When Precedents Clash

Abstract

Consistency of case bases is a way to avoid the problem of retrieving conflicting constraining precedents for new cases to be decided. However, in legal practice the consistency requirements for cases bases may not be satisfied. As pointedout in [6], a model of precedential constraint should take into account the hierarchical structure of the specific legal system under consideration and the temporaldimension of cases. This article continues the research initiated in [18,9], whichestablished a connection between Boolean classifiers and legal case-based reasoning. On this basis, we enrich the classifier models with an organisational structurethat takes into account both the hierarchy of courts and which courts issue decisions that are binding/constraining on subsequent cases. We focus on common lawsystems. We also introduce a temporal relation between cases. Within this enrichedframework, we can formalise the notions of overruled cases and cases decided perincuriam: such cases are not to be considered binding on later cases. Finally, weshow under which condition principles based on the hierarchical structure and onthe temporal dimension can provide an unambiguous decision-making process fornew cases in the presence of conflicting binding precedents.