The show has a lot of Spanish references He is Mar (El es mar)
Red tattoo -  La vida loca posted by another member.
It all points to Ardiles isn't he Hispanic? RJ is Oscar! DUM DUM DAH

Last episode of mentalist cleared much of things than it should be i beleive :)
3 dots tattoo is an interesting field of evidence.
im going to start with 5 dots though; 5 dots means many things in many culture.
it could mean 5 things to do with women, i was surrounded with 4 cops, ill never forget prison etc.
only thing that is absolutely common about 5 dots is it's all about prison.
Just like 5 dots, 3 dots has an interesting facts about prison either but it also represents latino origin.
A man who's probably born and raised in south america, who maybe in prison there before could make red john's possible profile. And most clearly its not the first time the serie is giving hidden clues about red john in latin languages such as names apeearing out of nowhere like Carmen Lee. 

So I suggest Red John is Oscar Ardilles who's the only  Latino Character.

I have narrowed my list to three suspects.  Let's keep in mind that Red John is probably in his 40's.  Red John is also under 6'0.  Red John was seen in season 3 finale. If you look at Red John he is not a heavy set man by any means.  He looks to be thin. 

Ron.  Ron could be Red John, but I just don't see him being Red John.  Ron could be the sleeper.  My gut tells me it's someone else.

Bob Kirkland.  Kirkland came out of the blue.  I don't see them having Kirkland as Red Joe.  There's signs that point to him being Red John, but Heller already knew who Red John was when they started it all.

Oscar Ardiles.  He would be the perfect Red John.  He could easily get a bunch of misfits to do his dirty work to get them out of jail time.  He knows the whos who of the CBI,FBI, ext.  And, as for a DA, and all the cases the CBI cracks, you never see the guy.  He has been there since the beginning.  He is a soft spoken guy, he's very smart, and we know nothing about his history. 

First time commenting on here.  Love the site.  I think Red John is D.A. Oscar Ardiles.  As Heller has said the list is real, but doesn't say for sure Red John is on that list.  Why couldn't it be the D.A.?  He's not a main character, and we really don't know his history.  He could be the perfect Red John.

Red John is more than one person. All of the thought and dedication takes more than one man. Red John seems to be different here and there which throws you off of his scent. Besides it would be too anticlimactic if it ended the way it is going. This would be a nice twist

SparkedIntoLife > Actually, that's funny ! I made the whole same investigation as you did there ! I swear !
But there is one thing, and only one, that I found different : Osvaldo Ardiles isn't under 5'5 foot tall. Actually he is ... 5.9 foot tall. Yeah, you're not mistaken, and that fact changes a lot of consequences.

Ardiles has the average build of Red John. He has short, straight hair like Rosalind said.

Here are ALL the criterias shown all along the show (I think I didn't miss anything, and no judgement in those) :

Shown on the screen : Red John drinks tea, and holds his cup of tea with the left hand. He is "sophisticated".

Haley said : Red John is a white guy, had a baseball cap and and an odd voice.

Rosalind Harker : Red John is just under 6 foot tall (fits perfectly Ardiles), average build, short and straight hair, gentle voice. He smelt earth most of the time and liked to listen to her playing piano.

Patrick Jane : Red John considers himself as a showman, an artist. He has a strong sense of theater. He doesn't like losing, nor when someone is mocking him. He is meticulous and don't make mistakes. If you have a clue, it's because he gave it to you intentionally.

Lorelei Martins : Red John is a manipulator and charismatic (which would kind of eliminate Bret Partridge of the suspects for me ... well).

Red John himself : Has a friend in the FBI (didn't say he was himself in the FBI). Hates poor imitations of his work. Isn't religious.

Following those criterias, from the 30 suspects list, 6 only may stay suspects :
Paul Fricke (I didn't see you mention him at all) ; Robert Kirkland ; Dr. Royston Daniel ; Ray Faffner (average height) ; Richard Haibach (same here) ; Osvaldo Ardiles.

Why did I rule out Bret Partridge, even though he fits almost all the criterias ? Because he isn't charismatic at all (unlike the description of Red John by his fidels), doesn't seem to be hard to read for Jane, likes too much his work, is an evident suspect that the producers would like us to believe of, doesn't leave the memory of someone powerful, someone that terrifies us, someone that we would fear till the end.

I don't think it would be a good thing if we remembered of Red John as someone who has already lost to anyone and needed help before in the show. For that reason, I guess we can rule out Paul Fricke (who needs the help and money of women to live) ;
Dr. Royston Daniel (was going to be killed by some average woman, couldn't expect that Jane would come to help and, when it turned out they didn't stand a chance, it was Jane who found how to wake up Rigsby, not Royston Daniel. Would he really accept the fact that he lost pitifully against Jane already in his chosen field ? No.) ;
Ray Haffner (Jane only needed a few hours to ruin his authority in his team and dismantle the team along. Haffner had to concede that Jane is smarter than him, which would never accept Red John. Haffner made a simple mistake when talking about Visualize to Lisbon, Red John wouldn't do it.) ;
Richard Haibach (Red John wouldn't be this aggressive with the cops, wouldn't let Lisbon arrest him like that without a vengeance, and wouldn't let anyone know so easily about his secret activities (photography of people without them knowing it).

(By the way, Glen Snow can't be Red John anyways because Haley, the little girl with the smiley drawn on her hand, said Red John was a white man).

That let us with ... Only 2 suspects ! Robert Kirkland and Osvaldo Ardiles !
But we know Kirkland is an obvious suspect that was introduced to make us be unaware of what happened juste next to him. I think it would be a real disappointment if, after hidding Red John so well during the show, the producers just let him appear at the end of and episode like that. He could be only a Red John complice (wouldn't be very interesting actually, but we don't know yet) OR someone that wants to find Red John ! I hope it's the second option !
Kirkland being ruled out, only one name remains ... Osvaldo Ardiles ! I can't find any proof to tell he isn't Red John actually. He has always been a calm-minded guy, doesn't let Jane overwhelm him, stays safe from all the tricks. We don't know enough of his personal life. I believe it will be really interesting.

What do you think about it guys ?

I believe that Red John is Oscar Ardiles because Oscar is in law enforcement, and has influence. Kirkland is, obviously, his accomplice, as is Bertram, and possibly Brenda. Oscar is "an old comrade" of Jane's, and they have shaken hands. He has short, straight hair, like Red John's blind lover stated.