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Case Law Research: Updating Case Law

This guide provides information on Case Law Research, and identifies pertinent print and online resources available through the NYU Law Library

Updating Cases

The law is constantly evolving.  It is important to always check to make sure the case you have found is still good law, and to be aware of what other courts held on the relevant points of law.  This has often been referred to as "Shepardizing" a case.  There are two main case law citators to verify the status of your case - on LexisNexis, it is Shepards and on Westlaw it is Keycite.  Keyciting and Shepardizing are also a method for finding other cases and secondary sources relevant to your topic.

KeyCite: KeyCite will let you see the history of the case you are checking - earlier rulings in the same litigation, as well as subsequent history in the case - rulings after the opinion you are interested in; KeyCite will also provide a link to "Citing References" to view a list of cases, administrative materials, secondary sources, briefs, and other court documents that cite your case.

Shepards:also provides both prior and subsequent history of the case, as well as tabs for "Citing Decisions" for other cases which cite to your case, and "Citing Law Reviews, Treatises, . . . and other Secondary Sources" including court documents.

Both citators use signal indicators to let you know what type of subsequent history or treatment the case has received.  Red flags (Westlaw) or red stop signs (LexisNexis) will let you know that there has been negative treatment of your case - that part of the case was overruled or reversed.

Sources for Updating Cases