Why did medieval universities usually not teach local customary law?

In medieval European universities, local and customary legal systems were generally excluded from the curriculum because they were viewed as parochial and, therefore, unworthy of academic study.1

Instead, medieval universities focused on "learned law," which consisted of Roman law and canon law. Scholars at institutions like the University of Bologna sought to derive universal legal principles from these texts, which were considered more suitable for the scholarly, systematic approach of the time. In contrast, local customary laws were uncodified, varied significantly by region or demographic group, and were often administered in local manorial or feudal courts rather than through the academic legal science developed in universities.21

It was not until the 18th century that the study of national or local laws began to be integrated into university programs in most European countries.1