As a preface, I will point out that, no matter the accusations of idiots, you don't have to love Trump

to have real problems with Mueller & Co.  I think I mentioned before how he was involved in that screwed-up investigation of the anthrax attacks; I pulled that article up, doesn't this sound familiar?
Much of what authorities discovered, they leaked anonymously to journalists. The result was an unrelenting stream of inflammatory innuendo that dominated front pages and television news. Hatfill found himself trapped, the powerless central player in what Connolly describes as “a story about the two most powerful institutions in the United States, the government and the press, ganging up on an innocent man. It’s Kafka.”
...
In their own depositions, both John Ashcroft and Robert Mueller, the FBI director, said they had expressed concern to underlings about news leaks that appeared to single out and smear Hatfill. Both, however, denied any knowledge of who specifically was doing the leaking.

Throw in the mess before that mess with Whitey Bulger, and other things, and Mueller being distrusted goes back a long way.  Throw in the FBI lab scandals, and the question of "Why would they NOT record interviews with suspects?"  Which came around and bit them in the ass:
I wish that the FBI had recorded their interviews with Ms. Salman as there were several significant inconsistencies with the written summaries of her statements.
Borrowing from another piece, note the response of the agent in charge of this mess:
The FBI never recorded the alleged confession … nor any part of the 11-hour interrogation.

And that was the single biggest flaw in the case.

The feds claimed they had a smoking gun, but couldn’t prove it.

In fact, there were parts of the alleged confession contradicted by other evidence.

So when Salman declared that the federal agent who claimed she confessed was “a liar,” the feds didn’t have a single piece of concrete evidence to prove she was wrong.

And why? Why didn’t authorities record the interrogation?

“I honestly never thought about it,” testified FBI Special Agent Christopher Mayo.

Frankly, I find that incredibly odd. Apparently, so did the jury.
That he 'never thought about it' indicates a couple of things to me:
"Those people are supposed to believe what we say, not demand proof!"
and
"Screw what we were ordered to do, THIS is how we do it!"
I say "ordered to do", because
Four years ago, Attorney General Eric Holder announced that the FBI and other federal agencies would henceforth record such interviews but little has changed from the J. Edgar Hoover era.
Got that?  The Attorney General ORDERED them to record, but they didn't.  Interesting, isn't it?

So, the history of Comey and Mueller, those current heroes of the left, isn't exactly wonderful.  And "But they're going after Trump!" doesn't excuse the crap they have/are pulling.  Lord, what a mess.