red john is Bret stiles!!
He is the most powerful person who has money and political power in this show who is also capable of manipulating people from early episodes. Gale, Reede and Thomas are Red john's buddies. you could imagine it just like three musketeers and d'artagnan.
three dot tattoos are not just coincident that means bloody promises between Red john's members. and Red John has to be very cautious man because he never risked himself to expose to Jane. Red John doesn't have to do his job because he has followers do it for him.