We outline a formal theory of argumentation-theoretic reasoning which uniies and generalises many existing approaches to default reasoning, and which promises to be useful for practical reasoning in general and legal reasoning in particular. We discuss an extension of the argumentation theory to the problem of reconciling connicting arguments .

This paper argues for a proper position for legal logic in between a general theory of legal reasoning and a general theory of valid reasoning. In discussion with McCarty it argues that legal logic should not be seen as a general theory of legal reasoning, but rather as a theory of what counts as valid reasoning in the legal field. In discussion with earlier work by Verheij and the author himse...

An examination of Dutch research on legal case solving revealed that few law students get systematic instruction or testing in the technique of legal problem solving. The research being conducted at the Department of Computer Science and Law at the University of Amsterdam focuses on identifying the different functions in legal reasoning tasks in order to develop computational models which reali...

Dworkin 1977, 1985) offer insights valuable to AI, their jurisprudential analyses often raise more questions than they answer and their insights, couched in philosophical discourse, are difficult to harness computationally. Much of the knowledge used in legal reasoning is published, codified, and highly indexed. The legal system maintains extremely detailed records of its cases and commentary o...

We can observe and measure how legal decision makers use formal legal authorities, but there is no way to empirically test the determinative capacity of legal doctrine itself. Yet discussions of empirical studies of judicial behavior sometimes conflate judges’ attention to legal rules with legal rules determining outcomes. Doctrinal determinacy is not the same thing as legal predictability. The...

This tutorial presents the principles of the OASIS LegalRuleML applied to the legal domain and discuss why, how, and when LegalRuleML is wellsuited for modelling norms. To provide a framework of reference, we present a comprehensive list of requirements for devising rule interchange languages that capture the peculiarities of legal rule modelling in support of legal reasoning. The tutorial comp...

ion, however, is not enough. No matter how abstractly a rule is stated, standard logic requires the rule to state sufficient conditions for its conclusion. If intuitive terms are used at the most abstract level of description, then the logical structure of these conditions is in general much too complex to be quickly grasped and applied. Of course, any complex set of conditions can be represent...