1. Most authoritative statement of rule(s) from high court.
2. Most recent reaffirmation of rule(s) from the binding lower courts.
3. Which case most approximates your case facts? Do any highly analogous cases exist in other jurisdictions (especially if their overall legal principles are similar)? Typically, real world assignments do not precisely match precedents. The best lawyers are those who see connections between cases with superficial dissimilarities. 
4. Which cases state the principles in the most advantageous way? In which cases does the position you represent win (e.g., the defendant, the movant, etc.)? 
5. What trouble lurks in the cases that your opponent will exploit in attacking your arguments? 
6. What trends can be identified in the cases (e.g., “no court has ever . . .”)? 
7. What overarching principles can you synthesize into a framework to demonstrate to a court, even if the framework is not specifically articulated by courts? Are there related principles that may help support arguments you want to make? 

This guide discusses researching case law using Lexis, Westlaw and Bloomberg Law, the commercial databases most frequently used in law firms.  However, there are many free options for conducting case law research online. 

See the Library of Congress's Guide for more information:

This research guide was last revised and updated on 8/22/2019.