Here is the opinion in U.S. v. Begay.
Defendants argue that SORNA did not require them toupdate their registration with the State of Arizona while they were residing in the Navajo Nation, and that they could notupdate their registration with the Navajo Nation because it had not yet established a sex offender registry. Based on thesepremises, they invoke SORNA’s affirmative defense, which applies when “uncontrollable circumstances prevent[ ] theindividual from complying” with SORNA. 18 U.S.C.§ 2250(b)(1). Alternatively, they argue that if SORNA did require them to update their registration with Arizona, SORNA violates the Due Process Clause of the Fifth Amendment and the Ex Post Facto Clause.We hold that SORNA required Defendants to update theirregistration with Arizona, and because nothing prevented them from doing so, no “uncontrollable circumstances prevented [them] from complying” with SORNA. Moreover, wehold that this application of SORNA violates neither the Due Process Clause nor the Ex Post Facto Clause. Thus, we affirmthe district court’s denial of Defendants’ motions to dismiss their indictments.