Challenges in the Interdisciplinary Use of Comparative Law

Seemingly, comparative law invites quantitative analysis: there are more than 200 sovereign states, and many of them are federations, which increases the number of jurisdictions. Yet actually, proving causal claims about the effect of some institutional detail on some outcome variable of interest with the help of comparative law is fraught with challenges. Translating (legal) text into numbers is not easy in the first place. But even if this initial step has been successful, there are the usual concerns with observational data, like reverse causality, omitted variables, or measurement error. More concerning even is the fact that legal orders do not develop independently of each other. This calls the independence assumption into question, which is at the core of any statistical analysis. The paper analyzes the challenges, discusses potential solutions, and explains why the traditional attention of comparative lawyers to institutional detail is key