Evidence.
The window, the DNA, the lack of motive for the parents to kill their daughter, etc. etc.
Now care to share what evidence you have that they are guilty?
Huh? You have to do more than list a few items without explanation. Let's start with the DNA. How does discovery of skin-cell DNA on the underwear EXCLUDE the Ramseys? Did you know that the police tested five unopened packages of Jon Benet's type of underwear (from the factory) and found male DNA on three of them? Do you have any idea how many people touched her underwear after her father, mother, and neighbors contaminated the scene?