There must first be a grant of letter of authority before an officer can conduct an examination or issue an assessment.

Taxpayer was issued an assessment by the Bureau of Internal Revenue, which was elevated to the CTA by the taxpayer. Upon the cross examination of the revenue officer by the taxpayer’s counsel, the examiner admitted that there was no letter of authority (LOA) issued by the BIR for the examination of the taxpayer that gave rise to the issuance of the assessment. Thus, the taxpayer raised in its memorandum that the assessment should be declared void considering that there was no LOA issued. The Court agreed with the taxpayer. Section 13 of the National Internal Revenue Code of 1997 requires the issuance of LOA. Thus, the assessment in the instant case is void having been issued without LOA. (Cebu Mitsumi, Inc. vs. Commissioner of Internal Revenue, CTA Case No. 8531, May 21, 2015)