The academic paper entitled The Authority of Supreme Court Precedent: A Network Analysis can be found using the following link:

http://jhfowler.ucsd.edu/authority_of_supreme_court_precedent.pdf

This academic paper provides an in-depth explanation of how network analysis can be applied to study Supreme Court precedents. A network was constructed that consists of 30,288 majority opinions written by the U.S. Supreme Court from 1754 to 2002. The paper describes a method for creating hub and authority scores that can be used to identify the most important and most influential cases in history. The method used is a direct application of what we learned in class about hub and authority scores before Spring Break.

The following describes how hub and authority scores are used in the study:

“The authority score of a case depends on the number of times it is cited and the quality of the cases that cite it. Symmetrically, the hub score of a case depends on the number of cases it cites and the quality of the cases cited. Thus, authority scores indicate the degree to which a case is thought to be important for resolving other important issues that come before the Court, while hub scores indicate the degree to which a case is well-grounded in previous important rulings” (3). “A case that is a good hub cites many good authorities, and a case that is a good authority is cited by many good hubs” (12).

At a basic level, one could just use the number of inward citations to measure a case’s importance. This is the method of degree centrality. The problem with this method is that it does not use all the information given in the network to arrive at a conclusion because it treats all citations with the same weight. Another method is eigenvector centrality which indicates important cases using a computed vector of importance scores. However, this method biases downward the importance of recent cases and also assumes that only inward citations contain information about a case’s importance. Using hub and authority scores allows both inward and outward citations to be considered when assessing importance of cases. The study of cases using the hub and authority scores method facilitates the most accurate identification of key precedents in the network.

The above comparison relates to the idea of distinguishing between nodes in a network that have multiple reinforcing endorsements and those that simply have a high in-degree. This was touched on in Homework 4 from last week and was also mentioned in class. The method of using hub and authority scores is a much more comprehensive and accurate method than the others described.

In addition to identifying importance, authority scores are also used in the study to detect the rise and fall of precedent, to analyze changes in the issues that the Court prioritizes, and to study changes in the importance of competing legal rules within a certain area of law. The paper is able to verify its findings by successfully matching the results of important cases found using network analysis with evaluations by legal experts.