28 U.S.C. § 1743

Demand on postmaster

The certificate of the Postmaster General or the Government Accountability Office of the mailing to a postmaster of a statement of his account and that payment of the balance stated has not been received shall be sufficient evidence of a demand notwithstanding any allowances or credits subsequently made. A copy of such statement shall be attached to the certificate.

( June 25, 1948, ch. 646 , 62 Stat. 948 ; Pub. L. 108–271, § 8(b) , July 7, 2004 , 118 Stat. 814 .)