According to me, Bret Stiles is Red John.
Following are the reasons for the same:
1. Remember Bruno Heller said : You would be disappointed to know the identity of Red John.
(Everyone is rejecting Stiles coz he's too old)
2. Lorelei Martins told Patrick Jane in Season 5 Episode 8(Red Sails in the Sunset) : "GOD, you're just like him, you know that".
(There's no one else in the list who is like Patrick Jane except Bret Stiles)
3. Bret Stiles was accused of murdering the old leader of Visualize.
(He has the motto and he killed every witness and destroyed every proof in that case)
In the latest episode Fire and Brimstone, Sheriff McAllister, Bertram and Smith have tattoos. So that means they are working for Tyger Tyger Organization and Smith has already confirmed of his side before killing Bob Kirkland. Now two suspects remains - Bret Stiles and Ray Haffner.
I don't think Ray Haffner is Red John coz he does not get fit into the character of Red John. He's acting a little crap in last few episodes.
The very first murder by Red John was done in the late 80's in the barn where there was his smiley face. It is definitely done by Stiles and now he knows Patrick is very close to him that's why he's planning something else by dying from our material world.
My money is on Bret Stiles.
Please comment if you want to say on my theory.
Thanks.
