LETS BE REALISTIC

Red John murdered a private investigator by HIMSELF. She looks quite fit and looks like she could actually have brought up a good fight, if not win if it was someone weak. 

We have 5 suspects: 
Bret Stiles
Ray Haffner
Thomas Sheriff Mcallister
Reede Smith
Gale Bertram

I can almost guarantee Bret Stiles is not strong enough to single-handedly take down the investigator without trouble. Also, Sophie specifically said that the suspect was middle aged. Does Bret Stiles look middle aged? Very doubtful. 

This leaves us with four. The rest of these seem like they could take her down. 
Ray Haffner
Thomas Sheriff Mcallister
Reede Smith
Gale Bertram

When Reede Smith murdered Kirkland, he put 6 bullets into him, but shot seven. What does this mean? When the report came out, it said that he had 6 bullets into him. Now that usually means to the viewers that, "Oh, Reede Smith might be Red John because he shot 6 times." But he wasn't trying to shoot 6. He shot seven times. 

Also, it seems awfully careless of Smith to have shot a man six times just because he "tried to escape." Why not shoot 1 in the head? He doesn't seem like he has the methodical thought put into things like Red John might. Its unlikely its Smith, and he hasn't been in the show very much at all. 

Three suspects: 
Ray Haffner
Thomas Sheriff McAllister
Gale Bertram

Between these three I can't be completely sure. When Red John visited Sophie, he said that he had a fear of heights, but there is NO REASON for Red John to expose this to Sophie. It is much too risky. However, the whistling part may not have been intentional by Red John. We know that McAllister has a fear of heights, and doesn't like pigeons at all. Interesting? Yes.

Ray Haffner is probably the most likely suspect for all viewers. He likes Lisbon, (there is a theory that Red John likes Lisbon) he was coincidentally gone right when the investigator was murdered. He's fit, charming, and has a Visualize Connection. The private investigator said that she was hired by Visualize. 

This makes Haffner a prime suspect, as almost all arrows point at him. But it seems too obvious. If Haffner was Red John, everybody could see it coming, including most passerby viewers. I feel like there is something larger cooking up. 

And lastly, Gale Bertram. It would be very ironic if it were him, as he is, after all, Jane's boss. We don't know much about Bertram, besides his personality. He evidently doesn't like losing very much. But we don't know if this is a fake personality. 

We don't know who else has a Visualize connection, or else it would be Haffner, but that would be too obvious. So i'll go out on a limb and say that its
Gale Bertram
How fun.