Automatic Consolidation of Japanese Statutes Based on Formalization of Amendment Sentences

摘要

To realize computer-supported works in the areas of legislation and the practical use of laws, a statute database is indispensable so that users can easily retrieve desired versions of desired statutes. However, almost all former versions of statutes need to be restored since they cannot be easily obtained or digitalized. This task can be achieved by repeatedly consolidating amendment statutes with each version of the statute from the first one. In this paper, for Japanese statutes, we show that amendment clauses, which are parts of amendment sentences, can be formalized in terms of sixteen regular expressions. We also propose an automatic consolidation system for Japanese statutes based on the formalization and experts' knowledge about consolidation. System evaluation is shown through a consolidation experiment.