D.C. Code § 16-577
The per centum limitations prescribed by section 16-572 do not apply in the case of execution upon a judgment, order, or decree of any court of the District of Columbia for the payment of any sum for the support or maintenance of a person's spouse or former spouse, domestic partner or former domestic partner, or children, and any such execution, judgment, order, or decree shall, in the discretion of the court, have priority over any other execution which is subject to the provisions of this subchapter. In the case of execution upon such a judgment, order, or decree for the payment of such sum for support or maintenance, the limitation shall be 50 per centum of the gross wages due or to become due to any such person for the pay period or periods ending in any calendar month, except that a notice or order to withhold issued pursuant to subchapter I of Chapter 2 of Title 46 shall have priority over any other legal process and shall be subject to the limitations stated in section 303(b) of the Consumer Credit Protection Act, approved May 29, 1968 (82 Stat. 163; 15 U.S.C. § 1673(b).
D.C. Code § 16-577