42 Pages Posted: 7 Dec 2006

Abstract

Although citation to precedent in judicial opinions is a critical component of the network of rules that comprise "the law" in any area, there have been surprisingly few systematic attempts to use the abundant data available on citation patterns to uncover general principles that might illuminate the nature and structure of the legal system. In this paper, we use data from the New York Court of Appeals and the Seventh Circuit regarding the number of times judicial opinions cite to, and are subsequently cited as, precedent to test the hypothesis that legal arguments and legal doctrine have a kind of "fractal" structure. Our model provides a reasonable fit to the citation data that we examined, although there appear to be significant sources of variability in these data that are not explained by our simple predictive framework, and it is clearly far too early to draw any robust conclusions about the hypothesis other than that additional work along these lines appears to be warranted.