One of the most important aspects of legal research is the ability to validate any case or statute that the researcher is going to rely upon. In a law library, Shepard's is the best known validation system. (Lexis uses the online version of Shepard's.) For Westlaw, the validation system is called KeyCite. It will be helpful to think of KeyCite as West's version of Shepard's.

There are several ways to access KeyCite, but you will most likely use one of the following:

1. Using Key Cite with Search Results
2. Key Cite Shortcut

1. Using KeyCite with Search Results
   After conducting a search and locating results (a list of cases), Westlaw allows you to KeyCite any of the results of that search. In fact, Westlaw will alert you if there are any negative "treatments" of those cases. (A treatment is the way another case has viewed that case. It can be positive or negative, or even neutral.)
   
   Let's say you have conducted a search and are now looking at one of the resulting cases. If there is a problem with the validity of that case, Westlaw will provide a treatment flag (Yellow or Red) on the top left corner of the page:
   
   
   A yellow flag means another case has commented on your case in a negative fashion, but does not invalidate your case.
   
   
   A red flag, however, means that your case is no longer valid and should therefore probably not be cited. (Although there is a chance that only part of your case was invalidated, most attorneys will not cite a case if any part is invalidated.)
   
   In any case, just click on the flag and you will be taken to the KeyCite page. KeyCite will provide a list of cases that have cited (or mentioned) the case being validated. In fact, Westlaw will collect those cases by type. Cases that have cited your case in a positive manner, negative manner, or just cited it without positive or negative treatment will be collected in their own groups.
   
   Typically, you only use KeyCite once you determine that the case is going to be used. However, if you see a result (case) that has a red flag associated with it, that tells you not to bother with it.
   
   
2. Key Cite Shortcut
   After clicking on one of the Tabs at the top of the page (such as Paralegal or Westlaw), you will see the Shortcuts on the left column. One of these Shortcuts is "KeyCite this citation" which looks like this:
   
   
   
   If you already have a citation, simply type it into the text box and click on Go.
   
   Westlaw will also provide indicators to alert you to a potential problem with a negative citation. KeyCite uses yellow and red flags for cases that view your case negatively:
   
   
   
   As mentioned above, a yellow flag means another case has commented on your case in a negative fashion, but does not invalidate your case. A red flag means that your case is no longer valid and should therefore probably not be cited.