Section 11National Internal Revenue Code of 1997 (Republic Act No. 8424), Sec. 11

Duties of Revenue District Officers and Other Internal Revenue Officers. - It shall be the duty of every Revenue District Officer or other internal revenue officers and employees to ensure that all laws, and rules and regulations affecting national internal revenue are faithfully executed and complied with, and to aid in the prevention, detection and punishment of frauds of delinquencies in connection therewith.

It shall be the duty of every Revenue District Officer to examine the efficiency of all officers and employees of the Bureau of Internal Revenue under his supervision, and to report in writing to the Commissioner, through the Regional Director, any neglect of duty, incompetency, delinquency, or malfeasance in office of any internal revenue officer of which he may obtain knowledge, with a statement of all the facts and any evidence sustaining each case.