by John Marshall Harlan

“ They insisted that the contract sued on was in violation of that statute; and that they and the estate of Nutt were protected by its provisions against any judgment whatever in favor of the plaintiff. In every substantial sense, therefore, they asserted a right and immunity under a statute of the United States, and such right and immunity was denied to them by the supreme court of Mississippi. ”

“ All transfers and assignments made of any claim upon the United States, or of any part or share thereof, or interest therein, whether absolute or conditional, and whatever may be the consideration therefor, and all powers of attorney, orders, or other authorities for receiving payment of any such claim, or of any part or share thereof, shall be absolutely null and void uniess they are freely made and executed in the presence of at least two attesting witnesses, after the allowance of such a claim, the ascertainment of the amount due, and the issuing of a warrant for the payment thereof. ”

“ A party who insists that a judgment cannot be rendered against him consistently with the statutes of the United States may be fairly held, within the meaning of § 709, to assert a right and immunity under such statutes, although the statutes may not give the party himself a personal or affirmative right that could be enforced by direct suit against his adversary. ”