This paper is an introduction to a virtual special issue of AI and Law exploring the legacy of the influential HYPO system of Rissland and Ashley. The papers included are: Arguments and cases: An inevitable intertwining, BankXX: Supporting legal arguments through heuristic retrieval, Modelling reasoning with precedents in a formal dialogue Game, A note on dimensions and factors, An empirical investigation of reasoning with legal cases through theory construction and application, Automatically classifying case texts and predicting outcomes, A factor-based definition (...) of precedential constraint and An improved factor based approach to precedential constraint. After describing HYPO, in this introduction to the special issue I look at various aspects of its influence on AI and Law: the developments led by Rissland at Amherst; the developments led by Ashley in Pittsburgh; the expression of these ideas in terms of rule based systems, and their subsequent formalisation; value based theories, which were inspired by a critique of HYPO; and contemporary approaches which revive the idea of dimensions. (shrink)

This paper discusses some engineering considerations that should be taken into account when building a knowledge based system, and recommends isomorphism, the well defined correspondence of the knowledge base to the source texts, as a basic principle of system construction in the legal domain. Isomorphism, as it has been used in the field of legal knowledge based systems, is characterised and the benefits which stem from its use are described. Some objections to and limitations of the approach are discussed. The (...) paper concludes with a case study giving a detailed example of the use of the isomorphic approach in a particular application. (shrink)

Modelling reasoning with legal cases has been a central concern of AI and Law since the 1980s. The approach which represents cases as factors and dimensions has been a central part of that work. In this paper I consider how several varieties of the approach can be applied to the interesting case of Popov v Hayashi. After briefly reviewing some of the key landmarks of the approach, the case is represented in terms of factors and dimensions, and further explored using (...) theory construction and argumentation schemes approaches. (shrink)

In this paper we describe a method for the specification of computationalmodels of argument using dialogue games. The method, which consists ofsupplying a set of semantic definitions for the performatives making upthe game, together with a state transition diagram, is described in full.Its use is illustrated by some examples of varying complexity, includingtwo complete specifications of particular dialogue games, Mackenzie's DC,and the authors' own TDG. The latter is also illustrated by a fully workedexample illustrating all the features of the game.

During human-human interaction, emotion plays a vital role in structuring dialogue. Emotional content drives features such as topic shift, lexicalisation change and timing; it affects the delicate balance between goals related to the task at hand and those of social interaction; and it represents one type of feedback on the effect that utterances are having. These various facets are so central to most real-world interaction, that it is reasonable to suppose that emotion should also play an important role in human-computer (...) interaction. To that end, techniques for detecting, modelling, and responding appropriately to emotion are explored, and an architecture for bringing these techniques together into a coherent system is presented. (shrink)

In this introduction I give an overview of Carole Hafner’s work and discuss the papers in this volume. The final section offers some more personal reminiscences of Carole and her contribution to the AI and Law community, from myself and other colleagues.

Biologically motivated computing seeks to transfer ideas from the biosciences to computer science. In seeking to make transfers it is helpful to be able to appreciate the metaphors which people use. This is because metaphors provide the context through which analogies and similes are made and by which many scientific models are constructed. As such, it is important for any rapidly evolving domain of knowledge to have developments accounted for in these terms. This paper seeks to provide one overview of (...) the process of modelling and shows how it can be used to account for a variety of biologically motivated computational models. Certain key ideas are identified in the subsequent analysis of biological sources, notably, systemic metaphors. Three important aspects of biological thinking are then considered in the light of computer science applications: biological organization, the cell, and models of evolution. The analysis throughout the paper is descriptive rather than formalized so that a large variety of potential applications may be considered. (shrink)

In this paper I recapitulate the ideas of Berman and Hafner (1993) regarding the role of teleology in legal argument. I show how these ideas can be used to address some issues arising from more recent work on legal argument, and how this relates to ideas associated with the New Rhetoric of Perelman. I illustrate the points with a discussion of the classic problem of which vehicles should be allowed in parks.