(1) A tax official shall conduct a tax investigation (including investigation of tax offenses under the Procedure for the Punishment of Tax Offenses Act; hereafter in this Article the same shall apply) to the minimum extent necessary to ensure appropriate and fair taxation, and shall not abuse his or her authority to investigate tax-related matters for other purposes, etc. <Amended on Dec. 31, 2018>
(2) No tax officials shall re-investigate the same item of taxes and for the same taxable period, except in any of the following cases: <Amended on Jan. 1, 2013; Dec. 23, 2014; Dec. 15, 2015; Dec. 20, 2016; Dec. 19, 2017; Dec. 31, 2018; Dec. 31, 2022>
1. Where obvious evidence exists to admit a suspicion of tax evasion;
2. Where it is necessary to investigate a party to a transaction;
3. Where faults are found in connection with at least two taxable periods;
4. Where an investigation is conducted in accordance with a decision to conduct a re-investigation under the proviso of Article 65 (1) 3 (including cases applicable mutatis mutandis in Articles 66 (6) and 80-2) or under the proviso of Article 81-15 (5) 2 (limited to investigations within the scope as stated in the text of a decision);
5. Where a taxpayer provides a tax official with money and other valuables or helps a person provide a tax official with money and other valuables in relation to the duties of the tax official.
6. Where an investigation is conducted into a part not included in the relevant investigation, after a partial investigation provided for in Article 81-11 (3) is conducted;
7. Other cases prescribed by Presidential Decree, which are similar to subparagraphs 1 through 6.
(3) A tax official shall request the submission of account books, etc. within the minimum scope necessary for tax investigation; and shall not request the submission of account books, etc. irrelevant to the tax items subject to investigation and to the calculation of tax bases and tax amounts of taxable periods. <Newly Inserted on Dec. 19, 2017>
(4) No person shall engage in a conduct that impedes a fair tax investigation, including making a tax official violate any Act or subordinate statutes or abuse his or her power. <Newly Inserted on Jan. 1, 2014; Dec. 19, 2017>[This Article Wholly Amended on Jan. 1, 2010]