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United States Legal Research for L.L.M. Students

Overview of basic United States legal research. Originally written primarily for foreign law students, who are familiar with legal concepts but unfamiliar with U.S. legal materials, but useful also for the novice practitioner.

Session Laws and Codes

Session laws are the laws of a jurisdiction as passed by the legislature and signed by the executive, collected in chronological order by date of passage. The session laws of the United States are called Public Laws, abbreviated Pub. L., or P.L. Public Laws are cited like this: Pub. L. No. 107-56, where the "107" designates the Congress (the 107th Congress, in this case) and the "56" means the 56th law passed by that Congress.

The Public Laws of the United States are collected in a set of books called the Statutes at Large (abbreviated Stat.). The Statutes at Large are organized in volumes chronologically and are cited like this: 115 Stat. 272, where 115 is the volume number and 272 is the page number within the volume. Pub. L. No. 107-56 is found at 115 Stat. 272.

Codes are collections of the laws of a jurisdiction that are currently in force. Codes are organized by subject. The United States Code is the code of the laws of the United States. It is organized in 53 titles (for example, Title 42 is Public Health and Welfare) and abbreviated as U.S.C. 

Public Laws and Statutes at Large

Print Sources

Online Sources


The laws of the United States are codified in the United States Code (U.S.C.). The U.S. Code is printed every 6 years, with an annual supplement each year in between for updating. Sources: 

Annotated Codes

What is an "annotated code"?  "Annotated" indicates that the editors of the code have added case finding tools, explanatory material, and research resources to the text of the code, to assist the researcher.

Using the U.S. Code

There are several different ways to locate statutes on a particular topic:

1.   Index

2.   Popular Name Tables: find where Public Laws are codified when the information you have is the popular name of the act, e.g. the Clean Air Act.

3.   Tables Volume: includes

  • table to convert Revised Statutes (historical) and Statutes at Large citations to U.S. Code citations
  • table to convert former or revised title citations to current citations
  • table to locate executive orders, proclamations and reorganization plans that are included in the U.S. Code.

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