I remember my briefing at Officer Basic from the JAG officer. IIRC we were told it was our duty to arrest a superior officer trying to get an illegal order obeyed. Why is this not true at the FBI?
I suspect that the reason it did not happen at the FBI is found in another part of the OIG’s report. It’s the part where it says the members of Crossfire Hurricane were all handpicked. . . and I suspect that meant from Andy McCabe down. Comey selected McCabe and McCabe selected every his lead agent who then selected every other person involved, and all had the same end goal in sight. They were of a same mind and were in agreement toward that goal. They did not arrest their superior officers because they could not see anything wrong with what they were doing, despite the illegality.
Recall what Comey named his book? “A Higher Loyalty”! There you have your answer.