I agree with the posters who say Bret Stiles has some connection to Red John (Brett Partridge). I'm not necessarily sure if he they're father and son, but it is possible. Maybe Bret with one T was Red John back in the day and taught Partridge the tricks of the trade to carry on his legacy.

I was thinking about the poem Tyger Tyger the other day, and the thing that kept popping up in my mind was the question in the poem: Who "dared" create the Tyger? It is an origin story. Who was responsible for making Red John what he is? His father? Maybe. That is the central question of the poem with regards to the Tyger.

Fearful symmetry? How about Brett and Bret. Father and son? Mentor and apprentice?

Another idle thought which probably isn't relevant. Tiger spelled with a Y instead of an I(archaic English), Styles spelt with a I instead of a Y? Symmetry? 

Brett Partridge alone, doesn't seem to make full sense as Red John. He lacks the charisma, the high level connections. Brett Partridge and Bret Stiles working together would make for quite a team.