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Case Law Research

How to do effective case law research using online & print resources.

Key Numbers & the Digest System

How do I search for cases on a certain topic using print resources?

Case law digests are a very powerful tool for conducting efficient case law research using print resources.

West, the chief publisher of the reporter system, developed a system for classifying the content of legal opinions called the key number system. The key number system created 414 broad legal topics into which all legal matter can be sorted. The broad topics are then divided into more specific subtopics and key numbers, which allow researchers to zero in on very specific legal subject matter.

Key numbers from West's Texas Digest

Example of subtopics and key numbers within the digest topic "Automobiles" from West's Texas Digest — © 2013 West Publishing Company. Click to enlarge.

West editors review cases to identify the important points decided in the opinion and assign them a key number based on the specific legal subject matter addressed. The headnote section of the cases contains relevant key numbers and a brief summary of the legal aspect of the case that relates to each key number. You'll see these headnotes in the database versions of these cases, too.

Headnotes assigned to a case in the South Western ReporterHeadnotes assigned to a case in the South Western Reporter

Example of headnotes and key numbers assigned to a case in the South Western Reporter — © 1980 West Publishing Company. Click to enlarge.

Lexis Advance's system of Legal Topics functions in much the same way by classifying points of law according to their list of pre-determined Legal Topics.

The digest system is a way of finding cases based on subject matter. Digests are arranged by topic and key number. The section for each key number lists the cases that have had that key number assigned to them by West editors as illustrated above. Knowing the key number for the point of law that you're interested in will allow you to locate similar cases by looking up that key number in the digest.

West's Texas DigestWest's Texas Digest

Example of West's Texas Digest entry for Automobiles, key number 20 — © 2013 West Publishing Company. Click to enlarge.

Using Footnotes & Annotations

What are annotations?

Another method for finding cases in print is to look at annotations and footnotes in other resources.

Annotations are references to other legal documents or library materials. These are materials the editors of the publication recommend for further research.

The start of every section in a West publication contains a set of annotations labeled Library References or Research References. Those include helpful places to turn for more information, including relevant key numbers. In the example from Vernon's Texas Statutes and Codes Annotated below, you see a section of the Texas Penal Code and its annotations. The Library References section contains a key number (highlighted in yellow and labeled with a "1" below) that West editors thought was relevant to this statute. Use that key number in the digests or Westlaw to find cases.

Most importantly, annotated statutes provide a list of Notes of Decisions (highlighted in blue and labeled with a "2" below). This is a list of notable court cases involving that statute. The Notes of Decisions is an excellent place to find cases related to a statute.

Annotated Texas statutesAnnotated Texas statutes

Vernon's Texas Statutes and Codes Annotated — © 2011 Thomson Reuters​. Click to enlarge.

See another example below taken from a legal encyclopedia called Texas Jurisprudence. Texas Jurisprudence explains and summarizes the law into very brief entries, making it a great resource for those beginning their research. The section shown is about the duty of care of parking facilities and garages. If you had a case regarding negligence by a parking facility, this might be a good place to start.

In this example, see the Research References section. The sections highlighted in yellow and labeled with a "1" below are an example of key numbers that the editors felt would be relevant to the topic discussed in this section.

Footnotes in Texas JurisprudenceFootnotes in Texas Jurisprudence

Texas Jurisprudence 3d — © 2015 Thomson Reuters. Click to enlarge.

What are footnotes?

If there are specific cases that are important to the topic, they may be listed in the footnotes. Editors cite the cases and statutes that form the basis of their summary in footnotes. Use these citations to find the cases in print reporters or legal databases.

See the section highlighted in pink and labeled with a "2" above as an example. It lists cases that were instrumental in establishing or refining the rules of law described in the encyclopedia entry.

Databases like Westlaw and Lexis Advance also provide annotated documents. Fastcase documents will have limited annotations that usually only include case law references.

Books

Available when you visit the library in person.

The library also has volumes from the National Reporter System. This consists of the Federal Reporter and Federal Supplement as well as state reporters divided by region:

  • Atlantic,
  • North Eastern,
  • North Western,
  • Pacific,
  • South Eastern,
  • South Western, and
  • Southern.

As of 2011, the library no longer updates these reporters. However, we continue to update the set of Southwestern Reporter: Texas Cases.

Note The library cannot tell you what the law means for your situation.

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