Although this is not my forte nor am I in the legal field, I did find this definition.  Bob, you most probably know this definition and I am not sure if this will assist you in any way, but I thought I would post it anyway.  In my experience, most legal case files are kept in "case files" and filed somewhat similar to "project files".  The entire case would have the same file series number(s).

A landmark decision is the outcome of a legal case (often thus referred to as a landmark case) that establishes a precedent that either substantially changes the interpretation of the law or that simply establishes new case law on a particular issue. Certain cases within this category are widely know in legal studies and may be reviewed by law students even if they have been overturned by later decisions.
http://en.wikipedia.org/wiki/Landmark_case

John

John A. Gervais
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