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United States: IALS Library Guides

An introduction to legal research in the jurisdiction of the United States of America

United States

Guide last updated by Liz Murray, July 2018

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The United States has a common law federal legal system in which the written constitution allocates particular powers to the federal government leaving the remainder to the individual states. The federal and 50 individual state governments operate in parallel, all with their own executive, legislative and judicial branches. As a consequence there is a large body of primary law covering the federal and the state systems.

IALS has an extensive collection of US Federal primary and secondary resources in print and electronic formats and a more selective collection of State primary resources, concentrating on California, New York, Pennsylvania, Texas and Louisiana.

Legislation: Introduction

Legislation is subdivided into the Constitution, Federal and State statutes and Federal and State regulations. Statutes and regulations are published both chronologically and in codified form.

Legislation: Constitution

The Constitution, “the supreme Law of the Land”, defines the structure of government with the separation of powers between the legislative, executive and judicial branches, defines the powers of the federal government and guarantees the basic rights of US citizens, such as the right to "bear arms".

The Constitution is arranged in (roman) numbered Articles, which are subdivided into Sections and then into Clauses. An example of a citation would be: U.S CONST. Art. II, §1, cl. 7. Amendments appear separately at the end.

Electronic sources

There are numerous electronic sources and a useful list produced by the Library of Congress.

In particular it is worth noting:

The Constitution of the United States published on the US Government Printing Office site.

The Constitution as exhibited on the National Archives website

Findlaw has a copy with annotations.

The text is available on both Lexis (database ID USCS) and Westlaw (database ID USCA-CONST).  See our Westlaw and Lexis Guides for more information. It is also available on World Constitutions Illustrated (HeinOnline).

Printed sources

The main and official printed source for the U.S. Constitution is the United States Code. IALS has the annotated code at classmark GP1.E.9

It is also reproduced in:

  • Constitutions of the United States: National and State (IALS classmark GP1.C.1 CON).  Loose-leaf set published by OUP/Oceana for Columbia University.

Legislation: Federal statutes and codes

Federal statutes are published both chronologically and in codified form and are categorised (like UK ones) as Public or Private.

Federal statutes: chronological

Public laws are cited by title and date as in the UK. Since 1957, the numeric citation has been in the form Pub.L. 102-61 where 102 means it was passed by the 102nd Congress, and 61 is its number. A Congress lasts for two annual sessions. (the 102nd was from January 1993 to December 1994).

Private laws are published only in the Statutes at Large series. Citation is in the form: Priv. L. 102-29. Joint resolutions of House and Senate are numbered as Public Laws.

Example of a reference for a specific section of an Act:

National Environmental Policy Act of 1969, Pub. L. 91-190, § 102, 83 Stat. 852 (1970)

Electronic sources

The GPO site has the official version of Public and Private Laws from 104th Congress (1995-96) to date.

HeinOnline has them from 1789 to 2007.

Lexis has the Statutes at large.


Westlaw has a much shorter file of Public Laws in two parts: US-PL for the current term and US-PL-OLD for the period 1973 to (the previous term). Westlaw also has an online version of the Congressional & Administrative News mentioned above: database ID: USCCAN. (includes US-PL, US-PL-OLD for the dates mentioned, plus LH, the legislative history materials back to 1948).

Printed sources

The American term for chronological statutes is "session laws". The official series is the Statutes at large: this is in chronological order like the British Public General Acts series. It is held in the IALS basement at RES FOL GP1.E.14 up to 1942 and is also available in LSE and the British Library (from 1975). Citation is by volume and page in the form 89 Stat 213.

IALS also has the Congressional & Administrative News. Published by West from 1941 (The IALS set is complete except for 1941), shelved at GP1.E.12. It includes an extensive selection of "legislative history", i.e. House or Senate committee reports etc. produced during the passage of the Bill. Starting with 1975, the pagination conforms to that of the Statutes at Large.

Federal statutes: codes

Codification is the process by which statutes are rearranged into subject order and any subsequent amendments are incorporated. This does not mean that the U.S has a "Napoleonic code" legal system such as is found in civil law jurisdictions, although the state of Louisiana is the exception, like Quebec in Canada, in that it does have a system of private law based on the French Code Civil.

When looking for a statute in the Code, it is important to be aware that a statute could have its sections “scattered” through a number of different titles within the Code

Electronic sources

There is an official online version published by the Office of the Law Revision Counsel, but for a much more user-friendly version, see the Cornell Legal Information Institute.

Lexis has its own version called United States Code Service (USCS), which is in fact the online version of an annotated paper edition published by Michie in over 200 volumes. Use “Find Source and enter “united states code”. To reach title 42 section 4332 for example, use cite 42 & 4332 as your search.

Westlaw has the code in Database ID: USCA. (But use Find by Citation if you can).  HeinOnline has several editions of the United States Code, from 1925 to 2006.

Printed sources

The official compilation is the United States Code (official edition). The subtitle reads: "Containing the General and Permanent Laws of the United States, in force on January..." It is published every 6 years by the U.S. Government Printing Office, and updated by bound annual cumulative supplements.

It is arranged in 50 numbered (but alphabetically arranged) "Titles" covering broad subjects. For example, Title 15 is Commerce & Trade, Title 42 is Public Health & Welfare. The U.S. Constitution is included, but outside the numbered Title sequence. Within each Title the sections are numbered in a single long sequence. Citation is in the form 18 USC §1206. It should be noted that the section numbers in USC do not relate to the section numbers in the original legislation. However, the original section numbers are still the official way to cite, even though your main source for an updated version is the Code.

Example of a full reference to a specific section of an Act as currently in force: National Environmental Policy Act of 1969 § 102, 42 U.S.C. § 4332 (2000)

The IALS set of the official edition is out of date, being a mixture of the 1982 and 1988 editions / supplements), and is shelved in the closed basement. The British Library has the "2000 edition" (laws in force on January 2, 2001); it should also be at LSE as a depository library.

The IALS holds the commercially published United States Code Annotated (West) shelved at classmark GP1.E.9, but this is only up-to-date to 2010. This has a large amount of annotation including case digests and law review articles related to each section. The set was updated, until 2010, by annual pocket parts in the back of the volumes, plus quarterly pamphlets.  For citation, West Publications use the style 42 USCA § 4332.

Finding statutes: electronic

Lexis and Westlaw have online versions of the Popular Name Table. Westlaw, unlike Lexis, lets you enter a citation. Use the “Find by Citation” tab, make sure you change the country to US - United States then enter e.g. 13 usc 1300 or pl 94-123

Finding statutes: print

For statutes up to 2010, you can use the Tables volumes or General Index (if you are searching for a statute by subject) in USCA (or US Code).

For later statutes, it is best to search USCA, which is available on Westlaw.

Finding cases which refer to statutes

Use the case annotations in USCA. This is available on Westlaw, but section references might be to the US Code version, not the original Act.

Legislation: Federal regulations

Federal regulations: chronological

Federal regulations include the usual regulations made by departments of government (equivalent to British Statutory Instruments) and Presidential Proclamations and Executive Orders (approximately equivalent to Orders in Council).


Electronic sources

The Federal Register is available free on the Federal Register website.

HeinOnLine has the Federal Register in PDF format from vol.1 (1936) onwards.

Lexis has it from 1980 onwards. Use Find Source and enter federal register.

The Westlaw Database ID is  FR with a start date also 1980.

Print sources

The official printed source is the Federal Register 1936- . This is not held in IALS but is in the British Library and LSE Library. Regulations are also printed in the Congressional and Administrative News which is in IALS and shelved at GP1.E.12.

Federal regulations: codes

Electronic sources

The Code of Federal Regulations is on the GPO Access website at and at the Cornell Legal Information Institute website.

It is on HeinOnline for the years 1938 - 2010.

On Lexis, use Find Source and enter federal regulations

On Westlaw the Database ID is CFR. The numbering is tricky, so a “Find by Citation search may fail.

Print sources

The Code of Federal Regulations is not held in IALS, but is held in the British Library and LSE Library.

Electronic sources

The Code of Federal Regulations is on the GPO Access website at and at the Cornell Legal Information Institute website.

It is on HeinOnline for the years 1938 - 2010.

On Lexis, use Find Source and enter federal regulations

On Westlaw the Database ID is CFR. The numbering is tricky, so a “Find by Citation search may fail.

Non-codified acts

Some Acts are not codified at all. If the Act dates from before Congressional & Administrative News (start date 1941, IALS copy 1942), use Statutes at Large.

Legislation: State statutes

State statutes

These follow a similar publication pattern to federal statutes: in practice codified versions are normally used in preference to session laws.


Electronic sources


There is a list of free internet sources on Findlaw and on the Cornell LII.


Lexis and Westlaw also have this material.

Print sources

IALS currently subscribes to the codes (not session laws) from Louisiana (civil, civil procedure, criminal procedure).

Legislation: Uniform laws

These are State (not Federal) laws, which may or may not be adopted by individual states, and are intended to achieve some form of uniformity without surrendering sovereignty. Uniform laws are devised by the National Conference of Commissioners on Uniform State Laws, which was set up in 1912. The prime example is the Uniform Commercial Code.

Sources of Uniform laws

The main printed source is the set of volumes titled Uniform Laws Annotated (West Publishing).  IALS holds these at GP1.E.8. It contains all the uniform laws which have been adopted by at least one state and includes references to variations in individual states. Uniform laws are also incorporated in a state's own statutes.

Lexis contains the Martindale-Hubbell uniform and model acts which offer a selection of uniform laws and parts of the Uniform commercial code.

Westlaw Database ID: ULA.

Law reports: Introduction

There are both Federal and State courts and it depends on field of law as to which have jurisdiction. Note that Federal Courts do not sit just in Washington DC, there are Federal Courts in the states as well.

Conflict of laws is an important issue in the US involving matters such as the choice of law as between states, choice of forum etc.

The citation style is the same as in the UK, except that the date is usually given at the end: 496 US 226 (1990).

Law reports: Federal

The main federal courts of general jurisdiction are the US Supreme Court, the US Courts of Appeals (in 12 regional circuits plus 1 Federal) and the US District Courts (in 94 judicial districts).

(a) Supreme Court cases

Electronic sources

The official Supreme Court website has PDF versions of decisions starting with vol. 502 U.S (October 1991 term).

The U.S. Department of Commerce website, Fedworld, has ASCII versions of Supreme Court decisions from 1937 to 1975.

Heinonline has a PDF archive of the US Reports from 1754 (vol.1) to 2006 (vol.548).

Lexis has the L.Ed. version from 1790 onwards. Use Find Source and search on supreme court. Select  "U.S. Supreme Court Cases, Lawyers' Edition" from the list, avoiding the sub-sets.

On Westlaw, as with statutes, you can find a case directly by its citation, or if searching by terms use the file name SCT for cases after 1944, and SCT-OLD for cases between 1790 and 1945.

Print sources

Supreme Court cases are published in three printed series of which IALS holds one:

  • The United States Reports, the official Government Printer series. They are cited as US (e.g. 295 US 123). This official series is not held in IALS but it is in LSE.
  • Supreme Court Reporter; part of West's National Reporter System and cited as S.Ct. This is not held in IALS.
  • United States Supreme Court Reports. Lawyers' Edition (L.Ed), published by LN/Matthew Bender). This includes annotations similar to periodical articles. It is held in IALS at classmark GP1.G.2 and the subscription includes advance issues as well as bound volumes. It is now in its 2nd series, cited as L.Ed. 2d.

Note: the volume and page numbering for the L.Ed. version is not the same as the official U.S. but the US numbering appears on the spine of the L.Ed. volumes in smaller print.

Until 1874 it was usual to cite by the name of the reporter (similar to the UK nominate reports), but then "US" volume numbers were assigned retrospectively, so that e.g. 12 Wheat. = 25 US, and 23 Wall. = 90 US.

(b)   Lower Federal Courts

(i)  Court of Appeals cases

Court of Appeals decisions are in the Federal Reporter shelved in IALS at GP1.G.12 (some of it is in the basement with classmark prefix RES). They are cited F (or F 2d, or F 3d for the second and third series).

(ii)  District courts

District Court decisions were published in the Federal Reporter up to 1932 and are now in the Federal Supplement at GP1.G.7. (Some of it is in the basement with classmark prefix RES). They are cited F. Supp. (or F. Supp. 2d for second series). There are several Federal Districts in each State.

Electronic sources

Both Findlaw and The National Center for State Courts list court web sites for each state where selected cases are provided. They are also available on both Lexis and Westlaw.

Law reports: State

States have their own hierarchy of courts with a Supreme Court at the top. Most states have their own official or commercial series of reports.. West publishes a number of regional law report series which groups the reports from several states and these report the highest court decisions from each state in that region. Start dates are all in the 1880s and each is now in at least a second series.

Citations for state reports not held in IALS can be translated into citations to the various National reporter series which are in IALS using the National Reporter bluebooks. These are shelved at GP1.G.114.

Electronic sources

The National Center for State Courts and Findlaw both list court web sites for each state where selected cases are provided. They are also available on both Lexis and Westlaw.

Print sources

IALS does not currently subscribe to any of the individual state series in print (it does hold some old series), but the Library has all the regional units of West's National Reporter System: Atlantic, North Eastern, North Western, Pacific, South Eastern, Southern, and South Western Reporter, up to early 2008.   All first series and the first 100 volumes of each second series are in the offsite store or in the basement. California Reporter from 1959 onwards and now in its 3rd series (at IALS classmark GP5.G.2) and New York Supplement now in its 2nd series (at IALS classmark GP31.G.7) include some lower court decisions not reported in the Pacific and North Eastern reporters respectively.

Law reports: Notes on reports held at IALS

American law reports annotated

This is an important series of law reports which is often regarded as a journal. It has been published since 1919 and is shelved in IALS at classmark GP1.G.10 for the 3rd to 5th series. The first and second series are in the basement with classmark prefix RES. It contains selective reports of appellate cases, but its most important feature is that it also contains lengthy encyclopaedic essays or "annotations". The series is often cited in the literature for these annotations. From the 5th series onwards, the case reports are at the end of the volume after the annotations, and form a quite small proportion of the content.

Since 1969, federal appellate cases have been published in ALR Federal shelved at IALS classmark GP1.G.34. All the ALR series have their own indexes and updating volumes.

The ALR database on Westlaw contains only the annotations, not the cases.

Currency of print US law reports at IALS

With the exception of the Supreme Court reports, IALS does not subscribe to the preliminary paper parts containing the most recent cases. In addition all bound volumes are shipped by surface mail. Therefore IALS print holdings will not contain very recent cases. For the Supreme Court decisions, IALS receives the advance paper parts and interim bound volumes as well as the permanent bound volumes which are about 5 years behind in publication. Until 2009 IALS subscribed to US law week which provides information on new cases. Otherwise it is necessary to use electronic sources. The Supreme Court website has recent slip opinions. Academic users can use Lexis+ or Westlaw.

Digests and citators


IALS no longer currently subscribes to any major US "narrative" encyclopaedic digests (like Halsbury's Laws) in print. It holds historic sets of:

  • Corpus Juris Secundum. (up to 2007) Shelved at GP1.H.2. Comprises 100 plus volumes. This is available on Westlaw Database ID: CJS.
  • American Jurisprudence 2d. (up to1993) Shelved in the basement at RES GP1.H.15. This is available on Westlaw Database ID: AMJUR
  • West's General Digest, (up to 1986). This is the rough equivalent of UK's The Digest. It cumulates into Decennial Digests and is shelved in the basement at RES GP1.H.4. The latest of these in IALS was so huge it was issued in two parts: 1976-1981 (38 volumes) and 1981-1986 (48 volumes).


The two main tools for US citation analysis are Shepards Citations and Keycite and the generic name for the process is often known as “Shepardizing”. The system is completely different from the British equivalent and consists of numerical tables arranged by source citation. As an example: if you have a case reported at 263 S E 2d 391, you look up that citation in the Shepards South Eastern Reporter Citations volume and find a column of the citations for cases which have considered your case. Various superscript codes indicate what treatment was given by the citing case (followed, distinguished etc.)

IALS only holds historic print sets up to 1994 relating to the law report series we subscribe to.

Westlaw has its own system called Keycite. When viewing a case on Westlaw, click on the Keycite function to see the full history.

Encyclopaedias, dictionaries & form books


The closest to the British style "Encyclopaedia of... law" (i.e. a mixture of statutes, cases, official circulars etc.) are probably the CCH "Reporters" which are published commercially in looseleaf. IALS has a few of these, notably

Federal Securities Law Reporter shelved at classmark GP1.G.43

Federal Banking Law Reporter shelved at classmark GP1.G.44


Black's Law Dictionary 9th ed., 2009. Shelved at RF72 BLA is a one-volume standard work.

Fox, E.H. The Legal research dictionary: from advance sheets to pocket parts 2nd ed. 2006. (Useful for brief definitions of types of publications).

Words & Phrases 1658 to date (at GP1.H.16) "All judicial constructions and definitions of words and phrases by the state and federal courts from the earliest times, alphabetically arranged and indexed". Over 90 volumes!

Form books

IALS subscribes to West's Legal Forms shelved at SJ350 WES

Restatement & model codes

These are a "An attempt made by the American Law Institute to have formulated in propositions, rather like the articles of a code, what are deemed to be the best doctrines and principles of the main branches of the law of the U.S., particularly the branches still mainly dependent on case-law". (Walker, D.M. The Oxford Companion to Law, 1980)

The restatements are prepared by academics, judges and practitioners in a variety of subjects including agency, contracts, foreign relations law, restitution, torts, trusts and conflict of laws. Many are in 2d or even 3d editions. They contain rules and commentary and are referred to by the courts, so probably count as "persuasive authority".

IALS has a complete set in print and they are all available on Westlaw.


IALS holds some print bibliographies:

  • Bibliographic guide to law 1969 to 2003 (IALS classmark BB20.J.5) published by G.K. Hall and compiled electronically from annual Library of Congress law acquisitions
  • Law books 1876-1981 (IALS classmark BB20 LAW) Bowker. 4 volumes provides an historical list.

The major US university law library catalogues can be a useful source of current information e.g. Columbia, Harvard, Yale, New York University.

The literature is too vast to collect everything particularly with material on both Federal and state law available. In general, IALS tries to stock at least one major work in the main subject areas. Many are multi-volume works in looseleaf or are updated annually with pocket parts. e.g.:

  • Appleman on Insurance
  • Benedict on Admiralty
  • Grad on Environmental law
  • Nimmer on Copyright
  • Scott on Trusts
  • Wigmore on Evidence
  • Williston on Contracts

Most deal primarily with Federal law but IALS does collect some important state material e.g. Balotti & Finkelstein The Delaware law of corporations and business.

Government publications

Details of publications from 1976 onwards are available on the U.S. Government Printing Office website at For older material, there is the Monthly catalog of US government publications. IALS has 1967-83 in paper and 1984-95 on microfiches.

IALS has very few US government publications. The LSE Library, which is a depository library for US government publications, should hold a complete set.


The IALS Library has a very extensive, though not comprehensive, collection of American law reviews, comprising over 500 titles. Generally speaking IALS does not subscribe to titles aimed purely at the practitioner such as newsletters issued by the various sections of the American Bar Association. Some titles, or early volumes in a title, may be shelved in the offsite store or in the closed basement. For details consult the online catalogue.

Many titles, including those published by the American Bar Association are available electronically in HeinOnline, Lexis and Westlaw.

Periodical indexes

IALS holds or provides access to several major journal indexing services

Print sources

  •  Index to Legal Periodicals is held in print from 1909 to 1981 shelved at BB55.J.1
  • Current Law Index is held at IALS held in print only from 1980 and shelved at classmark BB55.J.12. This index has the backing of the American Association of Law Libraries. (IALS does not currently subscribe to the online version Legaltrac).

Electronic sources

Index to Legal Periodicals is available electronically from 1981.

Lexis contains Index to Legal Periodicals. Use Find Source and enter Index to legal periodicals.

On Westlaw, the easiest access is direct by database ID: either ILP or LRI.


Martindale-Hubbell Law Directory. This is produced annually and is considered the main source although it does not have any official status and lawyers pay to get an entry. IALS does not have a current print subscription but the main directory information is available free on the Martindale-Hubbell Law Directory website. The web version does not include the very useful foreign law digests, which are part of the printed set.

How to cite US resources

There are 2 main guides:

The Bluebook: a uniform system of citation. 19th ed., 2010
It is compiled by the editors of the Columbia Law Review, the Harvard Law Review, the University of Pennsylvania Law Review, and the Yale Law Journal. It has updates and corrections on its website. In addition it includes a table of states with lists of law reports & laws for the US and foreign jurisdictions.

The ALWD citation manual. 3rd edition, 2006 (IALS has the 2000 edition).

The Association of Legal Writing Directors manual was produced as an alternative to the Bluebook. The appendices are freely available on the web and appendix no. 1 lists print sources for each state.


Research guides

Lomio, J & Spang-Hanssen, H Legal research methods in the US and Europe, DJOF Publishing, 2009

Mersky, R & Dunn, D Fundamentals of legal research, 9th ed. Foundation Press, 2009

Neacsu, D Introduction to US law and legal research, Transnational Publishers, c2005

Hall, K Oxford companion to American law, OUP, 2002

Free electronic sources of US law

GPO access




Hieros Gamos

Eagle-i Internet Portal for Law

Notes on Lexis and Westlaw

These 2 subscription databases are only available at IALS to academic researchers. For information about who can access these databases and how, see the IALS Law Databases.

Both Lexis+ and Westlaw UK provide access to U.S. materials for UK users, but both launch with a British based front screen and you must select the appropriate part to access the international resources.

In Lexis+, click on the Sources tab, choose Browse Sources, and then select United States from the country filter.

In Westlaw, to select Federal, click Services on the toolbar, then click Westlaw International, and select US Federal. For state materials either use the “law school classic” tab or click on “Directory” at the top of the screen then select “All Westlaw databases”. Westlaw provides a very useful “Find by Citation” function which works on the U.S. primary sources, though not so well on the journals.