Defeasible Reasoning with Legal Rules

  • Lambèr Royakkers
  • Frank Dignum
Part of the Workshops in Computing book series (WORKSHOPS COMP.)


The last few years several defeasible deontic reasoning formalisms are developed as a way to solve the problem of deontic inconsistency. However, these formalisms are unable to deal with some very common forms of deontic reasoning, since e.g. their expressiveness is restricted. In this paper we will establish a priority hierarchy of legal rules to solve the problem of deontic conflicts and we will give a mechanism to reason about nonmonotonicity of legal rules over the priority hierarchy. The theory presented here, based on default logic and a modification and extension of the argumentation framework of Prakken, properly deals with some shortcomings of other defeasible deontic reasoning approaches.


Legal Rule Deontic Logic Argumentation Framework Conditional Norm Default Logic 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© British Computer Society 1996

Authors and Affiliations

  • Lambèr Royakkers
    • 1
  • Frank Dignum
    • 2
  1. 1.Center for Law and InformatizationTilburg UniversityTilburgThe Netherlands
  2. 2.Dept. of Mathematics and Computer Science EindhovenUniverstity of TechnologyEindhovenThe Netherlands

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