Changing meaning of the rule of law

Abstract Significant scholarly effort has been dedicated to defining the rule of law. The prevailing view in the literature is that the rule of law is a highly multidimensional and, as some suggest, an essentially contested concept. In this study, we employ advanced text-as-data methods, specifically diachronic word embeddings, to shed light on what the rule of law means and how its meaning has evolved over a century through parliamentary speeches in the UK and the US. We categorize the conceptualization of the rule of law into thin (procedural) and thick (substantive) definitions. Our findings indicate that procedural elements, such as rules and judiciary, maintain a strong and relatively more stable association with the rule of law. In contrast, substantive elements, which include rights and democratic principles, have become relatively less associated with the rule of law over time. Despite this decline, the rights component remains critically important to the concept, broadly equivalent in significance to procedural aspects. Because our analysis is confined to parliamentary debates from the UK and the US, the findings should be interpreted with caution when generalizing to other political contexts.