Arguing with Dimensions in Legal Cases

In this short paper we introduce some novel arguments based on legal cases represented as sets of dimensions. Although there has been much work on arguments based on factors, there has been relatively little recent work which has exploited dimensional representations. The arguments that we consider have a flavour quite distinct from those generated from cases represented as factors, which lack notions of more and less favourable, and the original argumentation with dimensions from HYPO and CABARET, which always has the complete set of active dimensions in view. We would argue that the arguments produced have a good intuitive appeal and correspond to some kinds of argument commonly found when reasoning with legal cases. We consider in this paper arguments based on one and two dimensions, leaving additional dimensions largely for future work. Illustrations are provided using a set of cases well known and frequently represented in AI and Law. Although admittedly preliminary, we believe that arguing with dimensions in this way may enable a useful addition to the repertoire of legal arguments based on cases which can be used in AI and Law.