The Basics of Secondary Sources – What, Why, How

February 1, 2017


Although they cannot be directly relied upon as legal authority, secondary sources remain some of the most important authorities to employ in legal arguments.

As most attorneys learned in their first year of law school, secondary sources are authorities that explain different points of law, but do not themselves carry the weight of establishing the law.  These sources come in a variety of forms, each with its own unique purposes and uses.

Considering the raw magnitude of the resources encompassed by the term, it may be helpful to first define “secondary sources.”

What are secondary sources?

Broadly speaking, if authorities like statutes and case law that establish the law are primary sources, everything else that discusses and analyzes primary sources are more than likely secondary sources.

Given the breadth of the definition, it is unsurprising that secondary sources can be as varied in nature and purpose as the different methods of evaluating statutes and case law.  For example, many secondary sources come in the form of authoritative topical treatises, some such authorities compile case law or statutes from across many jurisdictions, still others come in the form of live or pre-recorded seminars.  And that’s just scratching the surface of the total body of available secondary legal sources.

Why are they important?

If secondary sources don’t actually establish the law, why even bother with them?

There are a number of reasons why secondary sources are so essential to the practice of law. One of the chief reasons being that  secondary sources may reflect the prevailing view on how courts interpret primary sources.  Some secondary sources are so authoritative that courts themselves rely on them in their rulings.

Restatements of the Law are a prime example of such an authority.  Many courts are perfectly comfortable citing to a particular section of a Restatement to explain a particular legal issue.  Similarly, Jury Instructions are widely relied upon by state and federal courts across the country as a highly authoritative reference when submitting instructions to the jury.

Many secondary sources have value beyond being citable in a legal argument.  Specifically, many titles offer valuable insight into recent court decisions or new statutes.  Some may analyze new legal authorities to break down their meaning in more digestible terms, while others may consider the potential implications of a new ruling or law.  Still more secondary sources may examine topical legal trends or the current state of a particular area of law, based on recent court decisions or updates to statutes.

In short, because secondary sources reflect how the law is viewed, they are truly essential to a more comprehensive understanding of the law.

How can they benefit your practice?

Given the significance that secondary sources have to understanding the law, you may not need much convincing that they can enhance your legal practice; you may, however, be less clear on how specifically they can be used to this end.

For starters, as mentioned above, using secondary sources in your research process typically results in a more complete understanding of the legal topic at hand.  Being able to know not only what the law says, but also what others are saying about the law can add a distinctly reliable flavor to your legal argument.

Using secondary sources in your research process can also save you a lot of time and energy.  In particular, using secondary sources to quickly get brought up to speed in a legal area that is largely unfamiliar to you may save you the headache of reading through a slew of primary authorities indiscriminately.

Indeed, many secondary sources can even point you in the direction of the most relevant cases and statutes to review and rely upon for the legal issue being researched.  Many even neatly distill points of law from referenced primary authorities for easy consumption, making building an understanding of a previously unfamiliar area of law relatively quick and painless.

The benefits don’t end there; as diverse and expansive as are secondary sources, so, too, are the many manners in which they can bring value to your law practice.  They should always be a central ingredient of any research process to ensure that the resulting product is of the highest quality.

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