A question about legal citation mapping and analysis

[David G. Post]

To all:
    There's an enormously rich mine of citation information in various
legal databases (Lexis, Westlaw), consisting of the citations from one
case to another that form the 'web' (seamless or otherwise) of legal
precedent.  Surprisingly, perhaps, there has been virtually no analytic
work on the structure of that citation data -- notwithstanding the fact
that it is, in some respects, the best picture we have of what the
"law" actually consists of.
    I'm planning a fairly substantial attack on some of the questions
about what this citation network looks like, how it changes over time,
and the like.  My question is this:  Can anyone on this list recommend
a good source of mapping/clustering tools for producing 2-dimensional
visualizations of citation data?  Assuming that I can get my hands of
the relevant primary data (the matrix of legal decisions and all of the
citations within those decisions to prior decisions), one of the things
that I would like to do is to prepare visual depictions of the cases
within various legal subdomains -- the network, say, of all cases
dealing with the First Amendment, or copyright law, or bankruptcy law ...
   I apologize if this query is too simple-minded to answer easily; I
know that there is an enormous amount of information out there on
information visualization, and I'm just hoping that some of the members
of this list might be able to point me in productive directions.  Feel
free to reply to me off-list, if you'd like.  Thanks in advance.
David Post

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David G. Post     Professor, Temple Law School
David.Post at temple.edu             202-364-5010
<<http://www.temple.edu/lawschool/dpost/writings.html>>
<<http://www.icannwatch.org>>
SSRN:  <<http://ssrn.com/author=537>>

"There are two possibilities: Either we are alone in the universe or we
are not. Both are equally terrifying."-Arthur C. Clarke
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