(a) This Code applies in all places. It also applies to all persons otherwise subject to this Code while they are serving outside the Territory of Guam, and while they are going to and returning from such service outside the Territory of Guam, in the same manner and to the same extent as if they were serving inside the Territory of Guam.

(b) A court-martial, court of inquiry, a military commission, or a provost court may be convened and held in units of the territorial military forces while those units are serving outside the boundaries of Guam, with the same jurisdiction and power as to persons subject to this code as if the proceedings were held inside the boundaries of Guam, and offenses committed outside the territory may be tried and punished either inside or outside the Territory of Guam.

SOURCE: UCMJ ARTICLE 5.