Pub. L. 110-161, div. E, tit. V, sec. 516

Sec. 516. None of the funds appropriated to the United States Secret Service by this Act or by previous appropriations Acts may be made available for the protection of the head of a Federal agency other than the Secretary of Homeland Security: Provided, That the Director of the United States Secret Service may enter into an agreement to perform such service on a fully reimbursable basis.