D.C. Code § 42-1107
For the purpose of proper administration of this chapter and to prevent evasion of the tax hereby imposed, it shall be presumed that all deeds are taxable and the burden shall be upon the taxpayer to show that a deed is exempt from tax.
Mar. 2, 1962, 76 Stat. 13, Pub. L. 87-408, title III, § 307
1973 Ed., § 45-727.
1981 Ed., § 45-927.