The fact that bruno heller has said:
RJ is in the list of 7 suspects

Let's get to the main point. When the woman in season1 finale was killed, there was a smiley face on the sky. They trace back, know that RJ solutions employed to wrote the smiley face. They found Rosalind Harker. She refuses to say to Lisbon and Jane. She goes to the other room. It makes Jane to go after her. She opened the door to make Jane saw the smiley face thought she had information about RED JOHN and then said RJ is under 6 feet and blah blah blah. She's making Jane to believe in her fake info. That's why RJ didn't kill her.

Height of the suspects
Bret Stiles                                      5' 8 and1/2"
Gale Bertram                                 6'3"
Ray Haffner                                    6'1"
Reede Smith                                 6'3"
Bob Kirkland                                 5'9"
SheriffThomas McAllister            6'
Brett Partridge                             5'11"

So, we need to do the opposite of Rosalind Harker's description.
That leaves
1.Gale Bertram
2.Ray Haffner
3.Reede Smith
4.SheriffThomas McAllister

Reede Smith is too fat to be RJ as we seen in season2 finale
Leaves
1.Gale Bertram
2.Ray Haffner
3.SheriffThomas McAllister
Let's get back to the RED RIGHT HAND episode. Before Rebecca was poisoned, she smiled. Who could make she smiled if it wasn't Red John? So how can a sheriff be in CBI?
LEAVES ONLY
1.GALE BERTRAM
2.RAY HAFFNER
When Lorelei said'I am so suspicious why didn't you guys became friends the first time you shook hands?.' That means RJ should be very close at first with Patrick. And there is another evidence. In season1 finale the handle of the cup went on the left. Means RJ likes to use his left hand. In season3 finale, the handle of the cup on Gale Bertram's desk went at right. On the contrary Ray Haffner use his left hand to pick up the phone in season4 ep.2.
IT MEANS RAYMOND HAFFNER IS RED JOHN, THE SERIAL KILLER!