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1L Legal Research Primer

What is a citator?

Citators developed as a way to check that a case was still good law.  They are useful in a variety of contexts – updating statutes, finding additional sources, etc., but they are really important in determining whether you can rely on a case. Because cases are published chronologically and geographically, they are not ever organized by subject or updated the way statutes are. Without a citator, there’s no way to tell if a case has been overturned or otherwise criticized or questioned
  • Tools for validating your case research built in to electronic databases: Shepard’s (Lexis) and Key Cite (WL)
  • They compile the prior and subsequent history of a case, including other sources that cite it.
  • Most important function is to help you determine that your research is up to date and that a case (or statute) is still good law.
  • Also an excellent tool for expanding your research

Using CItators to Update

  • History – traces this particular case as it moved through the court system.
  • Citing References – cases that have cited this case
    • Flags negative treatment -  identifies subsequent cases that have overruled, limited, or otherwise diminished a case’s precedential value.
  • Review those cases carefully to assess their effect on your case.
  • Citators are very cautions. Negative treatment does not necessarily mean that a case is invalid.

Using Citators to Expand your Research

  • Citing references tabs compile documents that cite your case favorably, including cases, statutes, secondary sources, regulations, and court documents.
  • Table of Authorities tab creates a list of documents cited in your case.
  • Both tools are efficient ways to locate additional sources.

Shepard's v. Keycite

  • Shepard’s is the original citator system, developed by Lexis.
  • KeyCite is a functionally equivalent system, developed by Westlaw.
  • Both are used to determine whether cases and statutes (but especially cases) are good law. Both can also be used to expand your research by identifying additional sources.
  • Both have options to narrow results by jurisdiction, headnote, depth of treatment, date, etc.
  • Lexis and Westlaw use different, proprietary, headnote systems, and Shepard’s and KeyCite are keyed to those systems.

What do citator symbols mean?

Citators use colored flags and other symbols to quickly indicate the status of your case (or statute). In general:

Green/Blue

Positive Treatment

Yellow

Caution. 
Possible negative treatment - the authority may distinguish or criticize an aspect of yourcase.

Red

Case is no longer good law on at least one legal point 
Designed to grab your attention and flag any possible negative treatment of a case.
 
Remember that negative treatment does not mean that a case is invalid.