West American Digest System

The West American Digest System is a system of identifying points of law from reported cases and organizing them by topic and key number. The system was developed by West Publishing to organize the entire body of American law. This extensive taxonomy makes the process of doing case law legal research less time consuming as it directs the researcher to cases that are similar to the legal issue under consideration.

The problem of finding cases on a particular topic was a large problem for the rapidly growing American legal system of the 19th century. John B. West, the founder of West Publishing, described this problem in his article A multiplicity of reports. To solve the problem, he developed a system with two major parts. First, his company published cases in many American jurisdictions in bound volumes called reporters (the West National Reporter System now covers all state and federal courts). Second, he put together a classification system in which he divided the law into major categories which he called topics (such as "Contracts"). He then created hundreds of subcategories. To save space in printing, these were given a number called a key number. He then applied this "topic and key number" system to the cases he published. The key number is identified in the books with a key number and a key symbol graphic.

Each case published in a West reporter is evaluated by an editor who identifies the points of law cited or explained in the case. The editor places the summaries of the points of law covered in the case at the beginning of the case. These summaries are usually a paragraph long, and are called headnotes. Each headnote is then assigned a topic and key number. The headnotes are arranged according to their topic and key number in multi-volume sets of books called Digests. A digest serves as a subject index to the case law published in West reporters. Headnotes are merely editorial guides to the points of law discussed or used in the cases, and the headnotes themselves are not legal authority.

West publishes West's Analysis of American Law, which is a complete guide to the topic and key number system, and it is revised periodically.

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