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Legal Practice Handout: Secondary Sources

Introduction

Secondary sources are a great starting point for your research, especially when you’re researching an unfamiliar area. They can help you identify or refine your legal questions, determine the relevant jurisdiction, and learn the right terminology. You can also cite to them as persuasive authority or use them to gather citations to primary authority.

Some types of secondary sources:

  • Encyclopedias provide an overview of all major legal topics and are usually arranged alphabetically.
  • Treatises are print or online books that explain and analyze a legal topic such as torts or contracts. They’re usually more detailed than encyclopedias and are written for a broad audience including scholars, students, and attorneys.
  • Practice guides are like treatises but are written specifically for attorneys and often feature forms, checklists, and practice tips.
  • Law review articles can offer a narrower focus and more detail than other secondary sources, but they’re not always suitable for practical legal questions.
  • American Law Reports (ALR) is a series of detailed articles on narrowly defined legal questions, prepared by editors at West. Each article provides an overview of the law nationwide.
  • Restatements of Law offer blackletter rules of law based on analysis of state case law nationwide, with case annotations.

Start with Encyclopedias, Treatises, or Practice Guides

Encyclopedias, treatises, or practice guides can be either state-specific, federal, or national. National sources cover state law on a nationwide basis and usually offer more detail than their state-specific counterparts.

You can discover relevant encyclopedias, treatises, or practice guides through:

For some topics, certain treatises stand out as leading authorities, like Wright & Miller’s Federal Practice and Procedure or Nimmer on Copyright. To identify leading treatises, consult research guides or ask a librarian or senior attorney for a recommendation.

Still not sure where to begin? American Jurisprudence 2d (AmJur) is a national legal encyclopedia that can help you get started. Access AmJur on Westlaw or AmJur on Lexis.

Once you get to a relevant secondary source, don’t forget the table of contents—it’s often the best way of internally navigating your source. Sometimes an index will also be available.

Using Law Review Articles or ALR

After reviewing encyclopedias, treatises, or practice guides, you might consult law review articles or American Law Reports (ALR) for more detail.

To run a full-text search for law review articles, options include:

To browse law review articles by topic, visit our Law Journal Indexes page. Browsing by topic is a good choice when you’re having trouble formulating a full-text search.

ALR on Lexis features full-text searching. ALR on Westlaw offers full-text searching, plus browsing by topic and an index. Cross-references in ALR articles can point you to additional resources on your topic.

Using the Restatements

The Restatements are useful for supplementing state case law research. There are separate Restatements for different topics, including Torts, Contracts, and Agency. The Restatements aren’t state-specific, but you can use their case annotations to see if your state is following a Restatement rule. Access the Restatements on:

Updating Secondary Sources

For most secondary sources, the updating is already done for you, usually on an annual basis. For online versions, the updates will be integrated into the text, while for print versions you might find an update in a separate supplement.

To confirm updates in online versions, look for a date at the top or bottom or the screen. You may need to click on a source information link, which will often appear as an “i” symbol. For print versions, check the publication date in the main volume and the dates of any supplements.

Law review articles are not updated. If you’re using a secondary source that hasn’t been recently updated, it’s especially important to consult current primary sources as well.

Citing Secondary Sources

It’s often appropriate to cite secondary sources as persuasive authority in your memos and briefs. Generally, you should cite secondary sources as a supplement to primary authorities, but for informal memos or when handling novel legal questions, you might cite only secondary sources.

Different types of secondary sources carry different weight, and some aren’t appropriate for citation at all.

A four-column table with header cells in the first row. This table organizes secondary sources by authority level.
Most Authoritative Authoritative Less Authoritative Don't Cite

Leading treatises
Law review articles
Restatements

Other treatises
Practice guides

Encyclopedias
Law review student notes

 ALR

Next Steps

Secondary sources alone might be enough to answer simple questions, but you should usually consult primary sources as well to confirm the information you’ve found. This is especially important if your secondary source is not specific to your jurisdiction or hasn’t been recently updated. Look at any relevant statutory law next.