I think it's Bret Stiles because Bruno Heller probably can't pass up the idea that the main psychotic killer in the classic Stanley Kubrick film "A Clockwork Orange" was played by McDowell. To have the king of "ultra-violence" would be a pretty nice fit. 

Season 4 ep. 16 "Every man in Visualize is like a son to me"- Bret Stiles,this phrase is very important i think. I think that Brett Patridge is Stiles son, and Stiles is the real Red John, i mean "the brain", the murders however are made by Brett. There are also many litle details to my theory, such as in that episode where O'Laughlin "apears" to Van Pelt he says "Open your eyes" eyes---visualize. And if we think about it Visualize is a very powerfull cult wich has many members in the police so they have acces to any kind of information. "sometimes the easiest answer is the right answer"

However, there are some episodes wich i don't quite get, for example in the episode where Panzer is killed, PJ knew that red john will go after Panzer to kill him, it wold habe benn so easy just to follow Panzer and catch RJ...this was the episode wich made me think about the possibility that PJ is RJ...but that is another theory. 

(sorry for my English, I'm from Romania)

Okay, so I read a couple of theories about who RJ is and had just watched the clip as Patrick Jane is discussion RJ, which lead to his wife and daughters death. He tells us here that RJ is in his mid thirties. If you then take the example of the boy who killed two ppl in a barn in 1988, what was also said is that he was a boy. Probably around 12 or something, seems kinda strange that a 6 year old could kill 2 ppl. This also adds up pretty good with Patricks conclussion that he is about 30-35, at that time. If we then say that the boy was born in 1976 if you do the math, and then you will come to the conclussion that he is 36, maybe a bit older deppending on his age when he killed the first two. By this i want to say that RJ wouldn't have killed PJ's family if what he said hadn't been remotly true. Since you really dont care what ppl say if it's a lie. So that would pretty mutch rule out any one under the age of 30 and over the age of 40. Brett stiles would in this case then be ruled out and possibly many other suspects. I'm sorry that this is not an accusation against Bret, but i didn't know where else to post it.

First of all you people thinking that it is patrick jane, that is just ridiculous the show would make no sense if it was him and why would he kill his own wifr and daughter? I think it is Bret Stiles as in the episode called the red barn one of the three victims belonged to visualize and on the side of the barn there is red johns signature. Also these three people were killed roughly 25 years ago way before red john was even on the scene. The three victims are traced back to being members of Visualize and thr leader of visualize is the one and only BRET STILES.

Red John: I don't think its Bret Stiles but the cult itself, the hierachy anyway.  Here is why. Red John is methodical, seducing, patient, inspiring, eligant in a twisted sense, polite, and way off its rocker. As I describe red john, I also described the cult visualize. They are very methodical and patient. Also who can be in that many places, be so resourceful, and have that many followers? A cult. It makes more sense as a group. Finally every episode visualize finds themselve in trouble it almost seems like there more desturbed over hurting their own identity and not who ever was killed.

Bret must be red john. in the last episode we find out that one sight is connected with red jonn. A few episodes before that, laurali tells jane that she is suprised he and red john didn't become friwnds the moment they shook hands and that red john is just like jane.when you look back at the episode where we are introduced to one sight Bret asks jane "Do you know who i am" and they shake hands. When you think about it, Bret is very similar to jane in terms of personality.

With every new RJ episode, I am more and more convinced that he is not just one guy.  Used a gun/shotgun here, a linoleum knife there, poison on Rebecca (I believe he personally killed her - she wouldn't be so happy if it had been someone else walking towards her). And then you have Miranda, who was the only raped girl. I don't know anymore, the show is driving me crazy and that is why I love it. I was thinking about RJ's MO, but there isn't one. He killed girls in their homes, and killed those who insulted him. He killed Jared, fearing he would rat him out. And he killed Hicks, a CBI agent.

And here you have the second biggest mistake in the show, right behind not pressing Stiles to sing everything he knows about RJ. That second mistake is - they knew what was going to happen to Panzer, and they didn't put surveillance on him. They could've caught RJ that easily. And also, Panzer and Jacqueline insulted RJ, so he killed THEM. But when Jane spoke about RJ - he killed his family.

After Red barn, we know a little bit more. But what about the symbol ? So far we learned that RJ places it so it can be seen first, paints it with victim's blood. And now we know that the symbol was painted on the barn before Talbot and Charney were killed. Did that "kid" kill those two ? And why ? This season is seriously messing with our minds.

Right now, you can't name one suspect with him matching all the things we know about RJ. But you can see who RJ is not. And he is not :

1) Partridge -> For the love of God, people - stop thinking it's him ! His voice is similar to RJ's altered voice, not his real. They did that to throw you off, yet you are persistent it is so easy and he is RJ. Brace of Partridge ? Do you know how stupid that is ? Jane calls him out in the pilot, saying he reads Fangoria, which is a slasher magazine. RJ is to Partridge what Jordan is to Scalabrine, that's all.

2) Kirkland -> Stop mentioning that scene when Jane shakes his hand. We've all seen it, there is nothing there. It doesn't matter that Lorelei wasn't there to see that handshake. If there was something there for you believers, they didn't have enough time to become enemies since then. And we know PJ and RJ don't get along since that meeting.

3) Alex Jane -> Yes, he could've killed his daughter-in-law and his granddaughter for revenge, but that is sick. And what is his motive for the victims prior to Jane's family ? Makes no sense.

4) Danny Ruskin -> Why would he kill his sister and little niece ? And what is his motive for the earlier victims ? Also makes no sense.

5) Amos Van Pelt -> Stop writing about football conection and He is ma being Heisman. RJ will not turn out to be an organization founded by Amos Van Pelt, Notre Dame's defensive coordinator and Alabama's offensive coordinator. In the pilot, Jane tells GVP "Didn't dad always say "Life is like football. After that final whistle blows, that's the end. No more, no otherside""  And that is his only similarity with RJ.

5) Grace Van Pelt -> Oh dear God, how many idiots are there saying she had sex-change surgery and she is RJ ! Like uncle Einy said - human stupidity is infinite ! Same goes to those saying PJ is RJ.

6) Bertram - Someone who recited Blake's poem right in front of Lisbon can not be RJ. She later found that RJ recited Blake to PJ, and she could've connected those dots and tell Jane. This show will not be that lame.

7) Red sweater dude from S3 finale - he was there to make you question yourself, nothing more.

8) RJ is not Stiles, LaRoche, Ardiles, Mashburn, Haffner, Cho, Rigsby, Royston Daniel, Wagner, Molinari, Harken.

Some of the viable options left are Minelli, Mars, Cooper and we will add more once Jane gives us some big big names in the next episode.