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Legal Research Strategy

Research Overview

Legal Research Strategy

Step 1: Get Started

  • READ what you’ve been given
  • ANALYZE the facts and frame your legal issues
  • ASSESS what you know and need to learn
  • NOTE the jurisdiction and any primary law you have been given
  • GENERATE potential search terms

Step 2: Consult Secondary Sources

Step 3: Find Primary Authority

  • Use secondary sources to find primary sources
  • Use code annotations, case digests & citators
  • Repeat cases and references are a GOOD THING

Step 4: Update & Analyze the Controlling Law

  • Actually have to READ the law
  • Determine which law is RELEVANT & BINDING
  • APPLY law to your facts
  • Make sure the law you found is still GOOD LAW


Starting with Secondary Sources

Legal researchers are encouraged to begin with secondary sources such as law review articles or treatises, which are likely to lead to specific primary law such as statutory references or case citations.  

Primary law citations can then lead the researcher to additional primary law, or even back to additional helpful secondary materials.

Research Strategy Flow Chart

Remember, when searching within a specific area of law, finding repeat cases and references is a good thing! Those references reinforce the importance of your citations and allow you to use digests and citators to find additional sources within the same subject.

Secondary Sources

Using Secondary Sources

Secondary sources are a great place to begin your research. Although the primary sources of law--case law, statutes, and regulations--establish the law on a given topic, it is often difficult to quickly locate answers in them. Secondary sources often explain legal principles more thoroughly than a single case or statute, so using them can help you save time. Secondary sources also help you avoid unnecessary research, since you are tapping into work that someone else has already done on an issue.

Legal texts

Secondary sources include:

  • Legal encyclopedias
  • American Law Reports (ALR)
  • Treatises
  • Law journals
  • Restatements

Secondary sources are particularly useful for:

  • Learning the basics of a particular area of law
  • Understanding key terms of art in an area
  • Identifying essential cases and statutes

Tutorial: Lexis

Tutorial: Westlaw


Legal Encyclopedias

Legal encyclopedias contain brief, broad summaries of legal topics, providing introductions to legal topics and explaining relevant terms of art. They also provide citations to relevant primary law and sometimes give citations to relevant major law review articles.  Here are the two major national encyclopedias:

If you need help using legal encyclopedias, this guide will provide you with more information, including a list of popular state-specific sources.

Tutorial: AmJur

American Law Reports

American Law Reports

American Law Reports (frequently abbreviated and referred to as ALR) contains in-depth articles on narrow topics of the law. ALR articles, called annotations, provide background, analysis, and citations to relevant cases, statutes, law review articles, and other annotations.  ALR in print is located in the Langdell Reading Room beginning at KF 132.  The ALR Index is located at KF 132.2.I53.

Visit this guide for more information about American Law Reports.

Tutorial: ALR


Finding Treatises by Subject

Treatises--books on legal topics--are a good place to begin your research or find an answer to a question, and will help you save time by providing explanation, analysis, and tips on the most relevant primary sources. Treatises range from single volume overviews to extensively detailed multi-volume sets. They may come in the form of bound books updated with pocket parts or looseleafs with easily replaced pages. Some treatises are intended for law students while others are meant for practicing lawyers. 

If you need help finding a relevant treatise, this guide will provide you with some of the most useful titles in each subject. Where available, it is noted if the treatise is available on Lexis or Westlaw. Please keep in mind that this availability may change without notice.

Tutorial: Treatises

Law Journals

Introduction to Law Journals

Law review or journal articles are another great secondary source for legal research, valuable for the depth in which they analyze and critique legal topics, as well as their extensive references to other sources, including primary sources.

Law reviews are scholarly publications, usually edited by law students in conjunction with faculty members. They contain both lengthy articles and shorter essays by professors and lawyers, as well as comments, notes, or developments in the law written by students. Law review articles often focus on new or emerging areas of law and they can offer more critical commentary than a legal encyclopedia or ALR entry.

Some law reviews are dedicated to a particular topic, such as gender and the law or environmental law, and will include in their contents the proceedings of a wide range of panels and symposia on timely legal issues.

Finding Law Journal Articles

You can search the library catalog, Hollis+, for articles and texts together in one search frame.  In the alternative, Google Scholar is a good place to start.

In addition, many of the major databases used for primary law research can also be used for secondary source research, such as HeinOnlineLexis, and Westlaw.  Be sure to change search settings in advance or filter the results after constructing your search.

If you have questions about about searching for law review articles, visit this guide for helpful database links and information about using indexes.


Introduction to Restatements

Restatements are highly regarded distillations of common law. They are prepared by the American Law Institute (ALI), a prestigious organization comprising judges, professors, and lawyers. The ALI's aim is to distill the "black letter law" from cases to indicate trends in common law, and occasionally to recommend what a rule of law should be. In essence, they restate existing common law into a series of principles or rules.

Restatements cover broad topics, such as Contracts or Property. They are organized into chapters, titles, and sections. Sections contain a concisely stated rule of law, comments to clarify the rule, hypothetical examples, explanation of purpose, as well as exceptions to the rule.

Restatements are not primary law. Due to the prestige of the ALI and its painstaking drafting process, however, they are considered persuasive authority by many courts. The most heavily cited Restatements are the Restatement of Torts and the Restatement of Contracts.

The ALI web site contains information regarding Restatement projects, ALI membership, history and institutional processes.

Finding Restatements

The Restatements are available in print and on both Lexis and Westlaw. Visit this guide for more information about finding Restatements, including a list of Restatements by topic.

Primary Sources

Primary Sources for Legal Research

Bloomberg, Lexis, and Westlaw provide access to primary legal sources (as well as secondary sources in some cases).  Primary legal sources include:

  • Case law (decisions from state and federal courts),
  • Legislation (as passed by state legislatures and the U.S. Congress), 
  • Regulations (from both state and federal agencies).
  • Constitutions (both state and federal)
  • Treaties

Browsing by topic or practice area can help you can find cases, statutes, regulations, secondary sources and the latest information from the field all in one place.  You can search for specific terms or use the filers to refine your results.

There are also many sources of free legal legal information online.  Visit this guide for helpful links and resources.

Remember, you can use Secondary Sources as a gateway to Primary Law.  Not only do secondary sources include footnotes and annotations that can lead you directly to relevant cases, legal databases include mechanisms for linking sources by topic, known as headnotes (Lexis) and key numbers (Westlaw).


Finding Cases

You can browse and search for case law in the same way you search for primary sources, by subject, with a citation, or using keywords.  Note, however that the body of case law is so large that a general search in any legal database will likely provide an overwhelming number of results and could waste a significant amount of research time.  Instead, you should use a secondary source to identify at least one relevant case, which you can build on using the "one-good-case method."

The One-Good-Case Method

Not only can one relevant case lead you to other relevant cases in footnotes or annotations, legal databases include mechanisms for linking sources by topic, known as headnotes (Lexis) and key numbers (Westlaw).


In Lexis, headnotes show the key legal points of a case. Each headnote is written by a Lexis editor, drawing directly from the language of the court. 

"More Like This Headnote" allows you to focus on the terms of art or key words in a particular headnote. This feature uses those terms and keywords to find more cases with similar headnotes or with closely matching language in the opinions. That list of cases collected by a common headnote is known as a "digest of cases."

"Retrieve All Headnotes" shows you all case headnotes written for a specific topics and relevant cases. 

Key Numbers

In Westlaw, each legal issue in a case is identified and summarized in headnote form and then assigned a topic and key number in the West Key Number System.

Clicking on a particular key number will bring you to a digest of cases in the same jurisdiction that are all connected by that common topic.  You can change the jurisdiction of the digest to find additional cases.

You can also search key numbers directly to find relevant cases by topic and then select additional filters, such as jurisdiction or date.


Each major legal database has its own citator, and it's important to be comfortable with all three: BCite (Bloomberg), Keycite (Westlaw), and Shepard's (Lexis).  

Citators serve three purposes: (1) validation, (2) updating, and (3) additional research

Tutorial: Cases


Using Statutes for Research

Statutes are laws enacted by legislatures, such as the United States Congress.  Statutes are a great place to begin research of primary legal sources.  If you are provided a statute in your research materials, you can use annotations in the legal databases to find other relevant materials, including secondary sources and cases.

Visit this guide for more information about finding and using Federal and State statutes.

Tutorial: Statutes


Administrative Law Research

Finding and understanding regulations is a difficult research undertaking. Visit these additional guides where you can find more about administrative law research.


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