So Kirkland is now oficially dead . Since Partridge is also dead and the list now consists of 5 people , i can't imagine someone from the early seasons whom to be Red John . I guess it's Haffner , since he appears in the early episode of season 4 and it's kinda like much closer to the previous seasons . Notice that Hightower told Jane that he has been under surveillance for 9 years , and Haffner is an expert in creative surveillance techniques. This can be something ..
I'm also thinking on McAllister , but he just appears in 1 episode from all the 5 seasons , so i kinda also doubt about it )))