A Reduction-Graph Model of Ratio Decidendi

05/2000; DOI: 10.1145/158976.158981
Source: CiteSeer

ABSTRACT This paper proposes a model of ratio decidendi as a justification structure consisting of a series of reasoning steps, some of which relate abstract predicates to other abstract predicates and some of which relate abstract predicates to specific facts. This model satisfies four adequacy criteria for ratio decidendi identified from the jurisprudential literature. In particular, the model shows how the theory under which a case is decided controls its precedential effect. By contrast, a purely casebased model of ratio fails to account for the dependency of precedential effect on the theory of decision. 1 Introduction Every computational model of legal precedent that refers to individual past cases necessarily embodies, at least implicitly, some model of ratio decidendi, the content of a precedent that is authoritative as to subsequent cases. Predicting, advocating, and justifying the binding effect of a precedent on subsequent cases all require identifying the authoritative elements of...

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