Imagine you are Huber.
Sessions announces you are his Special Investigator.
You shit a brick because you know for a fact you are not this special investigator because you are one of the people that should be investigated.
D.S. and Huber look at each other.
Sweat forms over Huber's brow. He didn't betray (((them))), but they don't know that.
D.S. knows Sessions' has a Prosecutor in pocket, and knows its NOT HUBER.
Panic Ensues.