Defense lawyers for the man charged in the killing of University of Iowa student Mollie Tibbetts are asking for his trial to be delayed. Lawyers for Cristhian Bahena Rivera say they need to delay the Feb. 4 trial date so they have time to appeal a judge’s ruling that allowed key evidence to be used against their client. The Iowa Supreme Court will consider whether to take the appeal before trial. Rivera’s lawyers also say they want to depose several individuals recently added to the prosecution’s witness list, including Tibbetts’ boyfriend at the time of her July 2018 disappearance.