My prime suspect is Dean Harkin
1) First lets look at his name and the meaning. As we know this show there alot of cryptic clues that we have to decipher.
*Dean (Definition of *) - The head of a faculty. The senior member, of any group, organization.
A man who is the senior member of a group
(Red John as alot of followers and clearly he is the Head and Senior member of this group)
**Harkin (Definition of **) - Irish and Gaelic origin, and the meaning of Harkin is "Dark Red".
Irish: Anglicized form of Gaelic Ó hEarcáin
‘descendant of Earcán’, a byname or personal name formed
from a diminutive of earc ‘Red’, ‘Bloody'.
2) In Episode 11 Season1, when Jared Renfrew writes on the wall "He is Mar" - could he have instead meant to have written "He is Har" as in "He is Harkin" (Just a thought)
3) Rosalind Harker - again a play on names - both Dean and Rosalind have very similiar surnames Harker and Harken.
RJ and Rosalind were lovers and this could be a clue that links them together.
4) He as powerful friends in the FBI - in the episode Code Red he states
"I'll call my friends at the FBI, get them to take over from you. In fact, I will do that."
5) Hes description - He as Red hair and fits the description of what Rosalind describes.
6) He's probably married (has a wedding ring at finger), and Patrick Jane describes him as one who scares people, and an irksome man.
