Legal information is constantly being updated. When you are researching a piece of law, like a case, you will need to keep up to date with what is going on with that particular piece of legal information. For this, you can use a legal citator, either in print or online.
Citators are valuable to help you determine whether a case is still "good law," or overruled by another decision, or whether a statute has been found unconstitutional. Citators achieve this by listing all citing references to the case or statute that you are researching. In other words, it lists all pieces of law (cases, statutes, etc) that have discussed, mentioned or impacted your case, either positively or negatively, since that ruling.
To check for citing references in print, you will use Shepard's Texas Citations series. To use the print citator, you will need the case citation for the case that you are researching.
For full instructions for Shepardizing in Print, see the Guide available from Lexis: How to Shepardize: Your Guide to Legal Research Using Shepard's Citations in Print
Important: be sure to check all available supplements to find all of the citing references your case! To make sure that you check everything, look for the paperback supplement with the most recent date and look at the list of books on the cover under "What Your Library Should Contain." This will list each of the volumes and supplements that you need to be sure to check.
The online citator subscribed to by LSC-North Harris Library is KeyCite. Like the print citators, KeyCite tracks the citing cases (cases that cite the case that you are researching). Since online content is updated daily, there are no supplements to check to make sure that you are getting the latest information.
Treatment = indicates how that case affected your case (the case that you are researching). Westlaw will list all negative treatment first, and then all other treatment in date order.
Depth = how much that case talks about your case. The more the green bar is filled in, the more your case was discussed.
Headnote(s) = which points of law were discussed in regards to your case
For further details in using Westlaw's KeyCite, see the Westlaw Guide: Checking Citations in KeyCite.