D.C. Mun. Regs. tit. 3, r. 3-1003
In order for an initiative or referendum measure to obtain ballot access, it must be supported by a petition filed with the Board that contains the valid signatures of at least five percent (5%) of the registered qualified electors of the District of Columbia, provided that the total number of signatures submitted shall include at least five percent (5%) of the registered qualified electors in at least five (5) of the eight (8) election wards.
The maximum number of signatures that the Board will accept for filing is two (2) times the minimum number of signatures as required by this section. Working from the first page of a petition that has been serially numbered pursuant to Subsection 1005.2 of this chapter, the Board shall only accept for filing the maximum number of signatures that may be filed pursuant to this section.
The Board shall use the latest official end-of-month count of registered qualified electors published in the District of Columbia Register that was made at least thirty (30) days prior to submission of the signatures for the particular initiative or referendum measure to determine the minimum number of signatures required for ballot access. Any subsequent changes in the District-wide or ward voter counts, including changes caused by any redistricting, shall not be grounds for challenging the number of signatures needed on a petition as calculated based on five percent (5%) of such published end-of-month count.
D.C. Mun. Regs. tit. 3, r. 3-1003