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United States of America Law

Introduction to Federal Legislation

Federal legislation begins as a bill introduced in Congress.  A bill becomes law after the President signs it or Congress enacts it over the President’s veto.  After a bill is enacted into law, the new statute is published in three different forms: slip laws, session laws and codes. 

The first official publication of a statute is in the form of a slip laws.  A slip law is a separate copy of an individual law published as an unbound pamphlet.  Each slip law contains an assigned law number (public or private law number), the bill number, a legal statutory citation, and the date of approval. 

Session laws are the compilation of all statutes passed by Congress within a given session.  Session laws are compiled at the end of each Congressional session when the slip laws for that session are chronologically compiled into bound volumes called Statutes at Large

Codes are compilation of current permanent laws arranged according to subject matter.  They bring together related laws and incorporate amendments into the existing topical arrangements.  The codes for federal legislation is known as the United States Code.

When researching federal legislation, use slip laws, session laws and codes for different research needs. Use the U.S. Code to find the current law on a particular topic as it incorporates all amendments and related laws together.  Use session laws (Statutes at Large) for researching legislative history as they provide the law in force at a particular point in time.  Use slip laws to keep up to date with new legislation as they are the first publication for any new statute, which may not yet have been incorporated into the U.S. Code.

The Legislative Process


The video below is a nine-part series which explains each of the common legislative stages, and the process by which a bill becomes law.

For additional information on the legislative process

Annotated U.S Code

The U.S. Code is the official consolidation and codification of all general and permanent laws of the United States.  It is organised according to subject matter into titles.  The U.S. Code is the most frequently consulted statutory source, and comes in two versions: unannotated and annotated.  The unannotated U.S. Code (USC) is the official version and should be cited whenever possible.  The annotated code, however, includes references to regulations, case law, treaties, and laws enacted by state and local governments that have interpreted, construed or applied a particular code section.  For this reason, legal researchers should use the annotated version of the code to begin their research.  


Unannotated U.S Code

The unannotated U.S. Code (USC) is the official version and should be cited whenever possible.  The Office of the Law Revision Counsel publishes the official online and most current version of the code.  The Government Publishing House publishes the official print version of the code every six years with cumulative supplements annually.  If you are referring to the print version of the code, please be aware that it may be out-of-date.  You may need to refer to the annual supplements and possibly session laws to determine its currency. 

Session Law (Statues at Large)

All of the laws passed by the U.S. Congress in a particular session are known as session laws.  They are compiled, in chronological order, into bound volumes called Statutes at Large.  Every public law passed by Congress is published in the Statutes at Large.  Each public law is assigned a Pub. L. number, which indicates the session of Congress in which the law was passed, e.g. Pub. L. 113-75 is the 75th public law passed by the 113th Congresss.  Also included in the Statutes at Large are concurrent resolutions, proclamations by the President, private laws, proposed and ratified amendments to the Constitution, and reorganization plans. 

Statutes at Large is the official source for federal session laws.  Westlaw also publishes an unofficial version of session laws called the United States Code Congressional & Administrative News (USCCAN), which can be accessed online. 

Use session laws session laws for historical research, and as proof of statutory enactment, amendment and repeal. 

Session Laws (Slip Laws)

The first official publication of a statute is in the form of a slip law.  If you cannot find session laws in the Statutes at Large, it is probably because the slip laws for that particular Congressional session has yet to bound in print.  You can find unbound slip laws for recent years at:

Free Databases of U.S Legislation

Judicial Consideration of Legislation

To find court cases that have considered a piece of legislation, look at the annotated codes.  For more information, see Annotated U.S. Code box to the right.

Federal Legislative History Research

If you need to track the status of a federal bill, determine the legislative intent, or to better understand the meaning of a statute, you need to undertake legislative history research.  Congressional documents that form the legislative history of a statute may include different versions of the bill, committee hearings, reports, debates and presidential signing statements.  Congressional Committee reports generally provide the most authoritative information about legislative intent.

Use the following resources to conduct legislative history research:

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