“ A decree to that effect would operate directly upon him, and would not contravene that provision of the statute prohibiting a court of the United States from granting a writ of injunction to stay proceedings in a state court. It would simply take from him the benefit of judgments obtained by fraud.' And if a United States court can enjoin a plaintiff from using a judgment, proved to be fraudulent, it can likewise enjoin him from using a judgment absolutely void for want of service. ”

“ A judgment might be obtained without the least knowledge of the person sued. Under the phrasing of the statute, the duty of the officer begins and ends in his office. If such a judgment were rendered, it could receive no recognition whatever at the place of the domicil. When a petition cannot legally be served on a defendant, the court can exercise no jurisdiction over him. ”

“ If that be so, the United States courts, by virtue of their general equity powers, had jurisdiction to enjoin the plaintiff from enforcing a judgment thus doubly void. For even where there has been process and service, if the court 'finds that the parties have been guilty of fraud in obtaining a judgment . . . it will deprive them of the benefit of it.' McDaniel v. Traylor, 196 U.S. 415, 423, 49 L. ed. 533, 537, 25 Sup. Ct. Rep. 369. Much more so will equity enjoin parties from enforcing those obtained without service. ”