They have one playbook. That playbook has "that's old, we've already discussed that to death, we have far more important current things to do than worry about some old FISA application."
Edmund Exley (Guy Pearce) told Smith about the meaning of the term 'Rollo Tomasi.' (Exley had made up the name after his legendary cop-father was shot and killed by a purse-snatcher in the line of duty.) He knew that the Police Chief was a corrupt mastermind crime boss: You're the guy who gets away with it.
No wonder the expert said "whatever that white box thing is".