d. Letter of Authority

Requisite Authority of Tax Examiners and Due Process in Assessments

Issues regarding whether a tax assessment was made with the requisite legal authority or due process notice are inextricably intertwined with the validity and enforceability of the assessment¹. As held in CIR v. Standard Insurance Co., Inc., G.R. No. 259729, 17 November 2025, the Court of Tax Appeals may properly resolve challenges pertaining to an examiner's authority¹. In doing so, courts are not restricted by the blind spots of the parties and are empowered to consider fundamental legal issues that are apparent from the record¹.

Tax collection must strictly adhere to lawful procedure and basic fairness¹. Accordingly, the State must exercise its taxing power with reasonable dispatch, as inordinate delays in resolving protests may offend due process and, where the applicable prescriptive period has run, warrant cancellation of the assessment¹.