D.C. Code § 47-403

The cashier (in the Collector’s office) shall, in the necessary absence or inability of the Collector from any cause, perform his duties without any additional compensation; and the Collector may require the said cashier to give bond for the faithful performance of such duties during the absence or inability of the Collector; but the Collector shall in every respect be responsible, as now provided by law, to the United States, the District of Columbia, and to individuals, as the case may be, for all moneys collected.