After years of watching the show closely, i finally have him. Red John. For the pas few months i have been studying everything about Red John and the show in general.

It came to me when Jane got Lorelei out of prison.Lorelei thought it was Red John that got her out. Red John has people that can do anything for him.He has friends that can get him anywhere and out of anywhere.That got me thinking.

Dr Linus Wagner is Red John
What better cover is there, than to be in jail this whole time.You have an alibi the whole time, so no one thinks its possible. 

If you dont believe me-Rewatch the Pilot episode and the 3x8 episode named Ball of fire.Those are the 2 episodes that Linus Wagner is in. In the Pilot it is revealed that he is a psychiatrist, and he knows a ton about the human mind and has a ton of books that include Red John.

But Ball Of FIRE in the 3rd season really jumps out.Watch the whole episode, but specifically the jail scene between Wagner and Lisbon.

In that episode,Jane is taken hostage by a person from Janes past. Wagner calls lisbon up and tells her that he has info on who took him.(ONE OF RJ"S FRIENDS?)
Wagner says to Lisbon that if he tells her about Jane, he has to recieve a life sentence instead of a death penalty.He gets it,as RJ will do anything to live.

He pretty much says that he wanted to kill PJ, BUT he says " There are things so much worse than killing a man " He would rather torment and Taunt Jane like he has for the past 9 years instead of killing Jane, as death would be too easy for him.

As for getting out of Jail all of those times,His friends could easily gotten him out and back in. He probaly has people in the Prison that help him. He was most likely  the person who poisoned Rebecca in prison too. No one would think it was him, because after all he has an alibi the whole time. I promise you though,

LINUS WAGNER IS RED JOHN.