Semantic Types for Decomposing Evidence Assessment in Decisions on Veterans’ Disability Claims for PTSD

This paper presents a semantic analysis for mining arguments or reasoning from the evidence assessment portions (fact-finding portions) of adjudicatory decisions in law. Specifically, we first decompose the reasoning into primary branches, using a rule tree of the substantive issues to be decided. Within each branch, we further decompose argumentation using two main categories: reasoning that deploys special legal rules and reasoning that does not. With respect to special legal rules, we discuss legal presumption rules, sufficiency-of-evidence rules, and the benefit- of-the-doubt rule. Semantic anchors for this decomposition are provided by identifying the inferential roles of sentences – principally evidence sentences, finding-of-fact sentences, evidence-based-reasoning sentences, and legal-rule sentences. We illustrate our methodology throughout the paper, using data and examples from a data set of veterans’ disability claims in the U.S. for post traumatic stress disorder (PTSD)