Just nowI have simple reason to say Kirkland is not Red John Lorelei said to Jane in season5 episode8
 I only wonder why the two of you didn't become life long friends the moment you shook hands
 in previous episode Jane met Kirkland for the first time after Lorelei release ...Lorelei in the prison ,,and by the next day she escaped and spent whole day with with jane ,,how she knows that jane met Kirkland unless he informed her in the prison ,,,may be he knows RJ or he's assistance but isn't He,,,,, .....
 Kirkland said sorry mr Jane ,..jane asked him
 do u I know u,,,Kirkland answered no but I know you ,,,,and secondly in next episode last scene Jane asked Lisbon about Kirkland who's that guy !!!!