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Secondary Sources Research Guide

This guide explains various types of secondary sources, including legal encyclopedias and American Law Reports, and how to use them.


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Introduction: Getting Started on the Right Foot!

Which sounds like an easier way to start your research project: researching the law by locating every relevant case, statute, and regulation on your own, or using a source that already references primary sources of law on your topic? 

Secondary sources do the initial legwork for you by citing to primary and secondary authorities related to an area of law, and they often explain that area of law more thoroughly than would a single case or statute. There are several types of secondary sources, but let's start with the basics.

Types of Secondary Sources

Legal Dictionaries contain definitions of legal terms.
Legal Encyclopedias contain an alphabetical summary of major legal topics.
Legal Periodicals contain articles written on various legal topics.
American Law Reports annotations include a summary of a narrow legal topic along with a multijurisdictional table of laws.
Legal Treatises provide in-depth commentary on a specific legal topic.
Restatements of the Law codify common law and can become binding if adopted.

Secondary Sources (Online)

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Update History

Updated 06/2015 (MK)
Updated 08/20 (CMC)
Links 07/2023 (VL)