In "red queen" Jane tests the protection around LaRoche but putting hightower, his accused and a pawn in his power play in controlling Jane through Lisbon and the CBI team. Jane then uses the entire team to lure him out by manipulating the whole team to go against all of their training and preconceptions of authority into manufacturing the death of Rigsby and Lisbon to lure Red John out proving to Red John that the team won't be blindly lead by a figure of authority and will question every untrusted lead outside their inner circle. LaRoche abdicates his position in fear of exposure.

Second, part of the theory, repitition in the references by Red John's disciples of the poem by William Blake "Tyger Tyger" (again the reference to "red queen" where LaRoche identifies the excerpt being recited by Director Wainright) and Laroche's first names or how they are referred to "J J". His surname "LaRoche" is an easy corruption of John's own name "Red" which can become"La Rouge" french for "the red", John John the red.

From his position as internal affairs unit he can oversee, hear all and see all, on all cases being handled and have access to all files on the team.

LaRoche controls the list of suspects in the Tod Johnson case.

Jane hires Culpepper to steal from LaRoche's house and Jane maniplates LaRoche with what Culpepper finds there.

LaRoche kills the gas station attendant so is capable of killing. 

If that is not convincing enough, LaRoche even looks like the cartoon Red John paints on the wall after he kills.