This section is from the book "The Constitutional Law Of The United States", by Westel Woodbury Willoughby. Also available from Amazon: Constitutional Law.
In this case the alien was domiciled in the United States, but it would not appear that domiciliation is necessary as a basis for holding the alien liable for treason, if the act of treason be committed within the territorial jurisdiction of the United States.
92 Carlisle v. United States, 16 Wall. 147; 21 L. ed. 426; Radich v. Hutchins, 95 U. S. 210; 24 L. ed. 409.
93 95 U. S. 210; 24 L. ed. 409.
If the act be committed by the alien outside of such jurisdiction, no treason can be alleged.94