Published on January 24, 2022 by Ed Craig, Reference Librarian  
Secondary sources are those legal materials which provide commentary, explanation and analysis of primary law (court and agency decisions, statutes, and regulations) in various formats and levels of authoritativeness. Librarians and legal research instructors alike recommend using secondary sources to begin research of a legal problem to gain the necessary background information to effectively understand a topic’s primary law and the issues surrounding it. In other words, why not use a legal commentator’s concise research on your topic, rather than reinvent the wheel?
In deciding what secondary sources to use, there are some general rules to consider. If your issue is jurisdiction specific, you may want to determine whether there is a treatise or law journal article that covers your topic from the perspective of that jurisdiction. As an example, while the first treatise that comes to mind on the law of torts may be THE LAW OF TORTS, by William L. Prosser and W. Page Keeton, KF/1250/.P7/1984b (2nd Floor), a tort question within the Alabama jurisdiction may be more easily answered by ALABAMA TORT LAW, 6TH ED., by Michael L Roberts and Gregory Cusimano, KFA/195/.R65/2015 (Reference).[1]  An article or book that discusses the state of the law in the form of a general, national overview may be less informative with respect to your specific jurisdiction’s law.[2] 
Another consideration in choosing secondary sources is how specific the work is to your topic. A subject specific treatise (particularly a multi-volume set) or article will more likely cover the intricate details of issues surrounding your topic, as well as provide citations to the primary law that affects your subject matter. 
Another issue which you may want to consider in choosing a secondary source is its authoritativeness; while this may be a lesser consideration in beginning the research process, it may be a prime factor later when looking for secondary sources to cite as persuasive authority in court briefs. Charles R. Calleros, in LEGAL METHOD AND WRITING, 4TH ED. (KF/250/.C34/2002), gives a good general rule in using secondary sources before the court. He states that unless a court has expressly adopted the point of view of a secondary source, such as a rule enunciated in a restatement, or “[H]as already incorporated the content of a secondary authority into its primary authority, you should use secondary authority only as a starting point in your analysis.” [3] He goes on to say that secondary authority can “[H]elp develop an argument not fully addressed or supported by primary authority.”[4]

Finding Secondary Sources--Getting Started

How do you proceed to find appropriate secondary sources? It really depends upon what information you already have. If you have a code provision, it is quite common for that code’s editors to cite to secondary sources in the code section’s annotations.  The “style of the case” (case name) in an appellate court decision can be used as a keyword phrase in periodical indices (see discussion below of Legaltrac and Index to Legal Periodicals) to find articles on point. If it is a famous case, you might try searching the library’s online catalog with that keyword phrase to find a treatise about the case.  
If you have no primary law, a law review or journal article is a good place to start. If a recent, on-point article can be found, you may already have the means of understanding the basic concepts of the topic. Within a relatively short essay, a law review article can discuss the important case law, statutes, and side issues involving a topic. It will also likely provide footnotes listing other important secondary sources central to the topic. Just as important, the reader will typically find concept terminology unique to that legal topic which can be used later to refine your research queries in CALR databases (such as Lexis and Westlaw) for more secondary sources or primary law.

Good Online Options for Finding Law Review Articles On Point

A good place to begin to find a law review article on point is the LegalTrac database, available on the Law Library website by clicking on “Online Library” at the homepage and then selecting “LegalTrac” from the databases list (unless you are using the public catalog terminals in the Law Library, you will also need to enter your Samford ID and password before entering any of the library’s subscribed databases). LegalTrac indexes most law reviews and journals for the United States and many journals from British Commonwealth nations dating back to 1980. This database provides a direct link within its own content to some of the legal profession’s prominent serial publications; more often, there will be a link within an article’s listing that will take you directly to the digital image of the print version of the article within HeinOnline (see below). Are the number of results for your search query too voluminous to handle? You can further limit those results by clicking on the most pertinent LegalTrac subject headings for your query which are found on the left side of your results page.
If your research involves issues prior to 1980, a field or advanced search of the Law Journal Library of HeinOnline (also to be found by clicking on the “Online Library” at the Law Library homepage) is a good option. While this database service has devoted most of its energies to adding older volumes of law periodicals to its online collection, there are many instances where it holds the most current issue of a publication. HeinOnline’s main purpose is to provide a full-text service that displays a digital image of the printed pages of articles and documents within the database–it is not, per se, an index. However, it does provide raw full-text searching of its content without the benefit of the extensive indexing to be found in LegalTrac and Index to Legal Periodicals. 
Legal Source (previously Index to Legal Periodicals & Books)
Legal Source is another indexing service providing coverage of law periodicals within the United States and British Commonwealth nations. The coverage this service provides depends upon the particular publication indexed; for some prominent titles, the indexing coverage commences as early as the 19th century. Also, this service includes full-text of some of the later periodical issues, sometimes in digital format, other times not. In any event, as with LegalTrac, you are given the option from the article citation to “check for full text” by clicking directly to the digitized print text found in HeinOnline, if it is available there. 
Westlaw and Lexis
The two best known legal database services, Lexis and Westlaw, have large law periodical databases with powerful search capabilities, though there are substantial gaps in coverage, particularly with respect to pre-1990 issues. As a result, if you are examining an issue with a significant chronological history which needs to be researched, Lexis and Westlaw may be less effective than a database such as HeinOnline.
If you have any questions about secondary legal source research, please contact a reference librarian. 
[1]Also, researchers should remember that there are many jurisdiction-specific treatises on Lexis or Westlaw, if the work is not available in the law library.  (West or Thomson Reuters legal publications will usually be on Westlaw and Lexis Publishing or Matthew Bender Publications will be on Lexis.)
[2]At the same time, a general overview found in a legal encyclopedia such as American Jurisprudence, 2nd or Corpus Juris Secundum may be a good preliminary step to determine the issues involved with the topic and the keyword terms which relate to it.
[4]Id. at 80.