Using the West Key Number System as a Data Collection and Coding Device for Empirical Legal Scholarship: Demonstrating the Method Via a Study of Contract Interpretation

Empirical research is an increasingly important type of legal scholarship. Such research generally requires the collection and coding of large quantities of data. These tasks pose critical challenges for legal scholars. Most crucially, they are often resource-intensive. The primary purpose of this article is to explain how researchers can use the West Key Number System to dramatically streamline the process of data collection and coding. The article accomplishes this, in part, through a demonstration by employing the Key Number System to conduct an empirical study of contract interpretation. Contract interpretation is one of the most significant areas of commercial law. And the subject has received considerable scholarly attention during the last decade. Virtually all academic work in this field is doctrinal or theoretical. But numerous contract interpretation issues cry out for empirical investigation. The secondary purpose of this article is to test one of the central claims in the judicial and academic debate over the optimal method of contract interpretation — the claim that the “contextualist” approach to interpretation results in more litigation over the meaning of contracts than does the “textualist” approach. The results of the study set forth below are inconsistent with that thesis. By thirteen of fourteen measures, there was no statistically significant difference in the amount of interpretation litigation between textualist and contextualist regimes. And for the fourteenth measure, while there was a statistically significant difference, the result was the opposite of that predicted by textualist theory: there was more litigation under textualism.