70.21—Canvass for taxable persons and objects.
Each appropriate TTB officer shall, to the extent deemed practicable, cause officers or employees under the appropriate TTB officer's supervision and control to proceed, from time to time, and inquire after and concerning all persons therein who may be liable to pay any tax, imposed under provisions of 26 U.S.C. enforced and administered by the Bureau, and all persons owning or having the care and management of any objects with respect to which such tax is imposed.