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Statutes: US and State Codes


Guide Overview

This guide is designed to help you understand and find statutes (codes or acts).

For a detailed guide to U.S. federal legislative materials, check out this HLS guide to Federal Legislative History:

Statutes are laws enacted by legislatures, such as the US Congress.  Statutes are typically the place to begin research of primary legal sources.  Subject only to constitutional control, they authorize promulgation of administrative regulations and can overturn or modify court decisions that themselves are sometimes concerned with statutory interpretation. 

In the US, both the federal government and individual states have the power to pass statutes or laws. Some laws are handled exclusively by the federal government or Congress, while others are handled exclusively by the states.  Still other laws are the subject of both state and federal governance.

Creating Statutes

Statutory Documents

Statutes are often referred to as codes or acts, and even just "law."  They are published in three intervals:

  1. Slip laws

  2. Session laws

  3. Codes

Slip Laws

Statutes are published in slip form soon after being enacted.  Slip laws are the first to be printed or appear online after enactment, and are used to find the latest legislation.

Slip laws provide information in the headings and margin notes about enactment dates.  They reference the place where the law will be codified, for example, in the United States Code (U.S.C.).  At the end of the slip law, there is often useful information on legislative history materials, such as Senate or House reports. 

Slip laws may be cited by a public law number, which incorporates the number of the enacting legislative session and the chronological number of the bill in that session.

Session Laws

Session laws are all the slip laws enacted in a legislative session arranged chronologically by enactment date. Session laws contain the complete text of laws exactly as they are enacted.  They are the most authoritative form of the law, and control when there are differences in wording from a session law to a final published code. Session laws are used in historical research and in compiling legislative histories.

Statutes at Large are the official source the session laws of Congress; these session laws include reference to a public law number.


Codes provide the most complete picture of the law at a particular time, and are used to find the current legislation in a particular jurisdiction. Codes bring together related statutes and incorporate amendments into the text of existing statutes.  They are arranged by individual subjects called titles.  Code volumes usually contain references to the session law that have been incorporated in a particular code section.

When conducting research, it is advisable to use an annotated code.  Annotated codes cross-reference other relevant statutes, regulations, cases, legislative documents and secondary sources.

Sample Citation [Bluebook R. 12.4]

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)

Finding Slip Laws & Session Laws

Federal Bills

Federal Session Laws (Statutes at Large)

State Slip Laws & Session Laws

Federal Statutes

The United States Code

There are three editions of the United States Code: 

  1. The United States Code (U.S.C.)
  2. United States Code Annotated (U.S.C.A.) (Westlaw)
  3. United States Code Service (U.S.C.S.) (Lexis)

The U.S.C. is the official code of the United States, and is published (in print) every six years with annual cumulative supplements.  The U.S.C. is divided into fifty-one major topics called titles.

The Government Printing Office (GPO) print version of the U.S. Code remains the final authoritative version.  This code is also available online at GPO. Note that Heinonline has digital copies of the historical U.S.C. starting in 1926, and earlier.

The U.S.C. contains only the text of the statute.  For research, it is advisable to use an annotated code, such as the U.S.C.A. and U.S.C.S. 

Annotated codes contain the statute language and make reference to other helpful primary and secondary sources.  They provide citations (and links) to cases applying the statute.  They cross-reference other relevant statutes, regulations and legislative documents; and link to practice guides, treatises and law review articles that discuss the statute. 

You can search by citation, index, or popular name in Lexis, Westlaw and Bloomberg Law.  Statutes are also searchable and findable online through Google-Wikipedia or other sources.  

Sample Citation [Bluebook 12 and T1]

7 U.S.C. § 1b (2006)

Getting the US Code


  1. GPO (1994 - ) (free)
  2. Heinonline (1925- )
  3. Westlaw (annotated)
  4. LexisNexis (annotated)
  5. Bloomberg Law
  6. Legal Information Inst. (free)


HLS Library reading room and in the reference room [KF62]

State Statutes

State Codes

Most states publish their statutes in a manner similar to the federal government. For example, most states publish their statutes initially in a slip law format, and have official publications of the session laws.  

Also like the federal government, states may have different versions of the code. For example, the Massachusetts code is unpublished in three versions:

  1. General Laws of Massachusetts (Official)
  2. Massachusetts General Laws Annotated (Westlaw)
  3. Annotated Laws of Massachusetts (Lexis)

States can be as unique as snowflakes. Thus, even if the legislative process is similar to the federal one, the language used to describe statutes and the statute language itself may vary widely.  In addition, not all states maintain current official codes.  The Bluebook provides details on state statutes in Table 1.

Note that HeinOnline has digital copies of historical state statutes.  Dates vary by state, and reach back as far as 1775 for original colony states.

When researching similar laws in more than one state, such as child support laws, consult compilations of state laws.  Check out this guide on Comparing State Laws.

Locating Statutes at HLSL

Looking for a print or page image version of U.S. Federal or State Statutes? This spreadsheet links to HOLLIS and Heinonline. 

Use the HOLLIS record to locate the item on the shelf or to initiate a Scan & Deliver request from the correct version of the statute. 

See the video below for more details on how to submit a successful request. 

Requesting Scans of State Statutes for Cite Checking

Finding Codes

Finding Codes by Citation

Code Citations

Statutes are most easily located by citation, whether to public law number, session law number or the United States Code.

For a session law of Congress the official source is the Statutes at Large, the citation format for which is: Volume no. Stat. Page no., e.g., 104 Stat. 327.

An official citation to a Congressional session law also includes a public law number specifying its place in the chronological order of passage among the statutes of the Congress that enacted it, e.g., Pub. L. No. 101-336 - the 336th Public Law enacted by the 101st Congress.

United States Code citations (to whatever source - U.S.C., U.S.C.A. or U.S.C.S.) are specified by title, abbreviated code name and section number; e.g., 20 U.S.C. 1080 is a citation to Title 20 (Education), § 1080 of the official U.S. Code.

For state code citation methods, consult Table 1 of the Bluebook.

Sample Citation

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) [Bluebook R. 12.4]

Statute Classification Tables

Sometimes search for a particular statute begins with an incomplete citation or a specific section or other subdivision of a law that could be a reference to a part of that statute either in terms of its slip and session law divisional organization or in terms of the location in the code in which it has been classified by subject.

Statute classification tables list in session law citation order and section-by-section sequence correspondences between the parts of a session law and the places in the code where they have been incorporated, either as new sections or as amendments to existing ones.

For the federal code, use the U.S. Code Classification Tables.

Finding Codes without a Citation

Getting Started without a Citation

Ask yourself the following:

  1.     Jurisdiction (federal or state)
  2.     Keywords (search terms that you will use to describe the legal question)
  3.     Time period (current law or law in force at some time in the past)


Statutes are often referred to by common names such as the Patriot Act or Family Medical Leave Act.  A quick way to find a citation to a well known statute is to use Google-Wikipedia.  Wikipedia entries often contain citation to both the public law number and U.S.C., and offer links to and GPO (government sources for statutory docs).

Popular Name Tables

Government and commercial publishers of the U.S. Code have alphabetically arranged popular name tables. Popular names are generally based on an official name designation at the very beginning of a slip law, typically a "short title" that is part of the full citation to an individual statute. Each name is followed by Public Law and Statutes at Large citations and at least a partial list of the Code titles and sections to which the statute has been classified. 

Secondary Sources

Use secondary sources (treatises, practice guides, law review articles, etc.) to learn more about the law governed by a particular statute or to learn more about the statute itself. Here's a guide for finding treatises.

Subject Indexes

Use the subject index for the code in your jurisdiction.  Indexes are found at the end of the print set; most indexes are multi-volume (even online).  Westlaw contains indexes for the U.S. Code and for state statutes. LexisNexis does not.

When using an index, start with specific terms and proceed to more general terms.  Use synonyms and alternative expressions (for example, "insolvency" as well as "bankruptcy").  Be creative and persistent but remember: not all legal issues are governed by statute. Go back to secondary sources if you fail to find an appropriate statute.

Keyword Search

Most statutes are easily findable online; on the the left of this page are links to federal and state resources for statutes.  When keyword searching, try to anticipate the language used by the legislature in writing the law.  It may be useful to start with a Wikipedia entry that discusses a particular legal topic to get key search terms.  You may also want to search the index (if available) to get synonyms for key terms - and citations to potentially relevant statutes.

Updating Codes

Updating Codes Online

The U.S. Code is often updated within 48 hours online

State Slip Laws

State Session Laws

Updating Codes

Updating Online

Most online versions of various codes are updated within 48 hours of legislative changes. Check the currency note at the beginning of the code or code section when looking online - such as in Lexis, Westlaw, Bloomberg Law, GPO or at a state's legislative website.

The U.S. Code Classification Tables are useful for identifying very recent additions and amendments to the U.S. Code.  These tables are sorted in U.S. Code order as well as by public law number.

For recently enacted federal legislation in slip law or otherwise, visit THOMAS. Thomas can be word/phrase (or index) searched by date for proposed additions or amendments to the U.S. Code. Congressional bills are also word/phrase searchable at GPO.

State legislative sites offer bills in full text and commonly provide keyword searching and bill status information.  In addition, commercial databases such as Westlaw, Lexis and LexisNexis State Capital provide state session law searching for state code updates.

Updating in Print

Check the pocket part in the back of the volume or the cumulative supplement. These supplements are usually published annually.  Look for legislative service pamphlets. These updates are published throughout the year and usually include a cumulative list of statutes affected by recently enacted laws and a cumulative subject index.

Tables of amendments and repeals published in codes and advance legislative services provide citations to session laws that modify existing statutes.  All three versions of the U.S. Code and Statutes at Large through 1976 contain tables of amendments, repeals and new code provisions.

Validating Codes

To establish the current validity of an existing statute, find and read case law (in your jurisdiction) that cites your statute.  Look out for court constitutionality rulings and other holdings affecting the statute's "good law" status.

If you are looking at a statute in a commercial database like Lexis, Westlaw or Bloomberg Law, then you can use a citator (like Shepard's or Key Cite) to locate current materials that analyze your statute, such as cases and secondary sources.

Analyzing Codes

Read & Browse

Read the statute carefully. Does it indeed cover the legal issue you are researching?

Browse the Table of Contents or the chapter or title outline to see what other sections may also be pertinent.  Context is important when analyzing statutes.  In particular, look for:

  • Purpose/Legislative findings: These can help you understand why the legislature enacted the law.
  • Definitions: Those definitions of words or phrases used in a law may vary from commonly accepted definitions.
  • Exceptions: Exceptions to a general law are sometimes found in their own section

Review Annotations

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:

  • Statutory History: When the statute was originally enacted and subsequently amended
  • Analysis: Links and citations to selected helpful secondary sources such as treatises, ALRs,law reviews and other materials that focus on the statute
  • Interpretation: References to important court decisions that have applied or interpreted the statute 

Check Citators

Use a citator like Shepard's or Key Cite, available in commercial databases like Westlaw, Lexis and BloombergLaw,  to locate other materials that cite your statute.  This includes citations to cases and secondary sources that discuss the history and application of the statutory language.

Dig Deeper with Secondary Sources

Use secondary sources (treatises, practice guides, law review articles, etc.) to learn more about the law governed by a particular statute or to learn more about the statute itself.

Trace the Legislative History

Legislative history is used for discovering sources of information about the legislative intent.  Legislative history includes any of various materials generated in the course of creating legislation, such as reports, hearings and legislative debates.  For a detailed guide to federal legislative materials, check out our HLSL guide to Federal Legislative History

Uniform Laws

Uniform Laws

In addition to the state codes, there are a variety of unofficial uniform laws.  These laws are developed by the National Conference of Commissioners on Uniform State Laws (NCUSL), a non-governmental body formed in 1892 upon the recommendation of the American Bar Association for the purpose of promoting "uniformity in state laws on all subjects where uniformity is deemed desirable and practicable."

The Commissioners have approved more than two hundred uniform laws, of which more than 100 have been adopted by at least one state. A few have been widely adopted. A notable example is the Uniform Commercial Code.

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