Read before judging.

I have finished all The Mentalist episodes released along with, hopefully, most of you and today I just went back on the season 5 finale and I just thought to myself, Teresa Lisbon looks like a key ally to Red John. I think she may be an accomplice and an informant to Red John telling him everything that is going on. Jane may have realised certain aspects about Lisbon and possibly figured out that she may well be an accomplice to Red John.

Please, If you have seen all the episodes and had a break, Go back on the very last episode "Red John's Rules" and concentrate on Teresa Lisbon. She may very well be an accomplice of Red John.