Treatment of Legal Sentences Including Itemized and Referential Expressions - Towards Translation into Logical Forms

This paper proposes a framework for analyzing legal sentences including itemized or referential expressions. Thus far, we have developed a system for translating legal documents into logical formulae. Although our system basically converts words and phrases in a target sentence into predicates in a logical formula, it generates some useless predicates for itemized and referential expressions. We propose a front end system which substitutes corresponding referent phrases for these expressions. Thus, the proposed system generates a meaningful text with high readability, which can be input into our translation system. We examine our system with actual data of legal documents. As a result, the system was 73.1% accurate in terms of removing itemized expressions in a closed test, and 51.4% accurate in an open test.