[2] Whether the main text of Article 78(1) of the former Act on Acquisition of and Compensation for Land, etc. for Public Works Projects and the main text of Article 78(4) of the same Act that stipulate the duty to establish and implement relocation measures is a mandatory law (affirmative)

[3] The meaning of "basic living facilities according to the relevant regional conditions, such as roads, water supply facilities, drainage facilities, and other public facilities" under Article 78 (4) of the former Act on Acquisition of and Compensation for Land, etc. for Public Works Projects

[4] In a case where a person subject to relocation measures is required to pay the cost of basic living facilities as stipulated in Article 78(4) of the former Act on Acquisition of and Compensation for Land, etc. for Public Works Projects to the project operator, etc. by including the cost of basic living facilities in the sale price under a special supply contract for housing or housing entered into between the person subject to relocation measures and the project operator, whether the project operator shall return the amount equivalent to

1. Article 78(1) of the former Act on the Acquisition of Land, etc. for Public Works and the Compensation therefor (amended by Act No. 8665, Oct. 17, 2007; hereinafter “former Public Works Act”) provides that “A project operator shall either establish and implement relocation measures or pay resettlement funds to those who lose their base of livelihood as a result of the provision of residential buildings due to the implementation of public works (hereinafter “persons subject to relocation measures”), as prescribed by Presidential Decree.” Article 78(2) of the former Enforcement Decree of the Act on the Acquisition of Land, etc. for Public Works and the Compensation Therefor provides that a project operator shall establish and implement relocation measures or pay resettlement funds to those who lose their base of livelihood as a result of the provision of residential buildings due to the implementation of public works (hereinafter “persons subject to relocation measures”), and Article 40(2) of the former Enforcement Decree of the Housing Act provides that a project operator shall provide housing to those subject to relocation measures, such as housing supply and drainage facilities, in accordance with the Housing Site Development Promotion Act.”

In full view of the above provisions, the supply of housing sites or houses (hereinafter “special supply”) by the project implementer to the persons subject to the relocation measures under the proviso of Article 40(2) of the Enforcement Decree of the former Public Works Act, such as the Housing Site Development Promotion Act or the Housing Act, is a method of taking the relocation measures that the project implementer may choose on the basis of delegation under Article 78(1) of the former Public Works Act. Therefore, in the case of special supply, it is reasonable to deem that the person subject to the relocation measures should install the basic living facilities under Article 78(4) of the former Public Works Act at the expense of the project implementer and provide them to the persons subject to the relocation measures, as in the case of providing the relocation settlement site. It does not change on the ground that the market price of housing sites or houses

In addition, the purpose of the former Public Works Act is to promote the promotion of public welfare and the appropriate protection of property rights through the efficient implementation of public works by prescribing matters concerning compensation for losses incurred by the acquisition or use of land, etc. required for public works through consultation or expropriation. Measures for resettlement under the said Act is a system that is prepared to restore the previous living conditions to those subject to relocation measures who lose their base of livelihood by providing land, etc. necessary for the implementation of public works and ensure a living worthy of human dignity at the same time. Thus, Article 78(1) of the former Public Works Act, which provides for the duty to establish and implement relocation measures, and Article 78(4) of the same Act, which provides for the contents of the measures for resettlement, is a mandatory law that can not be excluded from the application by agreement of the parties or at

Furthermore, the purpose of Article 78(4) of the former Public Works Act is to provide the person subject to relocation measures with a basis of living. Thus, the term "basic living facilities according to the relevant regional conditions, such as roads, water supply facilities, drainage facilities, and other public facilities" under the said provision means roads, water supply and drainage facilities, electric facilities, telecommunications facilities, gas facilities, or district heating facilities, which are installed by a project operator who implements a housing construction project or a housing site development project under the relevant statutes, such as Article 23 of the Housing Act.

Therefore, if a person subject to relocation measures pays to a project operator, etc. the cost of installing basic living facilities under Article 78(4) of the former Public Works Act by including the cost of installing basic living facilities under the said provision in the sale price under a special supply contract for a housing site or housing contract entered into between a person subject to relocation measures and a project operator or a supplier under his/her arrangement, it is that the project operator bears the cost of installing basic living facilities to be borne by the project operator in accordance with the said provision. Ultimately, the project operator gains a profit equivalent to the cost of installing basic living facilities without any legal cause and has suffered a loss equivalent to the same amount. Thus, the project operator must return the amount to the person subject to relocation measures as unjust enrichment (see, e.g., Supreme Court en banc Decision 2007Da63089, 63096, Jun

2. The reasoning of the judgment of the court of first instance cited by the court below is as follows: (1) as of January 19, 2005, the defendant announced the authorization of the implementation plan for the Incheon Urban Planning Facility with respect to the business of building owners of residential buildings, including the plaintiff, who owned the housing and lost their base for living under the public works project of this case on 2005-11 of Incheon Metropolitan City, to the extension of 2,060m, width of 50m, 50m, and the project of building access roads to the Incheon Urban Planning Facility (hereinafter “instant public works”); (2) as of November 7, 2005, as of 2005, the public works of the free economic zone authority of Incheon, as of 200,000,000,000 won under the former Public Works Projects Act, and (3) as to the construction of the apartment complex to newly construct and supply the apartment complex to the plaintiff pursuant to Article 78 of the Act on Relocation Measures for Residents.

In light of the above facts in light of the legal principles as seen earlier, since the Plaintiff received the instant apartment from the Incheon Urban Development Corporation, which appears to include the cost of basic living facilities, by the Defendant’s recommendation, from the general sale price, which appears to have been included in the cost of basic living facilities, the lower court should have ordered the Plaintiff to return the amount of unjust enrichment equivalent to the amount of the Defendant’s unjust enrichment on the ground that the Defendant’s exemption from the disbursement of the amount corresponding to the cost of basic living facilities to be borne by the Defendant under the above provision without any legal ground and the Plaintiff suffered losses equivalent to

Nevertheless, the lower court did not recognize the Defendant’s establishment of the obligation to return unjust enrichment equivalent to the Defendant’s cost of installing basic living facilities on the premise that there is no room for application of Article 78(4) of the former Public Works Act in the event that the instant apartment was specially supplied as a part of the relocation measures. In so doing, the lower court erred by misapprehending the legal doctrine on the project operator’s duty to install basic living facilities in

3. Therefore, the lower judgment is reversed, and the case is remanded to the lower court for further proceedings consistent with this Opinion. It is so decided as per Disposition by the assent of all participating Justices on the bench.

Justices Lee In-bok (Presiding Justice)