Statutes are laws enacted by a legislative body. Statutes may also authorize administrative regulations and can overturn or modify court decisions that are sometimes concerned with statutory interpretation. In the United States, both the U.S. Congress and individual state legislatures have the power to pass statutes.
Remember: not all legal issues are governed by statute. Part of statutory research is determining whether or not a statute applies to a particular question or area of law.
After a statute is passed by the legislature, it is published in three forms:
Slip laws: individual pamphlets containing the text of a law as passed
Session laws: annual compilations of laws passed in a legislative session
Codes: compilations of the laws in effect, organized by subject
Slip laws are the first version of a statute to be printed or appear online:
Slip laws may include:
Next, slip laws from a single legislative session are collected and published in date order as session laws.
*but see the note on positive law codification below.
Codes organize the law and
Codes come in different formats:
The United States Code (U.S.C.) is the official, unannotated code of the United States, and is published (in print) every six years with annual cumulative supplements. As of 2022, the U.S.C. is divided into fifty-four major topics called titles.
For efficient research, use an annotated code.
Annotated codes are powerful research tools. They include:
Some titles of the U.S. Code have been enacted as positive law. This means that a whole code title has been restated and passed as a Federal Statute. A positive law title supersedes earlier enactments and serves as legal evidence of the text of a law. A non-positive law title is a compilation of laws from the Statutes at Large. It serves as "prima facie" evidence of the law, but can be rebutted by the text of the Statutes at Large.
For more details and a current list of positive law titles and codification projects, see the Office of the Law Revision Counsel's web page.
States code are often also available in official or unofficial and annotated or unannotated versions.
Example. The Massachusetts Code is available in the following versions:
See Bluebook Table 1.3: States and the District of Columbia to identify code sources and citations for each state.
Current versions of state statutes are available online via Westlaw, Lexis, Bloomberg and state websites.
Current versions of state codes are also available in print in the Library reading room. See the section on Finding Statutes in the Library for tips on how to find them.
Historical and superseded statutes can be used to find out what the law was at a particular time in the past.
Older state statutes are available online via Westlaw, Lexis and HeinOnline. Dates of coverage vary. Generally Lexis and Westlaw coverage of historical codes starts in the late 20th century. HeinOnline coverage generally includes the earliest versions of codes, but ends in the early -mid 20th century.
Print and microfilm versions of superseded statutes are in storage. Use the table of HOLLIS & Hein Links to State Statutes linked below to locate and request them.
Looking for a print or page image version of U.S. federal or state codes for cite-checking?
Print copies of the current versions are located on the 4th floor of the Library in the reading room. The U.S. Code is located at call number KF62. Current state materials are shelved alphabetically by state starting at KFA.
You can use the HOLLIS record to locate the current item on the shelf or to initiate a request for a historical version of the statute. This spreadsheet links to HOLLIS and Heinonline versions of the statutes.
See the video below for more details on how to submit a successful request.
Statutes are most easily located by a citation to public law number, session law number or code.
U.S. Federal Laws:
See Bluebook Rule 12: Statutes
Dodd-Frank Wall Street Reform and Consumer Protection Act, Pub. L. No. 111-203, § 929-Z, 124 Stat. 1376, 1871 (2010) (codified at 15 U.S.C. § 78o) (emphasis added)
U.S. State Laws:
State law citations vary by jurisdiction. For state code citation methods, consult the Bluebook, Rule 12: Statutes and Table 1.3: States and the District of Columbia .
Databases may not recognize your citation format. These tools can help you format your citation and easily pull up a statutory section.
Statutes often have a common name such as the Dodd-Frank Act, Patriot Act or Family Medical Leave Act. You can find the statute using the name
Publishers create alphabetical tables of the popular names of statutes. The table contains session law citations and list of the sections where the law has been codified. The U.S. Code and many state statutory codes have popular name tables.
If you know the name of a law, you can also try searching online. Major federal statutes may have a Wikipedia entry with citations and links. You may also find information about a statute in news sources, government websites and Library research guides.
If you have an incomplete citation or a citation that refers to a specific subsection of a session law, and you want to find the relevant section of the code, try a classification table. Statute classification tables list correspondences between the parts of recent session laws and the places in the code where they have been incorporated.
Sometimes you will need to determine whether there is a controlling statute for a particular area of law. Before you start searching, identify the following:
jurisdiction (federal, state or multiple jurisdictions)
keywords (search terms that you will use to describe the legal question)
time period (current law or law in force at some time in the past)
Remember: not all legal issues are governed by statute!
Secondary sources are usually the most efficient way to identify whether there is a controlling statute for your question and learn more about a particular area of the law. For state law questions, look for a state legal encyclopedia, treatise or practice guide. Use earlier editions of treatises and practice guides to identify historical statutes.
Use the subject index for the code in your jurisdiction. Indexes will usually be located in the print set, or online via Westlaw. Tips for index searching:
Go back to secondary sources if you fail to find an appropriate statute.
Statutory language is often very specialized, so keyword searching can be difficult.
Tips for keyword searching:
You may be asked to compare the law on a subject in multiple jurisdictions or create a 50 state survey of the law. This can be time consuming and tedious. There are several tools and pre-compiled resources to help make this process easier. See our Research Guide to Comparing State Laws and Constitutions for details.
Before relying on a statute, you need to be sure that it hasn't been amended, repealed or overturned by a court decision since it was published.
To update a statute that you've found in print:
Other places to check:
Check the currency note at the beginning of the code or code section when looking online. Most online versions of various codes are updated within 48 hours of legislative changes.
Next, look for any changes that might have occurred after the most recent update to the online statute.
To establish the validity of a state law, use a citator like Shepard's, KeyCite or BCite to locate current cases and materials that analyze your statute.
Read the statute carefully. Does it cover the legal issue you are researching?
Browse the Table of Contents or the chapter or title outline. What other sections seem relevant?
Context is important when analyzing statutes. In particular, look for:
Use statutory annotations to deepen your understanding of the statute and to continue your research for mandatory and persuasive case law precedent.
Annotations may include:
Citators like KeyCite (West) and Shepard's (Lexis) will lead you to cases that apply and interpret the statute and secondary sources that analyze and discuss the history and application of the statute.
Use secondary sources (treatises, practice guides, law review articles, etc.) to learn more about the context, history and analysis of a particular statute or area of law.
Secondary sources are also useful for exploring the methods and theory of statutory interpretation.
Legislative history is used for discovering sources of information about legislative intent. Legislative history includes any of various materials generated in the course of creating legislation, such as reports, hearings and legislative debates.
For more details, check out our HLSL guide to Federal Legislative History
You may see references to model or uniform laws. These laws are usually developed by the Uniform Law Commission and are intended to bring "clarity and stability [in] critical areas of state statutory law."
These laws themselves are not binding, but many states have adopted them or incorporated parts of them into their codes.. A notable example is the Uniform Commercial Code.
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