Your firm is likely to have one of the major online services, such as Congressional Universe or Washington Alert , for electronic access to indexes and full text documents. Court decisions interpret statutes or make reasoned judgments in the absence of statute. Make sure you find mandatory authority for your jurisdiction. Headnotes list major issues in case. Don't quote from them.
Digests are the indexes to court cases.
Use Table of Case Names for citation when you know the parties' names. Start in Descriptive Word Index, looking up your issue. References are to Topics and Key Numbers. Find the digest volume with your topic, and turn to the key number. Scan the digest entries for relevant cases.