Of the part against the plaintiff in the judgment below, the part of corporate tax for each business year of 2006 and 2007 shall be reversed, and this part of the case shall be reversed.

The grounds of appeal are examined.

1. Article 81-4(1) of the former Framework Act on National Taxes (amended by Act No. 11604, Jan. 1, 2013; hereinafter the same) provides that “tax officials shall conduct a tax investigation to the minimum extent necessary to realize proper and fair taxation, and shall not abuse their right of investigation for any other purpose, etc.” (Article 81-4(2) provides that “tax officials shall not conduct re-investigation into the same tax item and the same taxable period unless they fall under any of the following subparagraphs,” and subparagraph 3 of Article 81-4(1) provides that “in cases where re-investigation is exceptionally permitted, one of the cases where there is error in relation to

Article 81-4 (1) of the former Framework Act on National Taxes provides that a tax investigation shall be conducted within the minimum scope necessary for appropriate and fair taxation. Paragraph (2) of the same Article provides that a repeated tax investigation for the same item and taxable period may seriously infringe not only the taxpayer's freedom of business or legal stability, but also lead to abuse of the right to conduct a tax investigation. In principle, a re-investigation shall be prohibited, while a tax investigation may be conducted in exceptional cases where it is clearly contrary to the principle of fair taxation.

In light of the purport of Article 81-4 of the former Framework Act on National Taxes to prohibit illegal tax investigations and prevent abuse of tax investigation authority, exceptional grounds for re-audit should be met at the time of commencement of re-audit. Thus, only when the tax authority initiates re-audit based on specific data to support that there is any error or omission in calculating the tax base and amount of taxes through two or more business years due to one cause, it shall be legitimate re-audit under Article 81-4(2)3 of the former Framework Act on National Taxes.