Welcome Olivia.
There are so many reasons why everything points to only one perpetrator of this crime.
SimonSays asked once is there a book out yet. Not in a lighthearted fashion, I wrote a quick synopsis or short unfinished story of the case for him.
This was copied to General Discussion #7 by LaurieJ, post #11 ont his discussion.
http://websleuths.com/forums/showthread.php?t=31287
It doesn't go into all the twists and turns of the case, but if like Simon you are looking for a shortend condensed version, and I do mean this seriously, this hurt me to type, and hurt me more to read it in this fashion, because Janet is not just a girl, she was a beautiful woman that was brutally, senslessly murdered and taken away from her child and her family and her friends, and she had so much to offer the world because of the sickness, and evilness of P.Ness.
Take care, and welcome to the forum. Jump in anytime.