D.C. Code § 50-710
The choice of clean-fuel vehicles and clean fuels shall be made by the covered fleet operators subject to the requirements of this chapter.
Mar. 8, 1991, D.C. Law 8-243, § 11
as added Mar. 14, 1995, D.C. Law 10-201, § 2(g), 41 DCR 7178
1981 Ed., § 40-2010.