취업규칙 불이익변경 여부의 판단 방식과 기준 ― 법정 정년연장형 임금피크제 도입을 소재로 ―

In South Korea, the Labor Standards Act mandates that employers establish “Rules of Employment (RoE)” to define working conditions and maintain workplace order. A critical provision of this Act (Article 94) stipulates that any modification to the RoE that is “disadvantageous” to employees requires the collective consent of the majority of employee or the majority trade union. This procedural safeguard has sparked significant legal controversy regarding the “Wage Peak System,” a measure adopted by numerous companies following the 2013 statutory amendment that extended the mandatory retirement age to 60. While this system guarantees employment up to the new limit, it simultaneously imposes a reduction in wages for the extended years to alleviate the financial burden on employers. This paper provides a critical legal analysis of whether the introduction of such a Wage Peak System constitutes a “disadvantageous change” to the RoE, thereby triggering the mandatory consent requirement. The study primarily challenges the prevalent argument from employers that establishing terms for the newly extended employment period amounts to the “creation” of new rules rather than a “change” to existing ones. The author argues that once an RoE is established, any subsequent addition or modification—regardless of whether it covers a previously undefined period—must be legally categorized as a “change” and subject to strict scrutiny. Furthermore, the paper delves into the substantive assessment of “disadvantage.” Employers often contend that since the retirement extension results in a net increase in total lifetime income, the accompanying wage reduction does not constitute a disadvantage. However, this paper refutes this “total income” perspective. It posits that reducing the wage rate for the same value of labor inherently undermines the employees' vested interests and their legitimate expectation of equitable treatment. The extension of the retirement age is a statutory obligation, not a valid quid pro quo that allows employers to unilaterally lower labor standards. Consequently, the author advocates for a judicial approach grounded in the principle of “in dubio pro operario”—when the disadvantageous nature of a change is ambiguous, it should be presumed disadvantageous. This interpretation is essential to protect the employees' right to self-determination by ensuring they can exercise their right to agree or disagree through the mandatory collective consent process. The study concludes that the introduction of a Wage Peak System without valid collective consent is procedurally flawed and legally invalid, emphasizing the need to uphold the fundamental principle of the equal determination of working conditions between labor and management.