It is clear since Hathorne, 459 S.W.2d 826 that a judge is not disqualified from presiding over a trial where he prosceuted the defendant for a prior offense being used to enhance the punishment. Is the rule the same with respect to a prior conviction that is an element of the offense on trial (e.g., unlawful possession of firearm or failure to comply with sex offender registration requirements)? I have been unable to find a case on this point. I realize that Ex parte Richardson, 201 S.W.3d 712 lessens any cause for concern, but I want to be sure recusal is not called for.