In U.S. v. Dumont, the 11th Circuit held that the defendant's alleged interstate travel during the gap period did not create an Ex Post Facto Clause problem. This has been the majority approach of district courts, so the result is not at all surprising. However, because this opinion was by a federal appellate court, it is obviously more significant. In contrast to the holdings of many district courts, though, the reasoning in the opinion was "odd" at times. From the opinion:
This Court recently addressed a timing issue involving a prosecution under SORNA in United States v. Madera, 528 F.3d 852 (11th Cir. 2008), which guides the resolution of Dumont’s appeal. Madera was convicted of a prior sex offense in 2005, and moved from New York to Florida in 2006, all before SORNA’s enactment. Id. at 854. Madera failed to register in Florida upon his arrival, and was arrested and charged in 2006 for violating § 2250. Id. Before the Attorney General ever issued his interim retroactivity ruling, the district court conducted its own retroactivity analysis and declared SORNA retroactively applicable to Madera. Id. at 856.... Madera’s case was “unique” because the district court “clearly erred by usurping the role of the Attorney General in presumptively determining SORNA’s retroactive application.....” Here, unlike Madera, Dumont was prosecuted after the Attorney General’s retroactivity determination, and his superseding indictment covered the period “from in or about February 15, 2007, continuing through on or about May 16, 2007.” As noted in Madera, “[i]t is now clear . . . SORNA is to be retroactively applied.” Id. at 857. Accordingly, Dumont’s obligation to register arose on February 28, 2007, the date of the Attorney General’s retroactivity determination, and Dumont had three business days–through March 5, 2007–to fulfill this duty. See 28 C.F.R. § 72.3.; 18 U.S.C. § 2250; 42 U.S.C. § 16913(c). Dumont failed to do so, and as of March 6, 2007, Dumont was in violation of § 2250....
All of that reasoning is fine and dandy as to the statutory interpretation issue. You can disagree with the distinction, but it is at least coherent. However, it should have no bearing on whether there was an Ex Post Facto Clause violation. The court didn't go through the normal required analysis (retrospectivity, punitive in intent or so punitive in effects) at all. Instead, the court cited an old draft registration case which only related to a statute of limitations issue (which the 11th Circuit even acknowledged). It is almost as if the court forgot to analyze the Ex Post Facto Clause part of the defendant's claim.
Likewise, § 2250 does not punish a sex offender for merely traveling in interstate or foreign commerce. Rather, § 2250 criminalizes a sex offender’s failure to register after traveling in interstate or foreign commerce, and the “travels” language provides a jurisdictional basis. Accordingly, the fact that Dumont’s travel to Florida occurred prior to the retroactivity determination does not preclude his prosecution under SORNA.