Lab analysis continues on what the sheriff's office says is "biological evidence" found at Nancy Guthrie's home. CNN's Randi Kaye looks at other cases and how sometimes the DNA implicates the innocent. | Anderson Cooper 360

While reporting on Hurricane Katrina in 2005, CNN’s Anderson Cooper witnessed a dead person atop a vehicle on a flooded street in New Orleans. That person turned out to be Jerry Peters. Cooper visits with Peters’ nephew Pastor Jerry Darby in this deeply emotional story. | Anderson Cooper 360