Is Equivalent Wages for Equivalent Work an Illusion?: Legal principles for eliminating the disparity between regular and non-regular employees (Japanese)

The central issue regarding non-regular employees is the disparity in compensation compared to regular employees. There are three policy choices to resolve this issue: (1) the basic principle of same compensation for same career, (2) the basic principle of same compensation for same work, and (3) the basic principle of prohibiting discriminatory treatment without an objective reason. Of these choices, article 8 of the Part-time Labor Act adopts (1) the basic principle of same compensation for same career, and the Democratic Party of Japan's manifesto (2009) extols the basic principle of same pay for same work (one form of (2) the basic principle of same compensation for same work). A general legal principle based on a particular form (same career or same work) is not applicable to other types of employment systems and creates the problem of not being able to address the various benefits not directly connected to career or work duties, such as commuting allowance, in-house cafeterias, and health examinations. While France and Germany have adopted (2) the general legal principle of same compensation for same work, their systems, in fact, operate in line with (3) the basic principle of prohibiting discriminatory treatment without an objective reason in order to resolve the issue. With an assumption of diverse and broad benefits for employees and diversified and multi-track human resource systems (wage systems), Japan has also adopted (3) the basic principle of prohibiting discriminatory treatment without an objective reason; responses that incorporate diversity of particular situations for determining objective reason are likely appropriate in terms of theory and practice. In this paper, I clarify in concrete terms the details and nature of this principle (in particular, guidelines for interpreting objective reason and the concrete framework for decisions) while looking at various aspects such as the debate in France and Germany and show how to respond to problems in implementing this principle (low predictability).