[Plaintiff, Appellee] Plaintiff's litigation representative Attorney Lee Seok-tae and 2 others
[Defendant, Appellant] Daewoo Electronics Co., Ltd., litigation representative Attorney Lim Dong-jin and 1 other
[Lower Court Judgment] Seoul Civil District Court, Judgment rendered January 9, 1991, Case No. 90Na5671
[Order]
The appeal is dismissed.
The costs of the appeal shall be borne by the Defendant.
[Reasoning]
(1) As to the first ground of appeal.
According to the reasoning of the lower court judgment, the lower court, based on the evidence presented, found the following facts: that the Plaintiff joined non-party Daehan Electric Wire Co., Ltd. (대한전선주식회사) on March 17, 1969, and worked there as a technical employee, and around June 1976 was reassigned to a Grade 5 administrative position, and was promoted to a Grade 4 administrative position on June 6, 1978; that on February 5, 1983, non-party Daehan Electric Wire transferred its electronics and electrical business division and its industrial equipment business division to the Defendant, and, in connection with this transfer of business, it was agreed that the Defendant would take over all employees of non-party Daehan Electric Wire as of March 1, 1983, but that, with respect to retirement allowances, each individual employee would be permitted to freely decide whether (i) not to receive a retirement allowance at the time of the business transfer, but instead to receive, upon later retiring from the Defendant company, a retirement allowance calculated by aggregating the years of service from the date of joining non-party Daehan Electric Wire to the date of retirement from the Defendant company, or (ii) to receive a retirement allowance calculated for the period from the date of joining non-party Daehan Electric Wire to February 28 of that year (the date of the business transfer), and thereafter be treated as newly joining the Defendant company as of March 1 of that year, with a new period of service to be calculated from that date until retirement, for purposes of a new retirement allowance; that, accordingly, on February 28 of that year, the Plaintiff selected the option of, upon retirement from the Defendant company, receiving a retirement allowance calculated by aggregating the years of service from the time of joining non-party Daehan Electric Wire; and that the Plaintiff, even after the above transfer of business, continued to work in the same position and perform the same duties as before, until retiring on December 31, 1988; and, upon finding these facts, the lower court held that the period of service forming the basis for calculating the Plaintiff's retirement allowance is the period from the time the Plaintiff joined non-party Daehan Electric Wire to the time the Plaintiff retired from the Defendant company.
As to the Defendant's argument that the Plaintiff, having initially stated an intention to receive a retirement allowance calculated by aggregating service from the time of joining non-party Daehan Electric Wire, subsequently withdrew that intention of his own accord, received a retirement allowance for the period from the date of joining to February 28, 1983, and then went through the procedure of newly joining the Defendant company on March 1 of that year, such that the prior employment relationship was severed, the lower court rejected this argument on the ground that there was no evidence sufficient to establish that the Plaintiff had voluntarily withdrawn the expressed intention regarding payment of the retirement allowance, received the retirement allowance up to the time of the business transfer, and then newly joined the Defendant company, whereas it was established that the Plaintiff continued to work in the same position even after February 28 of that year as before, and that the Plaintiff had been paid annual leave allowances and long-service allowances calculated by aggregating years of service from the time of joining non-party Daehan Electric Wire until retirement from the Defendant company. Upon examination of the record, the above fact-finding and determination by the lower court are acceptable, and it cannot be said that there is any error in violation of the rules of evidence or any illegality due to failure to exhaust deliberation, as argued in the grounds of appeal. This ground of appeal is without merit.
(2) As to the second ground of appeal.
According to the reasoning of the lower court judgment, the lower court, with respect to the Defendant's argument that, if the Defendant's treatment of the Plaintiff as having undergone an interim retirement is invalid, then the Plaintiff received the interim retirement allowance without any cause, and therefore the amount equivalent to statutory interest on that money should be deducted, as unjust enrichment, from the retirement allowance that the Defendant is obligated to pay the Plaintiff, rejected this argument on the ground that the interim retirement allowance was paid by the Defendant on its own initiative, against the Plaintiff's wishes, as an advance payment of part of the retirement allowance, and moreover that there was no assertion or proof that the Defendant had demanded the return of the interim retirement allowance so as to place the Plaintiff in default of the obligation to return unjust enrichment.
However, Article 743 of the Civil Act (민법) provides that where an obligor, by mistake, performs an obligation that is not yet due, the obligee must return the benefit thereby obtained; therefore, it was erroneous for the lower court, while recognizing that the Defendant's payment of the interim retirement allowance to the Plaintiff constituted performance before the due date, to base its rejection of the claim for return of unjust enrichment arising therefrom not on whether the Defendant, as the party performing the obligation, acted by mistake, but on whether the Plaintiff, as the recipient, acted voluntarily; and it was also erroneous for the lower court, in response to the Defendant's claim for return of unjust enrichment in the amount equivalent to the statutory interest gained by the Plaintiff as a result of performance before the due date, to determine the matter by reference to whether there was an obligation to pay delay damages arising from delay in returning the interim retirement allowance.
However, the phrase "by mistake" under Article 743 of the Civil Act means that the party did not know that the obligation was not yet due, and thus applies only where the party performed the obligation under the mistaken belief that the due date had arrived; a person who performs an obligation while knowing that it is not yet due is to be regarded as having waived the benefit of the time limit. Therefore, since, as found by the lower court, it cannot be established that the Plaintiff, having selected the option of receiving, upon retirement from the Defendant company, a retirement allowance calculated by aggregating years of service from the time of joining non-party Daehan Electric Wire, subsequently reversed that intention of his own accord to adopt the interim retirement method and received the interim retirement allowance (rather, according to the testimony of the witness, a non-party, which the lower court did not reject, and the overall purport of the pleadings, it appears that the Defendant paid the interim retirement allowance to the Plaintiff against the Plaintiff's wishes, in order to reduce the burden of retirement allowances for administrative staff), even if the Defendant paid the interim retirement allowance to the Plaintiff and the Plaintiff received it, it is difficult to regard this as the Defendant having, by mistake, performed an obligation before its due date.
This is because it is difficult to believe that a large enterprise such as the Defendant was unaware that such treatment as an interim retirement had no effect as a retirement; and even if the Defendant had been unaware of this, such lack of awareness would only be attributable to gross negligence; moreover, if the Defendant, knowing that the interim retirement treatment was invalid, nevertheless carried it out forcibly out of the company's own necessity, this should be regarded merely as having the same result as paying the retirement allowance before its due date while waiving the benefit of the time limit.
This being so, in this case, where there is no other circumstance shown that would establish that the Defendant's payment of the interim retirement allowance was made by mistake, the Defendant's argument that the unjust enrichment in the amount equivalent to statutory interest arising from performance before the due date should be deducted from the retirement allowance that the Defendant is obligated to pay to the Plaintiff must be rejected; therefore, although there is some error in the reasoning set forth by the lower court, there is no error in its conclusion rejecting this argument, and this had no effect on the outcome of the judgment. This ground of appeal is also without merit.
(3) Therefore, the appeal is dismissed, and the costs of the appeal are to be borne by the losing party; this judgment is rendered as stated in the Order, by the unanimous opinion of the participating Justices.
Justice Lee Jae-seong (Presiding Justice), Lee Hoi-chang, Bae Man-woon, Kim Seok-su