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Secondary Sources Research Guide

This guide explains various types of secondary sources and how to use them.


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What is a Legal Encyclopedia?

A legal encyclopedia is a comprehensive set of brief articles on legal topics. It is arranged similarly to a general encyclopedia, such as Encyclopaedia Britannica, with topical articles arranged in alphabetical order and an index in the final volume(s). The two most popular general legal encyclopedias are American Jurisprudence, 2d (Am. Jur.) and Corpus Juris Secundum (C.J.S.). In addition, there are numerous state legal encyclopedias, as well as encyclopedias with a more narrow focus, such as American Jurisprudence Trials.

Why Use a Legal Encyclopedia?

Encyclopedia articles can be a good starting place if you are researching an unfamiliar area of law. They provide more in-depth information than a legal dictionary, while being nearly as accessible and easy to use. Encyclopedias also include citations to cases and other useful materials on a particular issue. Legal encyclopedias, however, are not intended to be used as authoritative sources on the law in any area, and thus are never cited in briefs, memoranda, or scholarly papers.

Using Encyclopedias

Using a legal encyclopedia is straightforward: look up your topic in the index volumes at the end of the set, identify the section or sections where your topic is discussed, turn to the volume containing those sections, and read them. At the beginning of each major topic, you will find one broad and one detailed outline of what is covered in the article, both of which can help you place your specific topic in context. You'll also find a scope note that delineates the coverage of the article and explains where related issues are discussed. This is worth reading to be sure your issue is not covered elsewhere. Following these preliminary materials, you'll find the text of the article, which is updated with the pocket parts found in each volume. In addition to these standard features, each encyclopedia has its own unique features.

Am. Jur. is selective, in contrast to C.J.S.'s comprehensiveness. This means that Am. Jur. Provides citations only to the cases the editors consider the best or most important. This results in shorter footnotes, adding to the readability of Am. Jur.'s articles. In addition, this set of encyclopedias is more likely to cover important federal statutory material. Am. Jur. is also available on Westlaw and Lexis.

C.J.S. articles tend to be more comprehensive than Am. Jur. articles. C.J.S. provides citations to published cases and the U.S.C.A., as well as any appropriate West digest topics and key numbers for your subject; therefore, C.J.S. is helpful when using West digests. C.J.S. is available only on Westlaw

Encyclopedias Tutorial

Running time: 3:16 minutes

Created/updated: May 2019
Last reviewed: May 2019

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