However, dissatisfaction with the rather stilted explanations which were produced led to a search for some more natural form of explanation, and there were several suggestions that the form of explanations could be improved by presenting them as arguments. Initially the output of rule based models of law relied on the standard how and why explanation, as pioneered in the MYCIN project. Only much later were these techniques harnessed for the prediction of case outcomes.Ģ.2.Argument for presentation and explanation This stress on generation of arguments rather than their evaluation continued in CABARET and BankXX which generated its arguments through heuristic search of a collection of argument pieces. In the third, rebuttal, stage, these challenges are met by distinguishing the counter examples, emphasising the distinction if appropriate downplaying the distinctions made in the second stage and citing additional cases to emphasise strengths and downplay weaknesses.Ī second feature of this kind of argumentation is that there was no attempt made to evaluate arguments: all the emphasis was on the generation of arguments, and the onus was on the user to decide which ones were strong and convincing. In the second stage this is challenged either by providing a counter example, at least as good as the cited case, or by distinguishing the cited case, and if possible, emphasising the distinction. Essentially in the first stage a case is cited, with the suggestion that its decision be followed in the current case. Typical of this style of analysis we see the dialogue divided into a sequence of stages (the three plies of the HYPO model), and moves to present arguments characteristic of each of these stages.ĬATO has eight argument moves. HYPO drew especially on the oral hearing stage of the US Supreme Court. Even though the model is computational (the algorithms involved in HYPO were given in Appendix A of ), the analysis relates to the informal argument tradition which attempts to provide a description of legal argumentation from consideration of examples of actual practice. In and some additional structure was provided by the identification of the argument moves that the participants use to present their arguments within these three plies.Ī key point about this approach is that there was no formal, theoretical, underpinning. This structure is a very natural way to organise legal arguments of the sort found in the high level US court decisions used by HYPO since it closely follows the structure of Oral Hearings in the US Supreme Court. In the third ply the proponent attempts to rebut the opposing arguments by distinguishing the counter examples and down playing the differences, arguing that they are not significant. ∗ By citing features in the current case but not the precedent, or in the precedent but not the current case, to distinguish the current case from the precedent. ∗ By citing the precedent with a different outcome which most closely matches the current case as a counter example. AI and Law therefore offers an excellent domain in which to explore the impact of Dung’s seminal paper by examining the differences his ideas made. įor these reasons AI and Law has always needed to concern itself with argumentation and there was a good deal of work before appeared in 1995. Open texture was introduced by Waismann in and adapted for use in law by Hart. Law, however, is not like that many concepts are vague in that a new instance may or not fall under them, and require resolution in the light of arguments as to why and why not a given instance should be considered to do so. According to Frege, logic requires that its concepts have sharp boundaries. Sometimes also, as social values change, law has to change to adapt to the new values, and cases are decided differently. Moreover, even once a decision has been made, it can be overturned on appeal, so that arguments which prevailed at one level of court may fail at a higher level. Legal rules can be overturned by finding that an exception applies, or by finding a conflicting law, or by distinguishing the case so that the rule does not apply. If acceptance is not achieved, challenges to the argument of the decision will form the basis of an appeal to a higher court. In law, the answer is not enough: the reasons for the answer must be given in order to guide future decisions, to ensure consistency of decisions, and to attempt to persuade the losing side of why they lost, perhaps leading to acceptance of the decision. The counsel for the parties to the dispute put forward arguments for their clients and the judges choose which to accept. Law (at least in US and UK) is adversarial.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |