Before going on a hike in Oregon in 2009, 23-year-old Rhonda Casto joked to her family that her boyfriend was either going to give her a ring, or throw her off a cliff. A few hours later, she fell to her death from the Eagle Creek Trail. Her boyfriend, Stephen Nichols, told police she had slipped. But investigators soon discovered that just months earlier, he had raised the life insurance on her to $1 million. He had also been secretly sleeping with her younger sister, who was just 16. Rhonda's family was sure her death was no accident. Six years later, Nichols was arrested and charged with murder. But the case quickly fell apart. A detective had destroyed the photos from the crime scene and the autopsy, and the court refused to allow his police interview as evidence. In the end, Nichols pleaded guilty to much smaller charges, criminally negligent homicide and coercion. He was sentenced to 19 months in jail, but because he'd already served that time while awaiting trial, he was simply released and placed on three years of supervision.