Legal Research Strategy

This guide will walk a beginning researcher though the legal research process step-by-step. These materials are created with the 1L Legal Research & Writing course in mind. However, these resources will also assist upper-level students engaged in any legal research project.

Legal research must be comprehensive and precise.  One contrary source that you miss may invalidate other sources you plan to rely on.  Sticking to a strategy will save you time, ensure completeness, and improve your work product. 

Follow These Steps

Running Time: 3 minutes, 13 seconds.

Make sure that you don't miss any steps by using our:

If you get stuck at any time during the process, check this out:

A legal question often originates as a problem or story about a series of events. In law school, these stories are called fact patterns. In practice, facts may arise from a manager or an interview with a potential client. Start by doing the following:

• Read anything you have been given
• Analyze the facts and frame the 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

Legal rules will vary depending on where geographically your legal question will be answered. You must determine the jurisdiction in which your claim will be heard. These resources can help you learn more about jurisdiction and how it is determined:

This map indicates which states are in each federal appellate circuit:

Once you have begun your research, you will need to keep track of your work. Logging your research will help you to avoid missing sources and explain your research strategy. You will likely be asked to explain your research process when in practice. Researchers can keep paper logs, folders on Westlaw or Lexis, or online citation management platforms.

Many researchers create their own tracking charts.  Be sure to include:

• Search Date
• Topics/Keywords/Search Strategy
• Citation to Relevant Source Found
• Save Locations
• Follow Up Needed

Consider using the following research log as a starting place: 

Westlaw and Lexis offer options to create folders, then save and organize your materials there.

For long term projects, platforms such as Zotero, EndNote, Mendeley, or Refworks might be useful. These are good tools to keep your research well organized. Note, however, that none of these platforms substitute for doing your own proper Bluebook citations. Learn more about citation management software on our other research guides:

There are three different types of sources: Primary, Secondary, and Tertiary.  When doing legal research you will be using mostly primary and secondary sources.  We will explore these different types of sources in the sections below.

Secondary sources often explain legal principles more thoroughly than a single case or statute. Starting with them can help you save time.

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

Consider the following when deciding which type of secondary source is right for you:

• Scope/Breadth
• Depth of Treatment
• Currentness/Reliability

For a deep dive into secondary sources visit:

Legal Dictionaries

Legal dictionaries are similar to other dictionaries that you have likely used before.

Legal Encyclopedias

Legal encyclopedias contain brief, broad summaries of legal topics, providing introductions and explaining terms of art. They also provide citations to primary law and relevant major law review articles.  

Here are the two major national encyclopedias:

Treatises are books on legal topics.  These books are a good place to begin your research.  They provide explanation, analysis, and citations to the most relevant primary sources. Treatises range from single subject overviews to deep treatments of broad subject areas.

It is important to check the date when the treatise was published. Many are either not updated, or are updated through the release of newer editions.

To find a relevant treatise explore:

American Law Reports (ALR) contains in-depth articles on narrow topics of the law. ALR articles, are often called annotations. They provide background, analysis, and citations to relevant cases, statutes, articles, and other annotations. ALR annotations are invaluable tools to quickly find primary law on narrow legal questions.

This resource is available in both Westlaw and Lexis:

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. They also contain comments, notes, or developments in the law written by law students. Articles often focus on new or emerging areas of law and may offer critical commentary. Some law reviews are dedicated to a particular topic while others are general. Occasionally, law reviews will include issues devoted to proceedings of panels and symposia.

To find law review articles visit:

Restatements are highly regarded distillations of common law, prepared by the American Law Institute (ALI). ALI is a prestigious organization comprised of judges, professors, and lawyers. They distill the "black letter law" from cases to indicate trends in common law. Resulting in a “restatement” of existing common law into a series of principles or rules. Occasionally, they make recommendations on what a rule of law should be.

Restatements are not primary law. However, they are considered persuasive authority by many courts.

Restatements are organized into chapters, titles, and sections.  Sections contain the following:

• a concisely stated rule of law,
• comments to clarify the rule,
• hypothetical examples,
• explanation of purpose, and
• exceptions to the rule  

To access restatements visit:

Primary authority is "authority that issues directly from a law-making body."  Authority, Black's Law Dictionary (11th ed. 2019).   Sources of primary authority include:

• Constitutions
• Statutes 
• Regulations
• Case Law

Access to primary legal sources is available through:

Statutes (also called legislation) are "laws enacted by legislative bodies", such as Congress and state legislatures. Statute, Black's Law Dictionary (11th ed. 2019).

We typically start primary law research here. If there is a controlling statute, cases you look for later will interpret that law. There are two types of statutes, annotated and unannotated.

Annotated codes are a great place to start your research. They combine statutory language with citations to cases, regulations, secondary sources, and other relevant statutes. This can quickly connect you to the most relevant cases related to a particular law. Unannotated Codes provide only the text of the statute without editorial additions. Unannotated codes, however, are more often considered official and used for citation purposes.

For a deep dive on federal and state statutes, visit:

Want to learn more about the history or legislative intent of a law?  Learn how to get started here:

Regulations are rules made by executive departments and agencies. Not every legal question will require you to search regulations. However, many areas of law are affected by regulations. So make sure not to skip this step if they are relevant to your question.

To learn more about working with regulations, visit:

In many areas, finding relevant caselaw will comprise a significant part of your research. This Is particularly true in legal areas that rely heavily on common law principles.

Running Time: 3 minutes, 10 seconds.

Up to  86% of federal case opinions are unpublished. You must determine whether your jurisdiction will consider these unpublished cases as persuasive authority. The Federal Rules of Appellate Procedure have an overarching rule, Rule 32.1  Each circuit also has local rules regarding citations to unpublished opinions. You must understand both the Federal Rule and the rule in your jurisdiction.

One Good Case Method

After following the steps above, you will have identified some relevant cases on your topic. You can use good cases you find to locate other cases addressing the same topic. These other cases often apply similar rules to a range of diverse fact patterns.

• in Lexis click "More Like This Headnote"
• in Westlaw click "Cases that Cite This Headnote"

to focus on the terms of art or key words in a particular headnote. You can use this feature to find more cases with similar language and concepts.  ​

A citator is "a catalogued list of cases, statutes, and other legal sources showing the subsequent history and current precedential value of those sources.  Citators allow researchers to verify the authority of a precedent and to find additional sources relating to a given subject." Citator, Black's Law Dictionary (11th ed. 2019).

Each major legal database has its own citator.  The two most popular are Keycite on Westlaw and Shepard's on Lexis.

This video answers common questions about citators:

For step-by-step instructions on how to use Keycite and Shepard's see the following:

Citators serve three purposes: (1) case validation, (2) better understanding, and (3) additional research.

Is my case or statute good law?

Look for:

• Parallel citations
• Prior and subsequent history
• Negative treatment suggesting you should no longer cite to holding.

Has the law in this area changed?

Look for:

• Later cases on the same point of law
• Positive treatment, explaining or expanding the law.
• Negative Treatment, narrowing or distinguishing the law.

Who is citing and writing about my case or statute?

Look for:

• Secondary sources that discuss your case or statute.
• Cases in other jurisdictions that discuss your case or statute.

For more guidance on when to stop your research see:

Automated services can check your work and ensure that you are not missing important resources. You can learn more about several automated brief check services.  However, these services are not a replacement for conducting your own diligent research.

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