An interesting question, especially given 17 NAVAJO CODE § 203, which reads:
The Navajo Nation Courts shall have jurisdiction over any person who commits an offense by his or her own conduct if the conduct constituting any element of the offense or a result of such conduct occurs within the territorial jurisdiction of the Navajo Nation Courts as defined in 7 N.N.C. § 254, or such other dependent Indian communities as may hereafter be determined to be under the jurisdiction of the Navajo Nation and the Courts of the Navajo Nation. The Navajo Nation Courts shall also have jurisdiction over any member of the Navajo Nation who commits an offense against any other member of the Navajo Nation wherever the conduct which constitutes the offense occurs.
For more detail on the extra-territorial application of federal criminal law as a possible analog, see this report from the Congressional Research Service.
Turtle Talk 