If you are researching a legal topic or issue, it is sometimes difficult to know where to begin your research. To a large extent, much depends on what you are researching and what information you have been given. For example, if you already have a citation to a primary law source (e.g., a case, statute, or regulation), you may want to begin with that source and see where it leads you. (For help in interpreting your citation, consult the USC Law Library's Guide to Legal Abbreviations and Citations. As a general rule however, it is best to begin your research with a secondary source. Secondary sources are texts that provide background information, terms of art, explanations of the law, and citations to relevant primary authorities.
There are a variety of types of secondary sources, and the best source to start with will often depend on how much knowledge you have about the law in general as well as the area of law you are researching. This guide describes five different types of secondary sources. They are listed by level of complexity, starting with the more basic sources that do not require any pre-existing knowledge about the law and ending with some of the more in-depth and analytical sources.
In this guide, you will learn how to find different types of secondary sources along with descriptions of them. One major tool for finding secondary sources is the library catalog. While this guide discusses how to effectively use the USC Law Library's catalog, ADVOCAT, to locate secondary sources, you may also find it helpful to consult the library's guide Finding Library Materials through Online Catalogs for more general guidance on how to use ADVOCAT.
When you use secondary sources, check to see if they have pocket parts (i.e., paperback pamphlets placed in the back pocket of each volume) or separate paperback supplements to keep the sets up-to-date. After reading information in a bound volume, it is always a good idea to check the pocket part or supplement for your volume to make sure you have the most current information related to your topic.
Finally, while secondary sources are very useful tools, particularly at the beginning of the research process, it is important to consider the following: