In legal research, secondary sources refer to legal writing that does not emanate from the courts or the legislature. Also called commentary, these sources are the work of one or more authors who describe, summarize, analyze, or comment on the law.
In common law jurisdictions, commentary is "secondary" in that these sources are not the law itself, compared to "primary" sources (case law and legislation). They can, however, can be considered persuasive by the courts, and some authors are cited regularly in jurisprudence.
The reason they are emphasized in the legal research process is for two main functions:
Both are important for efficient legal research. Primary sources—especially cases—are available in such high volume for the modern researcher that it can be very difficult to find and identify the most important cases on a legal issue. Commentary provides the most effective approach to legal research.
You can think of secondary sources in two general categories.
Traditional sources existed long before online research became our default legal research paradigm. Non-traditional source types have emerged since and, in some cases, are continuing to emerge.
| Traditional Secondary Sources | Non-Traditional Secondary Sources |
|
Textbooks Treatises Legal encyclopedias Journal articles Looseleafs |
Blogs Grey Literature Social media Law firm websites AI-generated content? |
This distinction will be important when we review the strengths and weaknesses of different formats for your research. It also affects how you will locate these resources, since many traditional source types are not easily findable via a Google search and must instead be found through specialized access points.
►See "The Availability of Information Online" in Christa Bracci & Erica Friesen, Online Legal Research (eCampus Ontario Open Library, 2024) for more information on finding traditional sources via Google.
