Argumentation in AI and Law: Editors' Introduction

1. Overview Argument is central to law: legal disputes arise out of a disagreement between two parties and, since the disappearance of trials by ordeal and combat, such disputes are resolved by the parties to the dispute presenting arguments for their position to an agreed arbiter, who will typically justify the choice of the arguments he accepts with an argument of his own, intended to convince superior courts and the public at large. Given the centrality of argument to law, it is unsurprising that AI systems intended to model legal reasoning have found it necessary to model argument. This volume contains a collection of papers representing some of the very latest work on argumentation in AI and Law. The papers derive from a workshop run in conjunction with the Tenth International Conference on AI and Law, held in Bologna in June 2005. The papers have since been significantly extended and revised for publication here. In this introduction we will try to provide some of the context in which this work was done. We will not pretend to give a complete survey, but rather to introduce the key concerns and issues relating to argumentation which have arisen in previous work in AI and Law. Major topics which have emerged as important in AI and Law and argumentation include: – Arguing on the basis of precedent cases – Using argumentation to resolve rule conflicts and explore defeasibility – Dialogue and dialectics – Argument Schemes – Determining whether an attack on an argument is successful We will briefly consider each of these in turn.