Reasoning with portions of precedents
L. Karl Branting · 1991
This paper argues that the task of matching in case-based reasoning can often be improved by comparing new cases to portions of precedents. An example is presented that illustrates how combining portions of multiple precedents can permit new cases to be resolved that would be indeterminate if new cases could only be compared to entire precedents. A system that uses of portions of precedents for legal analysis in the domain of Texas worker's compensation law, GREBE, is described, and examples of GREBE's analysis that combine reasoning steps from multiple precedents are presented. 1 Introduction A central problem in automated legal reasoning is that many legal predicates lack definitions that provide necessary and sufficient conditions for their satisfaction (McCarty, 1990; Gardner, 1984). Such legal predicates are said to be "opentextured. " Open texture in legal predicates is an instance of the broader phenomenon of category polymorphy (Rosch and Mervis, 1975), the absence of precise...