court, and all other Officers of the United States. 

Article III mandates the creation of the Supreme Court and permits the rest of the judicial branch of the federal government.

Article IV governs relationships between the various states. Section I the Constitution contains the "full faith and credit clause.” This clause provides that each state must recognize the public acts (laws), records, and judicial proceedings of the other states. Section 3 permits the addition of new states and lays out the process by which they will be added.

Article V of the Constitution authorizes the federal government to make changes to the Constitution in conjunction with the states by passing amendments. To pass an amendment, the proposed amendment must first pass-through Congress and must then be ratified by at least 3/4ths of the states.

  • As of 2022, the Constitution has been amended twenty-seven times.

Article VI establishes federal law as dominant over state law through what is known as the Supremacy Clause. Due to article VI, state laws which directly contradict federal law are not enforceable. Furthermore, all federal, state, and local officials must take an oath to support the Constitution.

  • This means that state governments and officials cannot take actions or pass laws that interfere with the Constitution, laws passed by Congress, or treaties.

Article VII establishes how the Constitution will initially take effect. 

Amendments to the Constitution

As mentioned above, the Constitution has been amended 27 times since it was first passed. 

The first ten amendments, called the Bill of Rights, were ratified in 1791 and provide a check on the federal government. The first eight amendments prevent the federal government from infringing upon certain rights of individuals.

The exact implications of each of these rights has been the subject of wide debate and controversy. As a result, an exhaustive list of case law exists interpreting what each amendment entails.

  • For example, in District of Columbia v. Heller, the Supreme Court held that the Second Amendment prevents a government from interfering with a person’s ability to possess firearms for self-defense purposes, regardless of their status as a militia member. 

The Ninth and Tenth Amendments are typically interpreted to show that the power of the federal government is not absolute.

  • The Tenth Amendment specifically states that "the powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people."
  • The Ninth Amendment also guarantees that the "enumeration . . . of certain rights [in the Constitution] shall not be construed to deny or disparage others retained by the people."

The Thirteenth Amendment made chattel slavery illegal. The Fourteenth Amendment, which was passed in conjunction, prohibits the states from abridging "the rights and immunities" of any citizen without due process of law, as well as guarantees equal protection of the law for all citizens. The due process clause, as this has since become known, has had wide reaching effects on the field of constitutional law due to how it has been interpreted. 

  • For example, the Supreme Court has interpreted the due process clause of the Fourteenth Amendment as affording citizens protection from interference by the state with almost all of the rights listed in the first eight amendments.
  • This process of extending the Bill of Rights to the states is called the incorporation doctrine.
  • Additionally, interpretations of the 14th amendment led to the creation of the substantive due process doctrine. 

The right to vote is protected by the Fifteenth Amendment ("right to vote shall not be denied... on account of race."), the Nineteenth Amendment (guaranteeing the right to vote regardless of sex), the Twenty-Fourth Amendment (outlawing the practice of poll taxes), and the Twenty-Sixth Amendment (extending the right to vote to 18 year olds).  

Amendments Seventeen, Twenty, and Twenty-Five provide procedures for filling vacancies in the legislative and executive branches. 

Finally, the Twenty-Seventh Amendment prevents laws that change the compensation received by Congress from taking effect until the next election occurs. 

[Last updated in August of 2022 by the Wex Definitions Team]

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