Not an accusation theory, but a theory to disprove every other theory that Patrick Jane is Red John.

http://www.youtube.com/watch?v=fgvXfZK9dnw

This video shows Rosalind speaking to Jane whilst RJ is there in episode 13, "Red is the new black", season 4. 
Possible argument to this is that she initially said "Roy CAME to see me" suggesting she lied about him being there. I don't think we should read into every single word though. I personally think it's Brett Stiles. 
I mean who's a better Red John than Alex DeLarge, the classical music loving, original sociopath, all 'cured' and grown up!!