1. The lower court: (a) paid a certain amount of wages to the doctors employed by the Plaintiff based on macro evidence, and paid a certain amount of wages instead of Class A earned income tax; (b) stated the agreed amount in the account book with the intent to reduce the burden of Class A earned income tax; and (c) omitted the hospital income amount in order to secure the financial resources; (b) found that additional amount of wages other than the amount of expenditure on the account book amount reaches KRW 223,356,670 in 198, and KRW 275,806,670 in 198. However, even though the Plaintiff’s additional amount of wages paid in addition to the amount of payment on the account book should be deducted in calculating the amount of income as necessary expenses corresponding to the total amount of income in the pertinent year, the lower court rejected the Plaintiff’s assertion that the instant disposition of taxation without deducting the amount of wages on the account book violates the principle of trust and good faith by making a false entry in order to reduce the burden on Class A earned income on his own, and by collecting the difference between the Plaintiff’s and the aforementioned payment.

2. However, even if a taxpayer made an obstacle to the exercise of tax authority by falsely recording books and collecting and paying less Class A employment income tax that should be withheld at source, the tax authority has the authority to conduct a field investigation against the taxpayer, and the tax authority is in a superior position to impose various additional taxes on a bona fide taxpayer. In this case, even in this case, the tax authority has verified the omission of the above revenue through the field investigation and caused taxation. In the case of tax law, the tax authority has the characteristics that the principle of legality is more strongly required by the principle of no taxation without law. Meanwhile, in calculating the amount of income, the sum of expenses corresponding to the total amount of income in the corresponding year should be deducted as necessary expenses (Article 31 of the Income Tax Act). Thus, when the tax authority proves that the taxpayer's failure to deduct necessary expenses corresponding to the omission of the revenue, if it proves that the taxpayer has proved the omission of necessary expenses corresponding to the omission of the revenue, it cannot avoid the imposition of necessary expenses corresponding to the omission of the revenue amount due to the above legal principle or the principle of no taxation without law.

Therefore, the judgment of the court below is erroneous in the misapprehension of legal principles as to the principle of trust and good faith and the principle of notions, and there is a ground to point this out.

3. Therefore, without examining the remaining grounds of appeal, we reverse the judgment of the court below and remand the case to the court below. It is so decided as per Disposition by the assent of all participating Justices.

Justices Kim Sang-won (Presiding Justice)