I have to re-cite the article where the actor playing Brett Patridge actor says he is dead. There is a commenter..."Curious" who does a good job spelling out Haffner. Makes sense and I'm just trying to throw out talking points. So all credit to "Curious."

http://cliqueclack.com/p/mentalist-brett-partridge-really-dead/

I think it’s Ray Haffner because:
* He’s a polished whistler and the psychiatrist’s notes say he whistlers
* “Roy” (written by Lorelei Martin’s sister) could have been “Ray” but as she was dying she didn’t get the middle letter written correctly
* Haffner appears in every episode which has “Red” in it’s name
* He’s witty and charming like Jane, and Lorelei Martins said Jane and RJ are alike
* They shook hands before Jane learned it was someone he had already shaken hands with
* He was a member of Visualize and was there when the murders were committed in the barn
* He said he had a messed up childhood, as someone of RJ’s profile would have
* He’s left-handed and the first episode of season 6, in which RJ is polishing the linoleum knife, shows that RJ is left-handed
* His having worked in both the FBI and CBI enabled him to make connections
* He has the physical strength needed to do some of the things that RJ did