Court judgments contain valuable information on how statutory laws and past court precedents are interpreted and how the interdependence structure among them evolves in the courtroom. Data-mining the evolving structure of such customs and norms that reflect myriad social values from a large-scale court judgment corpus is an essential task from both the academic and industrial perspectives. In this paper, using data from approximately 110,000 court judgments from Japan spanning the period 1998–2018 from the district to the supreme court level, (...) we propose two tasks that grasp such a structure from court judgments and highlight the strengths and weaknesses of major machine learning models. One is a prediction task based on masked language modeling that connects textual information to legal codes and past court precedents. Another is a dynamic link prediction task where we predict the hidden interdependence structure in the law. We make quantitative and qualitative comparisons among major machine learning models to obtain insights for future developments. (shrink)

Einstein’s razor, a corollary of Ockham’s razor, is often paraphrased as follows: make everything as simple as possible, but not simpler. This rule of thumb describes the challenge that designers of a legal system face—to craft simple laws that produce desired ends, but not to pursue simplicity so far as to undermine those ends. Complexity, simplicity’s inverse, taxes cognition and increases the likelihood of suboptimal decisions. In addition, unnecessary legal complexity can drive a misallocation of human capital toward comprehending and (...) complying with legal rules and away from other productive ends. While many scholars have offered descriptive accounts or theoretical models of legal complexity, most empirical research to date has been limited to simple measures of size, such as the number of pages in a bill. No extant research rigorously applies a meaningful model to real data. As a consequence, we have no reliable means to determine whether a new bill, regulation, order, or precedent substantially effects legal complexity. In this paper, we begin to address this need by developing a proposed empirical framework for measuring relative legal complexity. This framework is based on “knowledge acquisition”, an approach at the intersection of psychology and computer science, which can take into account the structure, language, and interdependence of law. We then demonstrate the descriptive value of this framework by applying it to the U.S. Code’s Titles, scoring and ranking them by their relative complexity. We measure various features of a title including its structural size, the net flow of its intra-title citations and its linguistic entropy. Our framework is flexible, intuitive, and transparent, and we offer this approach as a first step in developing a practical methodology for assessing legal complexity. (shrink)

With the ratification of Multilateral Environmental Agreements the countries of the international community or of intentional communities—be they political, economic, financial, securitarian or strategic—endow these instruments of international cooperation with significant autonomy. From the 3550 dates of ratification of these MEAs recorded from 1979 to mid-September 2014, we produce a graph whose vertices are the 48 MEAs and whose links are induced by the succession of ratifications in time. On this basis we propose a diagnosis on the international acceptance of (...) this type of legal instruments and their vulnerability in a global context that builds on the change in the balance of powers as a result of globalization, the break of the bipolar and then unipolar system, and the rise of new powers. Thus, it appears that a global environmental order has been promoted and implemented with some success in the 90s mainly by liberal Western countries who were then able to lead other countries less likely to bind to the fulfillment of environmental obligations. However, the expansion of this global environmental order now seems frozen, due to the current crisis of multilateralism. The rise of many countries, particularly in the South, whose environmental, political and economic weight grew, confronted with the “stable community” formed in the past 35 years suggests that there is a real power shift in the international arena and consequently, multilateralism needs to reflect this new reality. In other terms, the global environmental order is being slowly reformed. As a consequence, the treaties formed clusters in the past but they did not follow the same pattern since the twenty-first century began. (shrink)