A Utah grief author's murder trial. Eyewitness drama in Florida. Plus, Nancy Guthrie and Olivia Lone Bear.

The highly anticipated trial of Utah mom-of-three Kouri Richins is finally underway. Prosecutors say she poisoned her husband with fentanyl. In Miami, jurors watch video testimony of an eyewitness who may have seen the killer of football player Bryan Pata. In Dateline Round Up, Nick Reiner enters a…