Pathfinder Repository

United States Law

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Basic Online Research

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Research in the law of the United States can be very complicated. Even most lawyers are familiar with the specialized sources in only a handful of legal practice areas. This pathfinder is intended to help members of the general public learn where to find the basic, major, sources of law and to find books and web-sites that can help explain the basics of the legal system.

Law is complicated in that it can come from many different sources. There are a number of different branches of government that can make “law”, in the American legal system (and most others!), and there are also overlapping areas of authority between the states and the federal government. When you begin to research a legal problem, one of your first questions will be whether the relevant law will come from the federal government, from a state government, or from both. A complicated set of rules relate to jurisdiction, or the determination first of what law applies (state or federal, and which state) and secondly of what court system will be able to hear the case and apply the law. There is also a distincton between substantive law – the legal rules and requirements governing behavior in the “real world” that may then lead to legal disputes – and procedural law, which is the law governing how disputes can proceed through the courts and what steps are allowed to each party in making its case.

The general public most often thinks of law as the laws, or statutes, passed by legislatures – namely the U.S. and state Congresses. Many people also recall that the United States Constitution and the constitutions of the states are law. But in the American legal system law also is made by courts, which develop new legal rules while they interpret constitutions and statutes and also general legal principles known as common law. Also, administrative regulations function very much like law. Administrative agencies, operating under the executive branches of each state or federal government, are often given power (authorized by the statutes passed by the legislatures) to flesh out those statutes by making more specific rules that the members of the legislative branch might not have the time or expertise to deal with themselves.

While I will mention print sources, I will focus on sources available freely online. I will also largely ignore the many sources that are available “online” but only through vended or proprietary subscription services (e.g. Lexis and Westlaw), rather than through Web sites. These are outside of the scope of this pathfinder because they are extremely specialized and expensive, and almost never available to members of the general public, or even to lawyers representing less well-financed clients.

The legal web-zine LLRX.com also has an article discussing the sources of law in the American legal system, aimed to researchers from other countries and focusing on Web sources, in its “foreign law” section. See http://www.llrx.com/features/us_fed.htm


Secondary Sources:
Because of the complexity of the legal system, it can be easiest and most productive to begin researching with secondary sources. These are works, like a law professor’s book or a legal-advice web site, that are not law themselves but that can help explain what the law means (or, at least, what the author thinks that it means). Some secondary sources, like treatises (major books on legal topics) or articles published in scholarly law-journals, are especially useful because they will include many footnote citations to statutes, cases, and the other actual law on a topic, and will at least attempt to explain the connections between those sources. It is important to keep in mind that, while some are very highly regarded by the courts, no secondary source counts as law itself.

Primary Sources:

Secondary sources can answer many basic law questions, can satisfy general curiosity, and can usually help point you to at least some primary materials. But at some point you may need to actually look directly to the primary law sources themselves. Unlike many of the most reputable secondary sources, recent primary sources for most jurisdictions are available online, at least in some form. Unfortunately, the versions of these sources that are freely available online tend not to be the most easily searched or researched. You may be unable, especially for specific or complex areas of law with a lot of their own sources, to do most of your research online. And historical primary materials – especially old court cases that are still law – are unlikely to be available on the Internet. Freely available online sources, however, are increasingly very useful for retrieving known items of primary law, e.g. where you have a citation to a document.

Secondary Sources include:

Online Research Guides: One way to begin – especially to find out what particular sources are important to your specific legal topic – is with more specialized research guides or pathfinders. Many law school libraries compile these (/ref/QUE/PF/lawpath2.html), for their students and other patrons, and a good number of them are available online. A search with a search engine like Google for your topic may turn up some pathfinders. Remember to use a fairly broad topic (e.g. “Tax Research Pathfinder” or “Intellectual Property Research Pathfinder” – including the words “research” and “pathfinder” in your search should also help narrow your results to appropriate sources). You are searching for guides to research, not an answer to a specific legal question — something you are extremely unlikely to find through a search engine. Look especially for sources from university-affiliated law libraries (which will have “.edu” addresses). This way, you will know that they are not from anyone who is trying to sell you legal advice that he/she/it is not qualified to give, or from a recklessly biased or non-credible source.

Click here for some additional pathfinder-type sources.(/ref/QUE/PF/lawpath2.html)

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Books: Good books on legal topics range from scholarly treatises, to practical guidebooks for attorneys, to accessible works for a general audience. An academic law library is likely to have the first and third type. A public library will have many of the third type, and may have some of the first two. The research branch of a major public library system, or any public law library, will likely have many guidebooks written for practicing attorneys. The NoLo Press (http://www.nolo.com/) publishes one series of books on legal topics, written for a lay reader dealing with legal problems. There are many books, from popular and academic presses, dealing with legal topics in a general, rather than a practical, way. (e.g. from historical or journalistic perspectives) For these, in a mid-sized general library (i.e. not in a law library where all the books are about law, or a huge academic research library) you might want to begin by searching under “subject” for “law — united states.” Depending on the size of your library and the computer system used for the library catalog, you will probably see a list of sub-topics to choose from. Ask your local librarian if you need assistance.

Additionally, two major treatises on the process of legal research, focused especially on American law, merit special mention:

Cohen, Morris L., Robert C. Berring and Kent C. Olson. How to Find the Law. 9th ed. (West, 1989).

Jacobstein, J. Myron, Roy M. Mersky and Donald J. Dunn. Fundamentals of Legal Research. 7th ed. (Foundation Press, 1998).

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Journal Articles: Journal articles can be an especially useful kind of secondary source for finding statutes and cases. These law journals are scholarly publications, usually produced at a law school and edited by upper-level students. Law professors write many of the articles. The authors of law journal articles usually are arguing that the law should be interpreted or developed in a certain way, so it is important to keep in mind that they are not just neutrally reporting. But the editorial standards of the journals require that they make their argument while thoroughly citing authoritative law (teams of law students actually do check every single footnote!), so finding a law review article on a topic you are interested in and then looking at the sources mentioned in its footnotes can be an excellent way to get a start on your legal research.

Until very recently only a tiny handful of law reviews published on the Web, however. Usually, you will need to go to a law library or to a large general academic or public library to look at law journals. The number of University-affiliated law reviews that either publish full-text online or at least make their tables of contents available on web pages is growing very rapidly, however. The Law Library of Congress has a very helpful page listing and linking to “electronic law journals and other periodically issued publications that provide substantial amounts of legal analysis” at http://www.loc.gov/law/guide/lawreviews.html. A search engine like Google, using the keyword phrases “law review” or “law journal” may turn up additional law review home pages that can be browsed for general information.

For comprehensive searching of the journal literature on a particular topic, however, you will probably need to use a professional index.

Journal Indexes: When libraries catalog serials (journals, magazines) they do not make a record for each article. There are a number of indexes to articles in serials, however. You may be familiar with the Readers Guide to Periodical Literature, which covers popular or general-interest magazines. There are also journal indexes that specifically cover legal periodicals. These include the Index to Legal Periodicals and Books and the Current Law Index (called LegalTrac in its electronic form). These publications are likely to be available in a law library, or possibly in a large academic or public library. They exist in online forms, but only as networked resources to which libraries may subscribe. Check at your local library.

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Dictionaries and Encyclopedias: There are several popular law dictionaries. The most popular is Black’s Law Dictionary, which can be found in many law and other libraries. No law dictionary is “official” and, as with all secondary sources, nothing included in the dictionary definitions is to be treated as “law” — but Black’s is probably overall the most reputable and respected of the dictionaries. The NoLo Press, publishers of law books for the lay reader, has a sort of online law dictionary that may also be useful in the early stages of research or for basic concepts, at http://www.nolo.com/lawcenter/dictionary/wordindex.cfm

There are two major sets of legal encyclopedias, American Jurisprudence (called “AmJur” and now in its second series) and the Corpus Juris Secundum (called “CJS”) that will be present in almost all law libraries and some large public and university libraries. AmJur and CJS cover the law generally, rather than being specific to any one jurisdiction. They are most useful as a starting point and introduction to the general legal setting of a particular topical area. One of their most useful qualities is that, in addition to descriptive encyclopedia-style articles, they contain many citations to case law and statutes on the topic. There are also legal encyclopedias specific to certain jurisdictions — ask a law librarian about these. The NoLo Press web page also offers a legal “encyclopedia”, much simplified and designed for the lay person, http://www.nolo.com/lawcenter/ency/index.cfm. A different approach to providing an online legal encyclopedia is offered by the Cornell Law Library, with a page offering encylopedia-style access to a variety of topical legal research guides, along with short descriptions of legal topics and issues. This source should prove very useful, and quite credible.

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Primary Sources Include:


An online edition of the United States Constitution, with explanatory commentary and history prepared by the Library of Congress for the Senate, can be found through the Government Printing Office at http://www.access.gpo.gov/congress/senate/constitution/index.html (or follow links from the GPO Access home page). The same text and commentary, in a different online format, can be found through the FindLaw web portal, as well, at http://www.findlaw.com/casecode/constitution/.
The National Archives Administration also has a page that includes photographic images of the original manuscript of the Constitution as well as an html transcription of its text, at http://www.archives.gov/exhibit_hall/charters_of_freedom/constitution/constitution.html.
Cornell’s Legal Information Insitute has a page devoted to the basics of Constitutional Law at http://www.law.cornell.edu/topics/constitutional.html and the University of Chicago also has a nice pathfinder for Constitutional Law at http://www.lib.uchicago.edu/~llou/conlaw.html. In addition to United States constitutional sources, this pathfinder discusses foreign and comparative constitutional law.

Links to state constitutions (and statutes), are collected by the Legal Information Institute at http://www.law.cornell.edu/statutes.html.

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Whether in paper or on the Internet, it is often easier to find statutory sources than case law sources. This is because statutes come from fewer different actors (there is only one legislature in each state, after all) and are usually published in a codified, or subject-ordered, form, as well as in chronological order as they are passed (session laws). The codes, or subject-ordered compilations of statutes, are usually indexed by descriptive word. Sometimes there are also tools such as the “popular name table” in the U.S. Code Annotated, that enables you to find statutory law alphabetically by its popular, descriptive, nickname (e.g. the ‘Social Security Act’). Statutes of general application are first published (and sometimes most authoritative) in the form they are passed by the legislature, as ‘public laws’ or ‘public acts’ or the equivalent. Most codifications also include with each code section a note citing the individual public act(s) or public law(s) from which that topically-ordered section originated.

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Online sources for federal statutes:

Codes: United States federal statutory sources are available online in several forms. Begin with http://www.access.gpo.gov. This is the homepage of the Government Printing Office, the official printer of the federal government. Follow the link labelled “GPO Access” on that page to access a wide range of official federal government sources. For statutes, click the link under “Legislative” (in the left column) or else go directly to the U.S. Code (right column). You will have the option of keyword searching the code or browsing by title and chapter. Both methods have drawbacks compared to the flexibility of the print editions — with keyword searching you will have to correctly guess the wording used in the code section you want and the browsing option does not map chapter titles to their included section numbers — but the U.S. Code is fully available online (check carefully for the date through which the code is current, however, you may also need to search public laws for more recent changes).

The U.S. Code is also available from the Cornell’s Legal Information Institute. In this form, sections can be accessed by citation (title and section number) and code titles can be searched individually: http://www4.law.cornell.edu/uscode/

Unfortunately, the very helpful commercially-published annotated editions of the U.S. Code are not available to the public online. These editions, the United States Code Annotated and the United States Code Service are very useful to the researcher because they include, following each section of the code, citations to and descriptions of case law and other useful cross-references. They also are updated in a way that makes them somewhat easier to use than the print or online versions of the GPO edition of the U.S. Code.

Session Laws: These are available through GPO Access (see “Codes”, above) only for the 104th (1995-1996) and later sessions of Congress. Click on “legislative” (left column). Once that page loads, scroll down to “Public and Private Laws”. There is a link “Helpful hints for searching Public and Private Laws” that you certainly should read. Most often it will be easiest not to search these by subject term or word, but instead to look for specific public laws (by public law number) cited in the history and amendments areas following a section of the U.S. Code.

Public laws are probably best made available online through the very useful Thomas (http://thomas.loc.gov), the web page of the U.S. Congress. On Thomas, public laws are available from the 93d Congress (1973-1974) forward, but only by public law number (the number of the Congress, followed by a dash and the sequential number of the law) without any form of subject searching.

Legislative history: You might notice that Thomas also offers a variety of sources for researching on the Web some of the legislative history surrounding the passage of legislation. Legislative history is not itself law, and so I will keep comments in this section to a minimum, but it can be a useful aid to understanding the legislation itself.

Debates that occur on the floor of either house of Congress can be found in the Congressional Record, which is available and searchable through GPO Access (see above under “Codes”). Most of the detailed work on legislation, however, occurs in the committees — Reports (which usually accompany a bill a committee wants the whole house to pass) and the transcripts of Hearings are published and can often at least be identified through Thomas (you might need to use print sources or subscription web pages to actually read the full documents, there is an online tool at http://www.gpoaccess.gov/libraries.html for finding libraries that are depositories for federal documents.) Begin with the “Bill Summary and Status” link on the top of the left column of options.

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Online sources for state statutes: In general, the statutory sources for the states mirror those for the federal government, with session laws published in serial order, as “public laws” or “public acts” and some form of subject-ordered codification.

Online sources for constitutional and statutory law in each of the 50 states are linked from this page at Cornell’s Legal Information Institute (LII): http://www.law.cornell.edu/statutes.html. The LII also has an interesting page consisting of a table linking sources of state statutes by broad topical area: http://www.law.cornell.edu/topics/state_statutes.html.

The JURIST web portal hosted at the University of Pittsburgh also has a tool for searching the statutes of the various states. Go to http://jurist.law.pitt.edu/legalresearch.htm, select the “Cases and Statutes” link, and then activate the menu in the middle of the right column to select the state that interests you.

Legislative history in the states remains difficult even with the full print and subscription resources of a law library. Web-based sources, however, are beginning to make this process easier. Indiana University Law Library has a good general pathfinder for state legislative history (http://indylaw.indiana.edu/library/State_Leghist.htm). The legal-research web-zine, LLRX.com, also has a very helpful article on state legislative history at http://www.llrx.com/columns/reference34.htm. There are also Web-based pathfinders compiled by law libraries and others that can best be located by searching Google or another search engine for “state legislative history” or for “legislative history” and the name of a particular state.

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Case law:

The decisions of courts are another source of law in American jurisdictions. The traditions and practices regarding which courts’ decisions are binding as precedent upon which other courts, and under what circumstances, are quite complicated and outside the scope of this guide. Case law both interprets and applies the constitutional and statutory law of the relevant jurisdictions and (at the state level, only) governs in the remaining “common law” areas where a superceding statute has not been passed. The decisions of trial courts are often not published at all, especially at the state level. Appellate decisions — opinions in cases on appeal — are frequently published, are more important as sources of law, and are generally easier to locate online.

Each state has a court system, and so does the federal government. For an example of how a court system is structured, the federal courts have district courts — which are the main trial courts and can hear cases that meet certain requirements to be within the federal jurisdiction. Some of these cases result in written and published opinions, which are printed in reporters called the Federal Supplement, now in its second series. There are then appellate courts, called Circuit Courts for historical reasons. The circuit courts cover the country by region with an additional “Federal Circuit” for certain special matters. These are called “intermediate courts” because they are inferior to the Supreme Court. The opinions of the intermediate federal appellate courts are very often published, in the Federal Reporter, which is now in its 3d series. The U.S. Supreme Court has a jurisdiction that is discretionary (they choose what cases to hear) and because of the small size of the court even many extremely important, law-making, cases end with the Circuit Courts. Supreme Court cases are reported in the United States reporter, and also in a couple of commercially-published unofficial reporters. Many states follow a similar, three-tiered, system – although the names of the courts may differ significantly.

While the opinions in many cases can be found on the Web, it is very difficult to search or research case law online. This is because there is no (freely available) unified, searchable, database of court opinions (with the partial exception of the new Lexis-owned LexisOne web site, at http://www.lexisone.com/caselaw/freecaselaw). The text of a known, recent, case from an upper-level state or federal court can very often be found online, in a database of that court’s opinions, but it is often impossible to discover unknown case law or research case law without the materials available in a law library. The major traditional way to locate case law on a topic (besides the high-priced commercial services Lexis and Westlaw) is with a set of print volumes called a Digest. If you are able to visit a local law library, your librarian can assist you in learning to use a Digest.

Since it is usually helpful to locate secondary sources and statutory law first, however, you may already have a sizeable list of known cases that you want to look at, drawn from annotations or notes in those other sources. There are a number of databases on the Web containing (relatively recent) cases from specific courts or jurisdictions — usually you can access a case with either its citation or its title (party names). The West-owned but free site FindLaw links to a list of these sources under the “Laws: Cases and Codes” heading (http://www.findlaw.com/).

Cornell’s Legal Information Institute has a chart of links to databases of the Supreme Court (http://supct.law.cornell.edu/supct/) other federal courts (http://www.law.cornell.edu/federal/opinions.html) and of the highest court in the New York court system (http://www.law.cornell.edu/ny/ctap/).

Emory University Law Library has a useful ‘Federal Courts Finder’ that uses a clickable map of the federal judicial circuits to link to sources of case law from various federal courts (http://www.law.emory.edu/FEDCTS/). The source used for the case-law of each of the circuits linked through this page is either a web page of the court itself or of another law school.

The JURIST web portal, hosted at the University of Pittsburgh, also includes on its legal research page a utility for searching the case law of various courts. Go to http://jurist.law.pitt.edu/legalresearch.htm and click the “Cases and Statutes” button.

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Court Information:

Federal Courts:
It might be useful to begin with the Federal Judiciary homepage, at http://www.uscourts.gov. This page includes links to the specific courts, links to the Judicial Conference (the policy making body for the judiciary), and a link to materials on the rule-making activities of the federal judiciary. The Louisiana State University libraries also host a page with links to various federal court websites, at http://www.lib.lsu.edu/gov/Judicial/.

Court Rules:
In most court systems the judiciary, acting through the Supreme Court of the jurisdiction, has a procedure for creating court rules. These are rules that govern permissible court procedure – e.g. the timing and form of filings and the requirements for presenting or objecting to evidence.

The Federal Rules of Civil Procedure are available through the Legal Information Institute at http://www.law.cornell.edu/rules/frcp/overview.htm. Many local (i.e. specific to certain individual courts) federal court rules are available through the U.S. Courts ‘Federal Rulemaking’ page, at http://www.uscourts.gov/rules/index.html.

For state court rules, try the web page of the state court system. LLRX, a web-zine for legal researchers, also has a finding tool for court rules (and docket information) at http://www.llrx.com/courtrules/.

Court Records:
Court filings or records (pleadings and briefs of parties, indictments, etc.) are generally difficult to find except for directly from the court. Sometimes, especially with very prominent cases of current-events interest, it is worth searching the Web with a search engine (try the name of the case and the name of the court or, if a federal or state agency is a party, for example the Dept. of Justice in a federal criminal prosecution, try the web site of the agency). More generally, for state courts try to search the court’s web site and see if they make filings publicly available. Federal courts have a long-term plan to make civil filings more freely available online — at present you will usually have to register for the PACER system (an acronym for Public Access to Electronic Records) first, however: http://pacer.psc.uscourts.gov/). The Judicial Conference (the policy-making body for the federal courts) has recently decided that the federal courts will not make the records and filings in criminal cases public over the Internet, however — they are still officially public records but you will need to go to the court itself.

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Administrative Law:

Administrative law is the law of regulations passed by administrative agencies. This is the law that “fleshes out” the statutory law and deals with particular issues for which Congress lacks the time or the expertise. The two major forms of administrative law are regulations (rules created by administrative agencies) and rulings (or quasi-judicial decisions) by administrative agencies or administrative-law courts (usually with some method of appeal by a law court available).

The ABA Administrative Procedure Database, hosted by Florida State University College of Law, provides many links focused on state and federal administrative law, especially on the procedural rules of various administrative hearings: http://www.law.fsu.edu/library/admin/

Federal administrative regulations are published first in the daily Federal Register, and are then codified in the Code of Federal Regulations (which is the regulatory analog to the statutory U.S. Code). The Federal Register and the Code of Federal Regulations are both available through GPO Access. Go to http://www.gpoaccess.gov/index.html and select “Regulatory”, in the left column. Although there are guides to each document, that are made available with the web versions, you may have an easier time asking a law librarian to help you with the print editions. One thing that might help is to remember that the Code of Federal Regulations is a functional cousin of the U.S. Code – it is divided into titles and ordered by subject – and the Federal Register, like session laws, is published chronologically.

Some links to federal administrative decisions are also available through GPO Access. Go to http://www.access.gpo.gov/su_docs/index.html and select “Administrative decisions” in the left column.

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This page was created by Andrew Larrick.