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A good place to start is with a secondary source such as a treatise, looseleaf, or journal article about a particular topic. These sources often lead to a case citation right on point. From there, researchers can use a citator such as Shepard's or KeyCite to discover additional cases.
If you cannot find a secondary source on point or you want to conduct a search, you must first decide if you want to use a digest or an electronic database.
Using a Digest
If you use a digest, you should brainstorm and think about relevant search terms. To help you with this, you should browse the topic outline which is included in every digest volume. Another volume to check is the Descriptive Word Index which is shelved at the end of the digests. The Descriptive Word Index will give you synonyms or other alternative search terms.
Once you find relevant terms you can go to the appropriate digest volume and look for case decisions. Remember to always check the pocket part.
Using an Electronic Database
If you prefer to conduct an electronic search, you can choose from many databases. Each database has its own unique search features but generally an advanced search option allows to set specific parameters. Some databases allow you to construct Boolean searches using and, or, not as well as other connectors.
Lawyers and law students can choose from many electronic sources of case law. Below is a sample list of sources.
Remember to always check coverage because not every source contains case law or decisions from every jurisdiction.
You can search and find case law using Google Scholar. For more options, select the advanced scholar search which will allow you to narrow down your search to a specific jurisdiction.