On the venue issue, Mr. McElroy was alleged to have moved from Sedgwick County to California. The KSC also held that venue was not proper in Sedgwick County because the elements of failure to register include a change of address and failure to notify the KBI. Shawnee County (where the KBI repository is located) would clearly have venue with regard to failure to notify the KBI. But the KSC held that moving from a county is only a precursor to the other element: a change of address. Because no change of address occurred in Kansas, venue in Sedgwick County was inappropriate.
There is some pretty good language in McElroy on venue issues as well:
We note that the defendant's failure to object to venue at trial is irrelevant because venue is a matter of jurisdiction. Lack of jurisdiction is not a waivable defense and may be raised for the first time on appeal. Although venue is a question of fact to be determined by the jury, the existence of jurisdiction is a question of law over which this court's scope of review is unlimited. To the extent this case requires statutory interpretation, such interpretation also raises issues of law subject to de novo review on appeal. [citations omitted.]