My theory is that Bob Kirkland is Red John.  I think that we have been seeing a combination of Michael and Bob throughout the past two seasons, and it was Michael that was murdered by Reede Smith.  The story told to Patrick about the Kirkland's childhood was true, except the brothers name's were switched.  Michael worked his way through the ranks of Homeland Security under his brother's identity, and occasionally Bob (Red John) appears as himself in order to cover his tracks without Michael's knowledge.

Bruno Heller stated that Red John is 100% on the List of Seven, and we don't know for certain that was Bob that was killed, not Michael. 

I know a lot of people won't like this theory but even if Kirkland isn't red john I think he pretended to be in one episode when we seen the reflection on the computer for Dr. Joe n.h it is his face and you can tell by the way he blinks some people have a faster more distinctive blink and if you watch it then watch no. Kirkland scenes the face is the same and the blinking is the same so I'm not saying he is red john but maybe he was trying to help Patrick without exposing himself because he was getting all the info Patrick had so why not let him follow the leads and he would have access to the doj system.

what did Bob Kirkland say to PJ when he was being taken away? you will take this to the end right? or something to that effect. the fact that when PJ reveals the list it has pictures and not just names should mean something IMO. In the episode RED DAWN when they show how PJ started working at CBI BK was in the background and through Alexa made a deal to get information about RJ case. Does anyone know the middle name of BK? if it starts with J then he is RJK.
I still feel there will be some twist involving BK and MK..

Has anyone thought about the end? We know Jane ends up in South America - on the run. But I'm very curious as to the Jane/red John showdown in this 'beautiful park' in the daylight.

Once Red John exposes himself to Jane (whilst law enforcement, the media etc all hunt down the 'false' Red John that Jane has 'given them) and they meet, and talk - this is what I'm looking forward to.

What would Red John's worst nightmare be as he is dying? Knowing that someone else (Bertram/Smith whoever) is going to get all the 'credit' for the Red John crimes? Knowing that someone he thinks of as INFERIOR is going to be prosecuted for his crimes of which he is in fact terribly proud.
Imagine being Red John and Jane tells you as you are dying, that the world will never know who you really are. And that the world will think that a 'dumb foot soldier from TT' is Red John. A person dumb enough to get caught and prosecuted.......
This will infuriate Red John beyond belief I reckon - and Jane once more, know this.

Which is why Red John will die knowing some 'idiot suspect selected by Patrick Jane ' is forever going to be known as Red John.
THIS is Jane's final play and it's a checkmate. Red John dies unknown, without credit  and with a public who think he's currently a fat cop (Reede Smith) sitting in a holding cell.

To fit into the above; this is why I believe the name Patrick will give to the press as Red John will be Reede Smith's - because he is an evil man, and deserves to spend his life behind bars (but for being a corrupt cop, TT man and murderer)

Patrick killing two birds with one stone. 1) Insulting Red John in his death - because he will die knowing Reede Smith is awaiting trial for Red John/TT crimes; which honestly? Could there be a greater insult to a sociopath like RJ?
2) He gets rid of one evil man from law enforcement - Reede.

If this theory is correct - we can all understand why a 'joke' like Reede Smith was a 'suspect'. Jane put him there because he knew Smith would be the greatest insult to the ego of RJ. RJ is dying and the last thing he sees is Jane, and the last think he thinks is burly, hurly Reede Smith (imperfection at it's best) will be known as Red John for the rest of time.

Patrick - 1
Red John and his ego - 0 (every sociopath has a weakness.....)

So how to wrap this neatly? Bob Kirkland is already 'dead'. Jane can kill him in cold blood, get rid of the body and keep quiet. Which is what I believe happens.
The CBI team will not know Kirkland is the 'real' Red John - no-one will, bar Patrick Jane.

Jane goes on the run, not for murdering 'Red John' but because he probably does something else reckless.

Jane get's away with murder. Which makes for an interesting episode after the 'Red John' one.

Long post again - sorry.

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Reede Smith CANNOT be Red John, because one thing we know for sure is that Red John and Michael Kirkland knew each other. Therefore, it is highly doubtful that Red John would have killed Bob without saying something about his brother. Think about it, the one thing Bob was after was Red John, and for Red John to not even hint at knowing his brother and relish in his victory would be very uncharacteristic.

Also, it appears that someone on Jane's inner circle has turned, and Jane knows about it. Because Jane is feeding the team more details than ever, like the tattoo thing. If Jane truly believed that Red John had a tattoo, he would have never spilled. Think about it, has he suddenly become a team player on the biggest case of his life? Not a chance! Did the team have to know about the tattoo for them to go along with the plan? No, Lisbon was ready to gather them up right after she heard about the list of seven. He planted a false idea in the team's head because he knew it would be relayed by to Red John. There is definitely a rat!

There are three options on who the rat is:

1. Lisbon unknowingly is communicating with Red John because he hypnotized her? Perhaps the nurse activated her with the name Carmen Lee.

2. Van Pelt could have turned, which is a popular theory. However, I'm inclined to believe the Craig situation changed her, and she is has a much stronger threshold now.

3. Rigsby would be the biggest twist of all, because no one would ever expect an "oaf" like him to be in allegiance with Red John. And no one would expect Grace to be duped yet again into pairing up with a man with ulterior motives.

I said this before, but remember Jane never told them that Michael Kirkland was Bob Kirkland's twin. To me the fact that it is left unsaid is because he believes someone in that group cannot be trusted. Furthermore, Jane's silence on the Michael Kirkland matter could give us a big clue about Red John. I have thought maybe Michael Kirkland is Red John, but who knows? 

There are a lot of loose ends that need to be tied up, though, that is for sure!

To add to my earlier theory, just to clarify.

Who says Bob Kirkland was 'really' hunting Red John? In the same way Jane mindfucks red John, Red John mindfucks Jane.
If Bob was really hunting Red John - the murder of Jason Lennon would not have taken place - simple as that. All Bob says to Lennon is "your MIND is clear - (classic hypnotism) - and then "have you seen me before". Lennon's memory has been 'washed' and then he is killed.
Still not sure which 'Bob's' we saw were Michael, and which were Bob - but guaranteed something is going to evolve from this.

Bob (Red John) knew Patrick Jane has been getting closer and closer from the minute Jane met Lorelei Martins. He needed to provide himself with some 'cover' and a legitimate excuse to find out just how close Jane was getting. What better way than to 'be hunting for Red John himself, due to a brother that been led astray - yeah right - lead astray by Bob more likely' and what better way to 'disguise' this?

Bob's big mindfuck of Jane: 'giving him the brother story' (which probably has some truth in it somewhere, but involving the 2 twins together: stronger twin saving the weaker - reading each other's minds - fighting the evil father etc) and hoping Jane believed it.
Kirkland has been playing TT and Jane in the same way Jane plays Red John: and in the process spinning a wonderful web in which he can escape (death to Michael) and hopefully disappear.
The failed bomb put an end to that.....

Kevin Corrigan would be a perfect red John. And boy, he would pull of a final showdown with Jane something special.

(Really hoping it's him - simply for the Corrigan performance)

Sorry for the long post. But I believe this is how it's going to go down.

Patrick Jane is going to play the final game in the press conference in 'The Great Red Dragon'. The spoilers state that he and Lisbon will reveal the name of 'Red John'. Lisbon will believe this name is true.

Patrick is however setting up the final showdown, making sure the media, ALL law enforcement and his own team are sent on a chase after Betram or Smith (whichever one he reveals as his 'false' Red John in the press conference). This allows Jane the space, time and opportunity to draw the real Red John into the open: ending in Red John's death in a park - eventually.

Whilst lot's of excitement will be created as the police and media go beserk and hunt for 'Red John' (Bertram or Smith - whichever name Jane feeds them....), the real Red John will be drawn out in a desperate act to contact Jane - simply to tell him 'he has the wrong guy'. We know Jane has fooled Red John once (the drinking and breakdown), he can and WILL do it again by giving the false name 'very convincingly'. The real Red John, (even though he tried to kill Jane with the bomb...) won't be able to resist contacting Jane about some other 'person' getting credit for his work.
We know there is nothing Red John hates more. And if he is made to believe that Jane REALLY believes Bertram or Smith IS Red John - well, he will risk it all to show Jane otherwise.

By now, Red John has nothing to lose, neither does Jane. His attempt to kill Jane failed, and he's now planning his 'escape' into society and normality. The ONLY thing that will draw him out to Jane is when his ego won't allow him to accept that his friend/foe Jane is crediting someone else as Red John. And Jane: KNOWS THIS.

Jane knows Red John (the real one....) will only come out in those circumstances. His ego will take over and force him to reach out to Jane.

The scene with the final 5 suspects and the tattoo hocus pocus - for Jane it's been nothing more than an elaborate and convincing plan to 'give someone else credit for being Red John', making the real Red John believe this and thereby forcing his ego to expose himself, finally.

Enter Bob Kirkland once more. His hair has now been dyed (red probably) - ok, wild guessing here, but it sounds fitting.

Final showdown. Fight to the death.