Secondary sources do the initial legwork of researching the law for you by citing 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, below is a brief list of the basic sources.
*Credit: Lexis Secondary Sources Toolkit
A legal dictionary contains the definitions of legal terms taken from a variety of sources. They are the first place you should look when you do not understand what a legal term means.
Two of the most commonly used legal dictionaries are:
In addition to providing a general definition of the legal term in question, legal dictionaries may also provide references to applicable primary law and other secondary sources containing more in-depth discussions of the term.
A legal encyclopedia is a comprehensive set of brief articles on legal topics. It is arranged similarly to a general encyclopedia with topical articles arranged in alphabetical order. In the final volume(s) of most legal encyclopedias is an index.
The two most popular general legal encyclopedias are:
In addition, there are numerous state legal encyclopedias.
First, the articles can be quite useful as a general introduction to an area of law that is new to you. They provide more in-depth information than a legal dictionary while being nearly as accessible and easy to use.
Second, encyclopedias are a way to find citations to cases and other useful materials on a particular issue.
Using a legal encyclopedia is straightforward: look up your topic in the index, identify the section or sections where your topic is discussed, turn to those sections, and read them. Both can be accessed online through Westlaw and Lexis.
Legal periodicals contain articles about emerging areas of law and are written by professors, practitioners, judges, and law students. Commonly used legal periodicals include law reviews, law journals, and bar journals.
Legal periodicals are often the first secondary source to cover new and emerging areas of law and to highlight developments and changes in the existing law. In addition to providing an in-depth discussion on the legal issue, a law review or journal article also will provide citations to significant, and often recent, primary and secondary sources.
A periodical index collects information about individual articles that appear in journals, newsletters, and magazines. That information is arranged alphabetically by title, author, and subject.
ALR contains annotations, which are articles written by legal experts on very narrow legal issues. These annotations are based on cases that represent emerging, unsettled, ever-changing areas of the law, and they provide an objective analysis of the current state of the law in this area. Annotations explore the law of the jurisdictions that have dealt with this issue and cite to cases on all sides of an issue.
If you find an A.L.R. covering your topic, it is a great starting point for research. In addition to providing a summary of the legal issue, the Table of Cases, Laws, and Rules gives you a snapshot of the law across jurisdictions (federal, state, and foreign). A.L.R. annotations also identify other secondary sources, such as legal encyclopedias, treatises, and periodicals.
For online access:
There is a multi-volume ALR Index that can help you find annotations by subject. There is also a one-volume Table of Laws, Rules, and Regulations that can help you find annotations that cite particular federal statutes, regulations, and court rules, as well as state statutes and constitutions.
Treatises are books that provide in-depth treatment, usually on a single subject, such as torts or constitutional law. Treatises usually provide an overview of the subject as well as analysis and commentary. They also frequently contain citations to many primary and secondary sources. Treatises range from broad, multi-volume sets to narrowly focused one-volume titles.
Practitioners rely heavily on treatises for the detailed coverage and practical tips they contain.
You can locate relevant treatises by keyword searching in the Polar Catalog.
For Online access:
See the example below from Understanding Immigration Law regarding the English language requirement.
Restatements of the Law are a series of treatises that articulate the principles or rules for a specific area of law. They are secondary sources of the law written and published by the American Law Institute (ALI) to clarify the law.
They are the most persuasive secondary source because they can become binding law if adopted by a jurisdiction. The main volumes contain statements of the common law rules, whereas the appendices contain lists by jurisdiction of cases applying the corresponding rule.
Restatements have a subject index to find specific topics and also have Appendix volumes containing summaries of cases that have cited the Restatement.
Restatements have a subject index to find specific topics and also have Appendix volumes containing summaries of cases that have cited the Restatement. See examples below.
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