Brian Wharton, the chief detective of a small police force in East Texas, had seen his share of tragedies on the job, but he had never handled a case like Robert Roberson’s : In January 2002, Roberson, a 35-year-old single father, arrived at the emergency room with his 2-year-old, Nikki, limp and bundled in a blanket.

Roberson said the girl had fallen from bed overnight, but when nurses and doctors evaluated her severe head injuries, they grew suspicious. Wharton led the investigation.

Robert Roberson with his daughter Nikki. (Courtesy Roberson family)