Earthquakes and Tremors in Statutory Interpretation: An Empirical Study of the Dynamics of Interpretation

Abstract

Using citation data from the Supreme Court's 1984 and 1990 Terms, this study tests three models of judicial dynamics. The first model posits that the extent of an opinion's importance to the law, as measured by how frequently it is cited by courts and commentators, is determined by a host of relatively small factors. This model predicts a normal, bell-shaped curve of citation frequencies. The second model posits that judges have bounded rationality and strong attachments to existing rules, leading them to practice normal science most of the time with occasional paradigm shifts. In empirical studies by various social scientists, this kind of model has been found to produce frequency distributions that are roughly bell-shaped but have a characteristic known as leptokurtosis. The third model stems from complexity theory (also known as chaos theory or fractal geometry. This type of model predicts a power curve that is characteristic of many social and natural processes, such as earthquake severity. Because earthquakes provide such a vivid metaphor for legal change, this can be called the tectonic model of legal dynamics. As it turns out, the first model is clearly wrong, and the second model is also at odds with the data. On the other hand, the tectonic model provides a good statistical fit for the data. Thus, at least in terms of this preliminary empirical investigation, complexity theory may provide important insights into judicial dynamics.

Keywords: Supreme Court, judges, citations, complexity theory