D.C. Code § 16-4603.06
Enforcement of registered determination.
(a) A court of the District may grant any relief normally available under the law of the District to enforce a registered child-custody determination made by a court of another state.
(b) A court of the District shall recognize and enforce, but may not modify, except in accordance with subchapter II of this chapter , a registered child-custody determination of a court of another state.