The most widely used classification system for American law.
West attorney-editors index cases under more than 400 topics and 100,000 points of law, allowing you to quickly find other cases that address your exact point of law in any jurisdiction.
This arrangement of breaking a court opinion into its distinct points of law and then classifying each point with a number has worked so well that the West Key Number System has become the de facto classification system for all American law.
Key numbers let you search for legal concepts, not just words.
Much legal research is a hunt for principles or concepts not easily retrieved with word searches.
West topic and key numbers enable you to find cases stating or applying a legal concept, even if those terms aren't in the opinion. And by adding Key Numbers to your word searches, you can narrow your search results and still get the cases you want.
Only the West Key Number System can show you cases with concepts not stated in the opinion. And it's easy to find the right key number for your issue by navigating the outline on Westlaw.
Key numbers lead you to relevant cases in other jurisdictions.
With key numbers, finding one case on point leads you directly to others – in your jurisdiction or any other – so you don't miss important law.
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View a demo »In an age of databases and word searches, do we still need indexing systems to find relevant cases? Watch this two-minute video to find out.
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This quick reference shows how to search using topic and key numbers, and it lists West digest topics and their numerical designations alphabetically and by topic specialty.