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I think Red John is JJ Laroche. A lot hints to him. The name JJ Laroche may come from french laroche-la rouge, Red John. even Pruitt Taylor Vince the actor who portraits JJ is born in Baton Rouge....red again. 
He is smart,mysterious, sadistic, he has a high rank who give him access to all CBI cases, he shook hands with Jane,but they are not friends,jane hesitate to answer. And in the end Scott Sanay said red john..

After last night's episode I now think JJ is Red John. Aside from all the other clues mentioned here I think it was significant that the prisoner they interviewed said he was too afraid to upset the guy who owned the Tupperware box. Even though it's pretty creepy that JJ would cut out the guy's tongue and keep it, the prisoner seemed much too scared of the box's owner if that was all  there was to it.

if he was able to cut the tongue out of his mother`s rapist,he is capable of killing anyone,including jane`s wife and daughter

I've thought that it was Laroche for a while now.
First, his name, Laroche, always makes me think of Le Rouge, "The Red" in french. But the last chapter made it pretty clear to me when he asked Jane whether he thought of him as a friend and he didn't answer.

Laroche's Tupperware contains the tongue of the man who raped his mother but when Lisbon was interviewing him he seemed to be saying Red John...

Hi guys!
I just realized something. Lets be a bit linguistic now. His name is J. J. Laroche, it sounds a french name to me. Maybe is an artificial name, which can be the key to know his real name ( Red John).
J can stand for John, but there is two of J, so John John Laroche. Do you remember the Blake poem? Tiger, Tiger... --> J.J.
It is just a theory, but what made me write this theory is the second part of his name: Laroche, or La Roche, it sound french, so better say Le Rouge, which means " The Red", so basically his name means John, John, the Red ---> Tiger, tiger, burning bright.....
This cant be a coincidence. I hope you share my opinion. Sorry for my bad english and if anyone have already wrote this. But please comment :)