The United States of America has a federal system under which the 50 states have agreed to give the federal government certain powers spelled out in the U.S. constitution. All powers not granted to the federal government in the constitution are reserved to the states. Laws are made at three levels federal, state, and local. The Constitution creates a federal government comprised of three separate and equal branches, and each are sources of law: legislative, executive, and judicial.  In addition to the information below, the Law Library of Congress provides a helpful guide to federal legal materials.


The Constitution is the founding document for the United States federal government. The text of the Constitution is available in numerous resources, including:

  • American Memory (Library of Congress) Find documents from the Continental Congress and Constitutional Convention (1774-1789), includes images of original documents and related materials. 
  • Founder’s Constitution (University of Chicago Press) Provides links to historical documents related to the development of the Constitution. 
  • LII: CRS Annotated Constitution Prepared by the Congressional Research Service, provides links to Supreme Court opinions, the U.S. Code, and the Code of Federal Regulations.
  • National Archives Images of original documents and historical information. 

    Executive Branch:

    See also Law Library Research Guide: Federal Administrative Law

    The power of the executive branch is vested in the President, who also serves as Commander in Chief of the Armed Forces. The President appoints the Cabinet and oversees the various agencies and departments of the federal government. While federal administrative agencies are given the scope of their authority by Congress, they are part of the Executive Branch. 

    In order for a person to become President, he or she must be a natural-born citizen of the United States, be at least 35 years of age, and have resided in the United States for at least 14 years. Once elected, the President serves a term of four years and may be re-elected only once. The President can issue Executive Orders to direct the actions of the federal agencies or to set policies for the executive branch to follow. 

    Executive Orders & Other Presidential Documents

    Presidential documents include executive orders and proclamations. These may be found in the Federal Register and in Title 3 of the Code of Federal Regulations. The most comprehensive source for presidential documents is the Compilation of Presidential Documents (consists of weekly and daily compilations). This contains executive orders and proclamations as well as nominations, announcements, transcripts of speeches, and press conferences. Another useful resource containing a variety of presidential documents is the Public Papers of the Presidents.

    Judicial Branch:

    The judicial branch hears cases that challenge or require interpretation of the legislation passed by Congress and signed by the President. It consists of the Supreme Court and the lower federal courts. Appointees to the federal bench serve for life or until they voluntarily resign or retire.

    The Supreme Court is the most visible of all the federal courts. The number of Justices is determined by Congress rather than the Constitution, and since 1869, the Court has been composed of one Chief Justice and eight Associate Justices. Justices are nominated by the President and confirmed by the Senate.

    The federal courts often are called the guardians of the Constitution because their rulings protect rights and liberties guaranteed by it. The federal courts interpret and apply the law to resolve disputes. The courts do not make the laws. That is the responsibility of Congress. Nor do the courts have the power to enforce the laws. That is the role of the President and the many executive branch departments and agencies.

    U.S. Supreme Court

    U.S. Circuit Courts of Appeal

    U.S. District Courts  

    Legislative Branch:

    See also Law Library Research Guide: Federal Legislative History

    The legislative branch of the federal government consists of the Congress, which is divided into two chambers: the Senate and the House of Representatives. Each member of Congress is elected by the people of his or her state. The House of Representatives, with membership based on state populations, has 435 seats, while the Senate, with two members from each state, has 100 seats. Members of the House of Representatives are elected for two-year terms, and Senators are elected for six-year terms.

    When Congress passes a bill that is signed by the President the document is given a Public Law Number (ex. P.L. 100-53 refers to the 53rd law passed by the 100th Congress). Public laws are then published, chronologically, in the United States Statutes at Large (Stat.).  These statutes are then codified---organized by subject---in the United States Code. The Office of Law Revision Counsel is responsible for this codification. 



      Last Updated May 6, 2015