At this point, the most charitable observation is that Comey values his personal reputation more highly than the reputation of the FBI. I’m prepared to be less charitable.

“This new information comes to him, and he’s afraid if he doesn’t make it public until after the election he’ll be impeached. People will say he lied to Congress. But in the end he did the self-protective thing. Was it the right thing? Put it this way: it isn’t what previous Administrations have done.” James Comey Broke with Loretta Lynch and Justice Department Tradition – The New Yorker