Theory---he IS SHOWN TO STEAL JANES WORK
              He kill the only witness in coma nd asks him"do you know me"

Psychological aspect , Red John way of killing points to a inferiority
complex towards women , but the sign of the wall and specially the
fact his associates would die for him proves that underneath this he's a
confident , charming and imposing person .
 The fact that Red John has
so many connections and resources  points to a man in high position
,not forensic worker by the way he kills it's clear that he has
knowledge of the field ,it's hard for someone from outside to become so
good because it's a thing that needs practicing , you can get all the
knowledge about martial arts ,but it's different from when you are in a
fight.
That's why i don't like the idea of Bret Stiles , but on that theory
Patrick wouldn't be a good detective so i need to take an other angle
he's manipulative kind of character, not the strong imposing character
Profile of Red John .And at one moment it was clear that he had the
ability to make pretty women fell in love with him ,clearly no
inferiority problems towards women , that's why he's out in my view  2
Partridge Brett okey , I get the the idea that he has the same name
as Stiles ,but i haven't seen any link
that the 2 were related ,and personal you couldn't pick a more
antipathetic Red John then Partridge he's just a forensics ,hard for
him to get the resources Red John would have ,and high level connection,
no showmanship that was a strong personality trait of RJ , He seems
way to shy ,i will agree he's strange but that could mean also that he
likes his job , and he's job being investigating dead people i get why
it looks weird when he's passionate about it. But he's not necessary a killer . Why i have ruled
him out was because of a talk Patrick had when Red John said to him
that he's getting too old for this ... and Patrick should move on , find
a new life. I Partridge it's the Young's some people had here pointed
out he could be to young to even committed the first murders but i
don't guess . What i think by what i could deduce is that Bob Kirkland
is the one .
1 Strong imposing Character ,
 2 awkward   around women ,when
he took the dinner with Lisbon
,3 high position Homeland would provide

4 and most important Red John pretended to  read Jane's mind when he
came with the list ...Now Patrick said numerous times that psychics
don't exist there just tricks , Kirkland got in Jane's room , He got the
information and made the same deductions Patrick made ,that was he's
trick , that's why i think is him .

I just want to point out that in season five finale the rj accomplice told Jane she knew rj. Then he let her be in cop car with only driver and she wasn't throughly searched since she had pill and killed herself. This means Jane must already know exactly who pj is or else he would not have let this happen. Also Lisbons broken wrist was very weird.

http://insidetv.ew.com/2013/05/06/mentalist-finale-season-6-red-john-list/This is a link to an interview of Bruno Heller about the list of the 7 possible  RJ. It helps to already rule out PJ as RJ and the possible idea that the list is not reliable :)

Personally however I think Bob Kirkland is either RJ or his accomplice. If you guys remember from the episode of PJ's first day at FBI, it ends with the FBI attorney (the mean red head) asking Bertram for information on RJ on the phone. Then she says "it's done" to a Kirkland who was in the same car as her. Maybe it is her ... who knows... since apparently being a red head makes you Red John (Van Pelt reference) 

Why ? Because there we're two persons that knew Jane's suspect list .And one of them was Jane . That mind reading trick was nice ,coming up with the exact suspect list as jane  , impressive , " but mind reading doesn't exist , it's just a trick " . That's why i think is Kirkland

I am not sure who Red John could be, but thinking about a comment I recently read, I had a crazy idea come up:
when Kirkland asks Lennon, if he recognizes him, could it be that he had plastic surgery? Lennon knew the old RJ face and if he wouldn't recognize him now, RJ can be sure that his disguise ist perfect.

I don't like the idea too much, but it the only way that Kirklands question makes sense to me so far.

So, if Kirkland had plastic surgery, how has he been looking before? Compare Kirkland to Walter Mashburn... face would be possible, the only thing is that Walter is taller than RK... that doesn't fit. But Teresas role would be explained. RK has been to PJ's room, so that could hint to the LM video.
So, what do you think?

I always thought that RK is NOT RJ, bur the more I think about his behaviour, the more plausible it seems to me.
I still like the idea of Walter being RJ, it would be the most interresting character to be RJ as PJ has a good connection to WM and also WM has a crush on Teresa.

All the other characters would be disappointing to me. 
Partridge is a possibility, too. He's has been one of my main suspects all the time
Stiles - I don't think so
Reede Smith - I don't think so
Gale Betram - possible, but I don't think so.
MCAllister  maybe, strange character...
Ray Haffner - I reall don't think it is him

In episode 8, season 2, after Virgil lost it a bit towards the reporters interviewing after four of his men got killed, did we catch our first glimpse of bob Kirkland? You can see someone getting out of a black vehicle, he really looks like BK. suddenly, Virgil decides to retire. Whether or not bk is actually red John is yet to be seen, but we know he's involved heavily.