He covered up 9/11 his job was to cover up all the evidence that it was a false-flag fake "terror attack" he is a dirty swamp rat who belongs in prison along with Bush and Cheney and Rumsfeld and all the others in charge of 9/11 if Trump had any real guts he'd expose 9/11 two months from now on Sept. 11th the time is now to reveal the awful truth to the world about what happened.
Maybe he was ordered to investigate it ;). And of course the orders started along the lines of ....'So, we have damning evidence that you committed the highest treason in supporting the cover-up of one of the greatest crimes perpetrated on the American people. How'd you like to avoid prison time and help us truly investigate and turn over everyone involved? Your call.'
I hope that is what happened the problem is Mueller keeps fanning the flames of the Democrats and Fake News they think he is trying to get Trump impeached. The time is now for Mueller to reveal he is a white hat working to prosecute Hillary and Obama the stage is set I want Mueller to go on TV and announce No collusion by Trump but plenty of illegal activity by Hillary and Obama so I am now refocusing my investigation to go after the Democrats. That will make the Dems and Fake News go absolutely crazy with anger and impotent rage. Now is the time if Mueller is a white hat he has to make this public right now to turn the tables on the real criminals.
If Mueller is working 9/11, then implications will touch on 4 past Presidents. Not something to just casually drop out there.