This obscure FBI unit does the domestic surveillance that no other intelligence agency can touch. This is how the NSA gets around the ban against domestic surveillance.
http://www.foreignpolicy.com/articles/2013/11/21/the_obscure_fbi_team_that_does_the_nsa_dirty_work http://www.foreignpolicy.com/articles/2013/11/21/the_obscure_fbi_team_that_does_the_nsa_dirty_work
