Highway shootings are on the rise in some states — and notoriously difficult to solve

On the morning of Nov. 18, Amani Morris was headed to a new job at a child care call center in the San Francisco Bay Area when her phone rang. It was her mother FaceTiming from Atlanta. 

Alicia Benton wanted to talk, as she often did, to her two grandchildren. The boys, then ages 5 and 3, were in the car, along with Morris’ fiancé, who was driving.

Moments into the call, Morris, 29, interrupted and told her mother that she loved her and that she’d speak to her after...