국가계약법령의 물가변동에 따른 계약금액 조정규정에 위배되는 계약금액 고정특약의 효력에 관하여-대법원 2017. 12. 21. 선고 2012다74076 전원합의체 판결을 중심으로

In the subject case (Supreme Court en banc Decision 2012Da74076 Decided December 21, 2017), the key issue was the judicial validity of the special terms excluding the application of the provision on the adjustment of contract amount according to price fluctuation under the Act on Contracts to Which the State Is a Party (hereinafter “State Contracts Act”) based on a public contract entered between the State, etc. and the contracting counterparty. Such issue is directly connected to the legal characteristics of the foregoing provision to which the State Contracts Act does not explicitly prescribe. Hence, the Justices on the bench were divided over whether the provision on the adjustment of contract amount is a mandatory provision through different interpretations of the legal nature of public contracts and the legislative intent of the State Contracts Act (including said provision). Inasmuch as a public contract is also a type of contract under the private law, the principle of private autonomy should be respected. However, when considering the special feature of public contracts distinct from general contracts between private persons, such as its public nature and gap in the contracting party’s status, the State should act as a guardian and become more actively involved in the execution and performance of public contracts. Against such backdrop, the provision on the adjustment of contract amount under the State Contracts Act also appears to have been legislated in its current language and form, which obligates a public official to adjust the contract amount according to price fluctuation. These aspects should be sufficiently considered in determining the legal nature of the provision on the adjustment of contract amount and the validity of special terms in violation of such provision. Deeming special terms that go against the provision on the adjustment of contract amount to be valid not only contradicts with the statutory language but also results in undermining the legislative purpose of the State Contracts Act regulating public contracts, which is to ultimately realize public interest by protecting the interest of contracting counterparties and maintaining the public nature of such contracts from its conclusion to the formation and realization of its terms. Meanwhile, deeming otherwise does not necessarily lead to causing serious harm to the safety of transaction. In view of the aforementioned circumstances, it is reasonable to construe that the provision on the adjustment of contract amount according to price fluctuation under the State Contracts Act constitutes a mandatory provision and that the special terms in violation of such provision is invalid. Moreover, the judicial branch, as the last bastion of the rule of law, ought to deny the validity of a juristic act in violation of a statute, thereby securing the unity and consistency of the legal order.